&EPA
United States
Environmental Protection
Agency
Environmental Accounting
Using Emergy: Evaluation
of Minnesota
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EPA/600/R-09/002
January 2009
Environmental Accounting Using Emergy;
Evaluation of Minnesota
By
Daniel E. Campbell
USEPA, Office of Research and Development
National Health and Environmental Effects Research Laboratory
Atlantic Ecology Division, Narragansett, RI 02882
Andrew Ohrt
ArcadisU.S., Inc.
2300 Eastlake Avenue East, Suite 200
Seattle, Washington 98102
US Environmental Protection Agency
Office of Research and Development
National Health and Environmental Effects Research Laboratory
Atlantic Ecology Division
Narragansett, RI 02882
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Environmental Accounting Using Emergy: Minnesota
NOTICE
This report is contribution number AED-08-006 of the Atlantic Ecology Division (AED), National Health and
Environmental Effects Research Laboratory (NHEERL), Office of Research and Development (ORD). The research
described here has been funded wholly (or in part) by the U.S. Environmental Protection Agency and the document
has been subjected to the USEPA's peer review process and has been approved for publication. However, we note
that the opinions expressed in this report are those of the authors and they are not necessarily those of the U.S.
Environmental Protection Agency. In addition, the methodology used in this report is not completely developed and
the approach itself is not accepted by everyone in the scientific community. Therefore, caution should be employed
in using the data and conclusions provided here. The data, calculations and conclusions reported herein have not been
subjected to formal analyses of their uncertainties, and therefore should be viewed with extreme caution; no claims to
their accuracy and veracity can be made at this time. Technical issues preventing the complete application of these
methods include better methods to document far-field environmental liabilities such as disturbance to natural carbon,
nitrogen, and sulfur budgets of regions. Finally, the mention of trade names or commercial products does not
constitute endorsement or a recommendation for use.
ABSTRACT
Often questions related to environmental policy are difficult to resolve successfully, because robust solutions
depend on accurately balancing the needs of both human and natural systems. To accomplish this end the
socioeconomic and environmental effects of policies must be expressed in common terms so that both the
contributions of the environment and the contributions of the economy to human well-being are valued fairly.
Emergy is an accounting quantity that has the property of expressing all forms of energy in terms of their equivalent
ability to do work when used in the system of which they are a part. Based on past studies and a previous report in
this series, environmental accounting using emergy has proved to be a method that can be used to objectively value
the work of the environment, economy and society by using an energy-based unit, the solar emjoule (sej) and a
combined emergy-monetary unit the emdollar (Em$). Emergy tabulates the available energy of one kind required for
the production of a product or service i.e., the solar joules used up both directly and indirectly in the past to make the
product or service. The unit of emergy is the emjoule, which denotes that the energy has been used in the past in
contrast to a joule of available energy that is an energy potential that can be used in the present. What something can
do when used within its network is represented by its emergy and not its energy. Thus, energy alone is not a
sufficient basis for making policy decisions.
This USEPA Project Report contains an emergy evaluation of the State of Minnesota and it includes a guide to the
Emergy Analysis methods used to characterize a state within the larger context of its region and nation. A summary
of the results of this analysis based on the values of emergy indices calculated for the State and their interpretation
follows: (1) Twenty-one percent of the emergy used in the State in 1997 was derived from home sources, which
indicates a moderate potential for self-sufficiency. (2) The emergy use per person was 1.53E+17 sej/person. This
index showed that Minnesotans have a high overall standard of living compared to the national average. (3) The
import/export emergy ratio showed 1.33 times as much emergy leaving the State in exports as is received in imports,
which indicates a slight imbalance in the exchange of real wealth with the Nation. However, when iron ore (taconite)
is removed from the import-export balance, the emergy of exports is only 10% larger than that of the imports. (4) The
emergy used per square meter (3.23E+12 sej/m2) indicates that an average location in the State is developed relative
to an average place in the Nation. (5) The emergy to dollar ratio was 4.66 E+12 sej/$, thus the purchasing power of a
dollar in Minnesota in 1997 was 1.82 times that of an average place in the United States. This ratio had fallen to 1.69
times the national purchasing power of a dollar by 2000. (6) The investment ratio was 3.81:1, which indicates a
relatively low intensity of matching between purchased economic emergy invested from outside the State and the
emergy of renewable and nonrenewable environmental resources within the State. This index suggests that
Minnesota is still an attractive place for further economic investment. (7) The environmental loading ratio was
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Environmental Accounting Using Emergy: Minnesota
37.1:1, indicating a more intense matching of purchased inputs with renewable energy from the environment than
was found for West Virginia (20.4:1) or the Nation as a whole (19.6:1). Higher environmental loading ratios
potentially result in higher stress on ecosystems and a heavier "load" on the waste processing capacity of the
environment. (8) Minnesota can support 2.6% of the present population at the 1997 standard of living using its
renewable resources alone in their current state of development compared to 3.0% for West Virginia and 4.9% for the
Nation.
Minnesota is a state with large regional differences. The Northeastern region appears to be a hinterland exporting
vast quantities of emergy in its natural resources. For example, the iron mining sector has a balanced monetary
exchange but the emergy exchange shows a 42:1 advantage in favor of the buyer. The agricultural and industrial
regions in the remainder of the State export value added products that command a premium over the average skill
level used to produce the products imported. This premium paid for the services of Minnesota workers is the main
reason for the State's high standard of living relative to other states. Minnesota's pool of highly educated and skilled
labor can be attributed to an early and continuing interest in and support for education in the State. Based on this
evidence the best thing that the State can do to ensure a prosperous future is to continue to educate forward-thinking,
highly-skilled individuals through further developing and maintaining its school systems.
Keywords: emergy analysis, environmental accounting, Minnesota, renewable resources, nonrenewable resources,
sustainability, quality of life, import-export balance
ACKNOWLEDGMENTS
We are most grateful to the U.S. Forest Service North Central Research Station and to Pam Jakes of that
institution for hosting University of Minnesota graduate student, Andrew Ohrt during the time required to complete
this research. Dr. Jakes participated in research planning and supported the research activities reported here. The
North Central Research Station and Dr. Jakes provided all logistical support needed by Mr. Ohrt during his stay
there. In addition, David Bengston provided assistance and consultation on forest resources, as well as on the
availability of data. The Mid-Continent Ecology Division (MED) of the National Health and Environmental Effects
Research Laboratory (NHEERL), Office of Research and Development, USEPA provided a venue for discussion of
this work, insights on the State and half of the funds for its publication. Denis White of the Western Ecology
Division (WED) of the National Health and Environmental Effects Research Laboratory (NHEERL) performed the
analysis of the emergy stored in soils. This manuscript was reviewed by Philip Cook of MED, Naomi Detenbeck of
AED, and Oilman Veith of the Natural Resources Research Institute, University of Minnesota-Duluth.
in
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Environmental Accounting Using Emergy: Minnesota
Preface
PURPOSE OF THE REPORT
This USEPA Project Report has several purposes.
The first purpose is to provide a second peer-reviewed
report on a state for comparison with the results of our
original report on West Virginia. The Minnesota and
West Virginia reports are two analyses in a
comparative analysis of eight states that were
evaluated for the years 1997 and 2000. In addition,
this report serves as a further guide to Emergy
Analysis with particular emphasis on those methods
used to characterize a state within the United States
and the data needs for performing emergy analyses on
all scales, including an expanded section on
transformities with many new calculations. This report
also provides emergy indices for the State of
Minnesota that are needed to perform a proposed
regional analysis of sustainability of the Arrowhead
Region of Northern Minnesota. In this report we
applied the results of our study to gain an energy
systems perspective on some current policy questions
facing the people of Minnesota.
SIGNIFICANCE OF THE REPORT
Many people struggle to understand the concept of
emergy and why we go to so much trouble to
document economic and ecological flows and storages
in these terms. The practical answer is that the
accounts for environmental systems cannot be kept in
dollars alone, because environmental systems are
based on both the work of humanity, which is paid for
by a counter flow of dollars, and the work of
ecosystems, for which no money is paid. An accurate
picture of environmental systems requires that we
account for the flows and storages of energy, matter,
and information that are responsible for supporting
economic and social activities and that may not be
accompanied by flows of money. Energy can be used
as a common denominator for quantifying all these
flows. Converting flows of energy to emergy puts the
work done by the economy and the environment on
the same basis, so that economic and environmental
flows are directly comparable. While it is true that
dollar values are directly comparable, it is also true
that economic markets only value a subset of the
products and processes that are important in
environmental systems. The key synthesis produced
by Emergy Analysis is an accounting of social,
economic and environmental flows in common terms
on an objective basis. Thus, for the first time, what is
removed from Minnesota is shown in true relationship
to what is received in return. For example, it is true
that everyone in Minnesota realizes that farming,
mining, manufacturing, and timber are important
sectors in the economy, but this is the first time the
numbers have been calculated to show the relationship
of the real wealth (emergy) in natural and human
capital that supports the flows of emergy and the
counter current of money moving through these
sectors annually. The exchange of real wealth between
Minnesota and the Nation is quantified for the first
time and contrasted with those of another resource
rich state, West Virginia. The importance of
recognizing the true nature of value in exchanges is
easily illustrated by the inequitable barter between
Europeans and Native Americans in which ecological
resources, e.g., animal skins and land of great value,
were exchanged for relatively less valuable items of
industrial society. Emergy accounting can potentially
give environmental managers tools similar to those
regularly used by financial analysts to make business
decisions. However, we are far from this point at
present and there is much work left to be done by
those who thoughtfully read this report. Further
development of the emergy analysis methods and
tools presented in this report and closer coordination
with existing methods of environmental impact
assessment, e.g., life cycle assessment, will make it
possible for managers to first examine complete and
commensurate economic and environmental
accounting data before making policy decisions about
environmental systems.
The State of Minnesota and its relationships with
its region and the Nation are characterized in the case
study presented in this report. Insights from this study
may be useful in establishing a context for
determining policies for the State as a whole, but finer
scale analyses must be performed to address more
specific environmental management problems, such as
what is sustainable for a region within the State. In
addition, the analysis methods described here can be
used as a guide to creating emergy accounts for any
state in the United States.
IV
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Environmental Accounting Using Emergy: Minnesota
STRUCTURE OF THE REPORT
This technical report gives an overview of the
emergy accounting and analysis methodology, which
can be used to evaluate environmental systems on any
scale of organization (Odum 1996). However, it is
impossible to condense the methods and insights of a
comprehensive methodology in a single, relatively
short document. For this reason, Section 2 (Methods)
of this paper focuses on methods, calculations and
data sources needed to evaluate a state within the
United States of America. Even with this restriction,
the task is daunting because there are 50 states and
each one will present the researcher with new
problems to solve. So far we have begun work on 10
of the 50 states, and as expected, almost without
exception each one has presented a new theoretical or
technical challenge. In Campbell etal. (2005) we
made the task somewhat easier through the
development of a method for determining the imports
to and exports from any state using readily available
data from the U.S. Census Bureau's Commodity Flow
Survey that is performed every 5 years, most recently
in 1997, 2002, and 2007. Application of the emergy
analysis method is demonstrated through reporting a
case study of the State of Minnesota (Section 3),
which is presented in lieu of a Results section. This
section of the report is written so that it can stand
alone as a final report on the Emergy Analysis of
Minnesota. Those readers who are primarily interested
in the results of this study can go directly to Section 3.
The emergy analysis and environmental accounts
for the State of Minnesota given in the case study
include the following eight elements that we used to
characterize any state: (1) a narrative history, (2) a
detailed energy systems diagram of the state as an
environmental system with supporting tables, (3) the
Emergy Income Statement showing annual emergy
and dollar flows of renewable and nonrenewable
resources, production, consumption, imports and
exports, (4) the Emergy Balance Sheet showing some
of the stored assets in the state, (5) an aggregate
diagram giving a macroscopic overview of the energy
resource base for the state's economy and a summary
table from which indices were calculated, (6) emergy
indices of system structure and function, (7) the
emergy signature for the state, and (8) the examination
of several issues of concern for the well-being of
Minnesota and its people in the future.
Following the Emergy Analysis of Minnesota,
there is a Discussion (Section 4) which examines (1)
some unique problems in the analysis of Minnesota
and the solutions employed, (2) quality assurance, the
reliability of the data, and areas of uncertainty in the
analysis, and (3) the use of emergy accounting data
for environmental decision-making and planning for
the future. References are given in Section 5 and the
data sources used along with their Worldwide Web
addresses can be found in Section 6. Extensive data
and documentation to support the method and the case
study are given in the appendices found in Section 7.
These appendices are as follows: the Energy Systems
Language (Appendix A), information on the
transformities used in this report (Appendix B), notes
documenting the energy and emergy calculations
(Appendix C), import-export calculation methods
(Appendix D), and emergy analysis tables for
Minnesota in 2000 (Appendix E). Supplemental
information on this analysis and errata are posted at
http://www.epa.gov/aed/research/desupp5.html.
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Environmental Accounting Using Emergy: Minnesota
TABLE OF CONTENTS
Notice ii
Abstract ii
Acknowledgments iii
Preface iv
Purpose of the Report iv
Significance of the Report iv
Structure of the Report v
Section 1
Introduction 1
Section 2
Methods 3
2.1 Understanding the System 3
2.2 Overview of Emergy Analysis Methods 3
2.2.1 Diagramming and Models 3
2.2.1.1 The Energy Systems Language 4
2.2.1.2 Simulation Models 5
2.2.2 Emergy Tables 6
2.2.3 Data Sources and Model Evaluation 6
2.2.4 Transformities 7
2.2.5 Flow Summary and the Calculation of Indices 8
2.3 Creating the Emergy Income Statement 8
2.3.1. Evaluating Renewable Resources 8
2.3.2. EvaluatingNonrenewable Resources 9
2.3.3 Evaluating Exports and Imports 9
2.3.3.1 Determining the Emergy in Materials 10
2.3.3.2 Determining the Emergy in Services 11
2.4 Creating the Emergy Balance Sheet 12
2.5 Constructing the Emergy-Economic Overview 13
2.5.1 Summary Emergy and Dollar Flows 13
2.5.2 Determining the Renewable Emergy Base for a System 13
2.6 Emergy Indices 14
2.6.1 The Emergy/Money Ratio 15
2.6.2 The Emergy Exchange Ratio 15
2.6.3 The Investment Ratio 15
2.6.4 The Environmental Loading Ratio 15
2.6.5 Indices of Self-Sufficiency and Dependence 156
2.6.6 Indices of Sustainable Use 16
2.6.7 Indices of Quality of Life 16
2.7 Energy and Emergy Signatures 16
Section 3
An Emergy Evaluation of Minnesota 17
VI
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Table of Contents
3.1 Introduction 17
3.2 The Efficacy of Emergy Accounting in Answering Management Questions 18
3.3 Narrative History of the Land, People and Natural Resources of Minnesota 18
3.3.1 Timber 23
3.3.2 Flour 23
3.3.3 Surface Water 23
3.3.4 Iron Ore 23
3.3.5 Taconite 24
3.3.6 Other Minerals 24
3.3.7 Peat 24
3.3.8 Agriculture 24
3.3.9 Education 24
3.4 An Energy Systems Model of Minnesota 25
3.5 The Emergy Income Statement for Minnesota 32
3.6 The Emergy Balance Sheet for Minnesota 34
3.7 Overview Models and Flow Summary 38
3.8 Emergy Indices 40
3.9 The Emergy Signature for the State 41
3.10 Analysis of Minnesota and Comparison with other States 41
3.10.1 Characteristics of Minnesota Based on Emergy Analysis 43
3.10.2 Comparison with other States 46
3.11 Summary of Findings as Related to the Management Questions 50
3.12 Recommendations to Managers 53
3.13 Minnesota and the Future 53
Section 4
Discussion 54
4.1 Standard Methods versus Intellectual Creativity 54
4.2 Methods Developed and Refined in this Study 55
4.3 Quality Assurance: Reliability of the Data and Uncertainty 55
4.4 Future Research and Reports 58
Section 5
References 59
Section 6
Data Sources 644
Section 7
Appendix APrimary Symbols of the Energy Systems Language 68
Appendix B Sources, Adjustments, and Calculation of Transformities 70
Bl. Information Sources for the Emergy per Unit Values 71
B2. Estimation of Transformities for the SCTG Commodity Classes 72
B3. Calculation of New or Revised Transformities 74
Appendix C Calculation of Energy and Economic Values 100
Cl Notes for Table 4 Renewable 101
C2 Notes for Table 5 Nonrenewable Ill
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Environmental Accounting Using Emergy: Minnesota
C4. Notes for Table 7 Exports 118
C5. Notes for Table 8 Storaged Assets 120
C6. Notes for Table 9 Summary Flows 123
C7. Notes for Table 10 Calculation of Emergy Indices 124
Appendix D Calculating the Import and Export of Materials 126
Dl. Creating Export/Import Spreadsheets for Materials 127
Appendix E Minnesota Emergy Accounts for 2000 134
FIGURES
Figure 1. A detailed energy systems model of Minnesota 26
Figure 2. Aggregated diagram of Minnesota's economy and emergy resource base 38
Figure 3. Summary of Minnesota's environmental and economic emergy flows 40
Figure 4. The emergy signature of the State of Minnesota in 1997 42
Figure Al Primary symbols of the Emergy Systems Language 69
LIST OF TABLES
Table 1. Tabular format for an Emergy Evaluation 6
Table 2. Definition of pathway flows for the systems model of Minnesota's environment 27
Table 3. Definitions of the components for the systems model of Minnesota's environment 31
Table 4. Annual renewable resources and production for Minnesota in 1997 35
Table 5. Annual production and use of nonrenewable resources in 1997 36
Table 6. Annual imports to the Minnesota economy in 1997 36
Table 7. Annual exports from the Minnesota economy in 1997 37
TableS. Assets of Minnesota in 1997 37
Table 9. Summary of flows for Minnesota in 1997 39
Table 10. Minnesota emergy indicators and indices for 1997 42
Table 11. Analysis of Federal outlay and tax relationships 45
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Table of Contents
Table 12. Comparison of emergy flows and indices for Minnesota 47
Table B 1.1 The values and sources for transformities and specific emergies used in this report 71
Table B2.1 Transformities and specific emergies for the SCTG commodity classes 72
Table B3.1 Transformity of snow 74
Table B4.1 The factors needed to convert one planetary baseline to another 99
Table B4.2 Emergy to Money Ratio of the United States for 1997 and 2000 99
Table Cl.l Data used to determine the geopotential energy of rainfall 104
Table C2.1 Detailed account of the emergy imported in material inflows 115
Table C2.2 Export and import of services between Minnesota and the Nation 116
Table C2.3 Determination of imported and exported services 117
Table C3.1 Emergy in the materials exported from Minnesota 118
Table C4.1 Services in imported fuels and minerals 123
Table C4.2 Services in exported minerals 124
Table Dl Approximate conversion for SCTG, SIC and NAICS industry classification codes 128
Table D2 Calculation of Minnesota exports from the state to state commodity shipments 129
Table D3 Our original example of estimating missing import data from Alabama to West Virginia. ..132
Table El Annual renewable resources and production in 2000 135
Table E2 Annual production and use of nonrenewable resources in 2000 136
Table E3 Annual imports to the Minnesota economy in 2000 136
Table E4 Annual exports from the Minnesota economy in 2000 137
Table E5 Assets of Minnesota in 2000 137
Table E6 Summary of flows for Minnesota in 2000 138
Table E7 Minnesota emergy indicators and indices for 2000 139
IX
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Environmental Accounting Using Emergy: Minnesota
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Section 1
Introduction
Introduction
Accurate accounting of the inflows, outflows and
storages of energy, materials, and information is
necessary to understand and manage environmental
systems at all levels of hierarchical organization. The
accounting tools, i.e., the emergy income statement,
emergy balance sheet, and emergy indices described in
this document can be used to analyze and understand
systems defined for any arbitrary set of boundaries.
Boundaries of concern to us define an environmental
system containing both ecological and socioeconomic
components. The research or management questions
asked at each level of organization will be somewhat
different but the most important questions that are
concerned with the overall condition of the system will
be illuminated by information and indices related to the
system's inflows, outflows and to the storages of
energy, matter, and information in the system. In this
report we present the methods of environmental
accounting using emergy and apply them to analyze the
State of Minnesota. Therefore, the particular sources of
data and methods presented here will relate to the
calculation of the important flows and storages for states
within the United States.
At present, records for the environment are kept in
terms of physical units such as pounds of chemical
pollutants discharged, miles of degraded streams, or the
number of endangered species present in a given area,
while the accounts of human activities are for the most
part kept in dollars. Neither accounting mechanism is
able to address the credits and debits of the other, thus
there is often a gap in the scientific assessment
information given to managers faced with solving
complex environmental problems that have social,
economic and ecological consequences. To keep
accurate accounts for the environment, the economy,
and for society we need a system capable of expressing
the debits and credits (costs and benefits) that accrue to
each in common terms. For more than 100 years,
physical and social scientists have struggled with this
problem, i.e., how to incorporate resource limitations
and contributions into the formulations of economics
(Martinez-Alier, 1987). Land, labor, energy and other
physical quantities have been tried without much
success. Often these efforts centered on available
energy, i.e., energy with the potential to do work, as a
potentially unifying common denominator for
accounting purposes, because it is both required for all
production processes and incorporated in all products of
production. These early efforts failed largely because
none of the proposed energy-based accounting methods
considered differences in the ability to do work among
energies of different kinds (Odum 1996).
In the 1980s, H.T. Odum and his colleagues solved
this problem through the development of the concepts of
emergy and transformity (Odum 1986, 1988, Science-
man 1987). Emergy is the available energy of one kind
previously used up directly and indirectly to make a
product or service. The unit of emergy is the emjoule,
which connotes the past use of energy that was required
to create the present product or service. Transformity is
the emergy required to make a unit of available energy
of the product or service. Most often, emergy accounts
for the environment and the economy are kept using the
solar joule as a base unit. In this case solar
transformities are expressed as solar emjoules (sej) per
joule (I). Empower is the flow of emergy (sej) per unit
time. Emergy is related to the system of economic value
through the emergy to money ratio. The emdollar (Em$)
value of a flow or storage is its emergy divided by the
emergy to money ratio for an economy in that year
(Odum 1996). Odum's innovative definition of emergy
established a medium for environmental accounting that
for the first time made it possible to express economic
commodities, services, and environmental work of all
kinds on a common basis as solar emjoules. In this
report we use the methods of emergy accounting to
demonstrate how keeping the books on environmental
systems can help us identify problems and seek
solutions at the macroscopic level of a state economy.
In our previous study of West Virginia (Campbell et al.
2005a); we began to adapt two standard accounting
tools, the income statement and the balance sheet for use
with emergy. Respectively, these tools allowed us to
characterize state annual activities and long-term assets.
We propose that creating combined emergy and
monetary accounts for environmental, economic, and
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Environmental Accounting Using Emergy: Minnesota
social systems is a method that will allow us to bridge
the gap between economic and ecological analyses of
natural capital and processes in a plausible and
integrated manner, thereby leading to more accurate and
comprehensive evaluations of the effects of
environmental policies.
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Section 2
Methods
Methods
Emergy evaluations of the macroscopic features of
an environmental system such as a state, region, or
nation are carried out in the same manner for each
system regardless of its size or level in the hierarchy of
organization, e.g., county, state, nation, 1st, 2nd, ... 6th
order watersheds, etc. Emergy analyses like other
assessment methods are guided by research or
management questions. In general, the hierarchical
organization of ecological and economic systems
requires that emergy accounts be created for more than
one level of organization to obtain accurate answers to
questions about a system at any particular level of
organization. Multiple levels of organization are
examined because large-scale patterns within a system
are often determined by energy inflows from the next
larger system, whereas, internal system dynamics may
be affected by policy changes in the management of
important subsystems. The examination of multiple
levels of organization is also recommended because
environmental policies often have different
consequences at different levels of system organization
(Odum and Arding 1991). The general rule is that
analyses at three levels of organization (the system, its
subsystems, and the next larger system) are the
minimum required for a thorough understanding of a
particular system. Because of time and labor constraints
the emergy analysis presented in this report varies from
this standard because (1) it does not include an
examination of important subsystems within the state,
e.g., the rapidly growing corn ethanol industry, and (2)
international trade between the United States and
Canada is not explicitly considered; therefore, it is only
the first step in a complete emergy analysis of the state.
2.1 Understanding the System
Effective models and analyses depend on the degree
to which the investigators understand the system that
they have chosen to analyze. For this reason, a thorough
study of the system to be analyzed and its relationship to
the next larger system, which determines long-term
trends, is a prerequisite for successful analysis. Before
performing emergy analyses of states or other systems,
we recommend that investigators review existing studies
containing current and historic information on the state
with a view toward characterizing it as an environmental
system. Environmental systems include the economic
and social infrastructure and activities of humanity as
well as the storages, flows and processes of ecosystems.
In the method presented here and illustrated in the
Results section, the knowledge gained through this
review is captured in the narrative history of the state.
The narrative history is a vehicle for understanding how
renewable and nonrenewable resources have shaped the
current economy in the state. Setting down the history of
the state helps trace causal pathways from the past to the
present and establishes the historical context of
changing relationships between the state and the nation.
The knowledge gained through this review serves as a
basis for creating a detailed energy systems diagram of
the state as discussed below.
2.2 Overview of Emergy Analysis Methods
There are five main steps required to complete an
emergy evaluation. First, a detailed systems diagram is
completed. The second step is to translate this
knowledge into an aggregated diagram of the system
addressing specific questions. Third, descriptions of the
pathways in the aggregated diagram are transferred to
emergy analysis tables where the calculations needed to
quantitatively evaluate these pathways are compiled.
The fourth step in the method is to gather the raw data
needed to complete the emergy analysis tables along
with the conversion factors (energy contents,
transformities, etc) needed to change the raw data into
emergy units. Finally, after the raw data has been
converted into emergy units, indices are defined using
an aggregate diagram (Odum 1996, Lu etal. 2007) and
calculated using the appropriate data. These five steps
are discussed in more detail in the following sections.
2.2.1 Diagramming and Models
First, a detailed energy system diagram is
constructed representing all interactions between human
and natural components of the system that have been
identified as relevant (Fig. 1). The Energy Systems
Language symbols and their intrinsic mathematics (see
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Environmental Accounting Using Emergy: Minnesota
Appendix A, Fig Al and Odum 1994) are used to
develop models of ecological and socio-economic
interactions and components representative of the
functions and structures within the system or process of
interest. In an energy systems diagram, structure
encompasses the system components and their
arrangement, and function includes pathways of energy
flow and interactions. Components can be both physical
entities and properties such as information or aesthetics
that are usually considered as intangible, but require
small energies for their storage and operation. The
pathways and interactions can be both physical flows
such as electricity or raw materials as well as control
mechanisms, e.g., logic programs controlling animal
migrations or management decisions.
It is important to include all known connections
between system components in the draft diagram to
ensure completeness of the evaluation. A diagram like
this is a useful tool for defining data needs. Once the
exercise of defining all known interactions that affect
the system components is completed, there is usually
enough information to construct working hypotheses
about the mathematical expressions that govern these
processes. This in turn points to the appropriate factors
that need to be measured when field work is required.
Variables in the detailed model are then aggregated,
according to similarity of function, into variables
considered important in controlling the system behavior
that is relevant to specific research or management
questions. Preliminary evaluations of the emergy in
system storages and flows helps in determining the
dominant components and processes of the system that
should be included in the aggregate diagram.
Aggregating does not mean removing any component
from the system. It refers to combining components and
using either averaged data or data from the dominant
entity to evaluate the component or process. For
example, data on a biological component can be
weighted for population percentages. The goal of
aggregation is to obtain the simplest possible system
that still allows the original research or management
question to be answered.
Committing our understanding of the energy and
material flows, storages and connections within an
ecosystem to paper invites review of the completeness
and accuracy of the conceptual thinking. It is not
necessary to include all known details in a diagram. In
the emergy accounting procedure presented in this
document, the pathways of primary interest are those
crossing the boundaries, both as inputs and as outputs.
At this scale, the focus is on the external flows
supporting the environmental system. The only internal
interactions of interest are the extractions of natural
resource storages for economic use, e.g., minerals or soil
erosion. Other internal pathways are drawn, but much of
the detail concerning the workings of each component
can be omitted.
2.2.1.1 The Energy Systems Language
The tools and methods for constructing an energy
systems diagram are discussed extensively in Ecological
and General Systems (Odum, 1994). The Energy
Systems Language is a visual mathematics because each
symbol is mathematically defined. A network of these
symbols translates directly into a set of simultaneous 1st
order differential equations. Energy Systems diagrams
represent both kinetics and energetics in a single
diagram and they demonstrate and obey the 1st and 2nd
laws of thermodynamics in their structure (Odum 1994).
The commonly used symbols and conventions of the
language are briefly described below to assist the reader
in understanding the energy systems diagrams used in
this document (Figure Al).
System boundary A rectangular box represents the
system boundaries. This is an arbitrary decision and
boundaries are often chosen to address an issue or
question being evaluated. Determining the boundary
requires specifying the spatial and temporal scale of the
analysis.
Forcing functions Any input that crosses the
boundary is an energy source for the system. Such
inflows include energy flows, materials, information,
genes of living organisms, services, as well as inputs
that are destructive, such as wastes and toxicants.
External inputs are represented with a circular symbol
and are arranged around the outside border from left to
right in order of increasing transformity with sunlight on
the left and information and human services on the right.
Pathway lines Flows are represented by lines and
include energy, materials, and information. Money is
shown with dashed lines and always flows in the
opposite direction to the material or energy flow with
which it is coupled. Lines without arrowheads flow in
proportion to the difference between two forces and
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Methods
represent a reversible flow that follows the
concentration gradients.
Outflows Any outflow that still has available energy,
e.g., materials more concentrated than the environment
or usable information, is shown as a pathway exiting
from any of the three upper system borders, but not from
the lower border. Degraded or dispersed energy, with
insufficient ability to do work in the system, is shown
with gray lines leaving at the bottom of the diagram
through a single arrow going to the heat sink.
Adding pathways Pathways add their flows when
they join and when they enter the same storage. Every
flow in or out of a storage must be of the same type and
is measured in the same units.
State variables Storages of material, energy and
information are shown as tanks, which may occur alone
or within system compartments. Changes in the system
can be recorded as fluctuating accumulations within
each tank. In system diagrams using group symbols, the
actual simulation details, such as tanks and complex
interactions flowing into and out of each tank, are not
presented. However, a state variable is always implied
for every compartment within the diagram whether it is
shown or not.
Intersection/interaction Two or more flows that are
different, but required for a process, are drawn entering
an intersection symbol. The flows to an intersection are
connected from left to right in order of their
transformity, the lowest quality one connecting to the
notched left margin and the higher quality flows
connecting to the top of the interaction symbol.
Photosynthesis is an example of a multiplicative
interaction in which light, plant biomass, and nutrients
are the inputs required to produce organic matter.
However, any mathematical relationship can be used to
define an interaction by making the appropriate symbol
or notation on the interaction symbol. A flow of one
entity cannot go from its tank to a tank with a different
entity without passing through some interaction, e.g.,
sunlight cannot flow into a tank containing
phytoplankton carbon without first interacting with
nutrients, phytoplankton biomass and other inputs to
produce a flow of carbon in gross primary production. If
hierarchical symbols are being used, e.g., the producer,
consumer or a rectangular box for a sub-system (Figure
Al), disparate flows can enter the symbol without
showing the interactions. However, the interactions are
implied and are shown explicitly when the hierarchical
symbol is completely specified (Odum and Odum
2000).
Counter-clockwise feedbacks High-quality outputs
from consumers, such as information, controls, and
scarce materials, are fed back from right to left in the
diagram. Feedback from right to left also represents
recycle or a loss of concentration, because of
divergence, with the service usually being spread out to
a larger area. Feedback control or recycle paths go from
right to left over the top of all other components and
pathways.
Sensor If the quantity of a component in some way
affects a flow without using up the component, a small
box (sensor) is placed at the top of the storage tank and
information on the stored quantity is drawn from this
point for use by another symbol, e.g. an interaction or
logic program. For example, the emergy stored in the
biodiversity of a National Park may attract tourists to
visit the park, but it is not ordinarily diminished as a
consequence.
Material balances Since all inflowing materials
accumulate in system storages or flow out, each
inflowing material such as water or money needs to
have a budget determined.
2.2.1.2 Simulation Models
The characterizations of Minnesota given in this
report are based on data from 1997 and 2000 and as
such they are snapshots of a dynamically changing
system. The dynamic system processes of the State are
constantly changing under the influence of both external
forcing functions, e.g., climate change, fuel availability,
etc., as well as variations in the internal structure of the
system, e.g., the growth and development of alternative
energy industries such as wind power and ethanol.
Microcomputer simulation is the standard Energy
Systems Analysis tool used to examine system
dynamics. Simulation models are not used in this report,
but they will be important in future studies of the
sustainability of the State and its regions and in
predicting the development and behavior of important
subsystems such as the ethanol industry within the State.
Simulation models are often helpful in considering
alternative futures, investigating dynamic properties,
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Environmental Accounting Using Emergy: Minnesota
Table 1. Tabular Format for an Emergy Evaluation
Col. 1 Column 2 Col. 3 Column 4
Column 5
Column 6
Note
Item
Data
J,g,$
Solar Emergy /Unit
sej/J, sej/g, sej/$
Solar Emergy
sej, sej/y
Em$
U.S. Em$
and making predictions. They act as a controlled
experiment and allow the investigator to adjust one
variable at a time and note the resulting changes to the
system. In creating a simulation model, an evaluated
diagram showing the initial conditions for all state
variables and pathway flows is made. Storages and
flows are determined from the literature or from field
measurements of biomass, production rates, etc. The
simulation model is translated into a set of simultaneous
first order differential equations containing the
mathematical functions governing rates and interactions
that result in changes in the state variables under a given
set of forcing functions. These differential equations are
written as difference equations in a programming
language and solved on the computer to predict the
changes in each state variable as a function of time or
space. More detail on the use of models and simulation
in energy systems analysis can be found in Odum and
Odum (2000).
2.2.2 Emergy Tables
Emergy analysis tables provide a template for the
calculation of the emergy values for energy storages and
flows. In the emergy tables, raw data on the mass of
flows and storage reserves are converted to energy and
then to emergy units and emdollars to aid in
comparisons and to provide information for public
policy decision-making. Emergy tables are used to
create the accounts for the emergy income statement and
emergy balance sheet.
The common format used to set up emergy tables is
illustrated above. Each emergy evaluation table has six
columns as shown in Table l.The columns are defined
as follows: Column 1: Note. The line number for the
item evaluated is listed. Each line number corresponds
to a footnote where raw data sources are cited and
calculations shown. The footnotes referenced in this
paper may be found in the appendices. Column 2: Item.
The name of the item is listed. Column 3: Data. For each
line item the raw data is given in joules, grams, dollars
or some other appropriate unit. The source, derivation
and characteristics of the data should be shown in the
footnotes. Column 4: Solar Emergy per Unit. For many
items the solar emergy per unit (transformity where the
unit is energy) has already been calculated in previous
studies. If it has not, the solar emjoules per unit can be
calculated using one of the methods listed in Odum
(1996). Transformities and other emergy per unit ratios
including some new values, e.g., snow, taconite,
dolomite, are listed in Appendix B. Column 5: Solar
Emergy. The solar emergy is given here and it is the
product of columns three and four. It can be an emergy
flow (sej y"1) or emergy storage (sej). Column 6:
Emdollars (Em$). This number is obtained by dividing
the emergy in column 5 by the emergy/dollar ratio for
the country in the selected vear.
2.2.3 Data Sources and Model Evaluation
In general, government sources are the first priority
for environmental and economic data acquisition. For
the emergy analysis of a state, U.S. government sources
are preferred. Government sources are most likely to
provide detailed descriptions of assumptions and
methods, and they often provide a quantitative estimate
of error. Recorded data specific to the system both in
time and space are preferred. However, data are rarely
collected in a manner that can be directly inserted into
an emergy evaluation table. For example, international
trade exchanges are recorded annually by several
Federal agencies, but domestic trade is evaluated only
through surveys conducted five years apart.
Furthermore, a great deal of economic information is
recorded in terms of currency exchange, but because
unit prices vary substantially, it is difficult to estimate
the actual resource or environmental use involved. In
these cases, broader based assumptions and accepted
models, many of them models employed by economists,
are used to convert the recorded data into estimates for a
particular area or system.
The information needed for the emergy income
statement is most often reported as annual flows of mass
and/or dollars. Usually mass can be easily converted to
energy because the energy content of many objects has
been widely tabulated (1). Numbers in italics follow
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Methods
data sources mentioned in the text and refer to entries in
the Data Sources section of this report. The energy
contents of many materials evaluated in this study are
given in Appendix C. The specific emergy or the emergy
per unit mass has also been calculated for many items
and can be used to convert mass flows to emergy when
it is convenient (see Appendix B). Dollar flows can be
converted to the average emergy in the human services
associated with the good or service purchased by
multiplying the dollar amount by the appropriate emergy
to dollar ratio (Odum 1996). However, the dollar value
of something does not give an accurate estimate of its
emergy except when the work of humans accounts for
all but a small part of the emergy required to make the
item.
2.2.4 Transformities
The energy content of many items has been
tabulated; however, the information available on the
solar transformities of those items is often more limited.
Thus, the availability of data on solar transformities
often determines the ease and accuracy with which
emergy accounting studies can be performed. Many
solar transformities have been calculated (see Appendix
C in Odum, 1996 and Appendix B below, Brown and
Bardi 2001, Odum 2002), but most studies require the
calculation of new transformities or the updating of old
transformities, when the average or general value for the
transformity of an item is not appropriate to answer the
management or research question. Although several
methods for calculating transformities exist (Odum
1996), transformity calculations are commonly based on
an analysis of the production process for a particular
item, e.g., see Bastianoni et al. (2005). Global
production processes are used to determine the
transformity of planetary products like the wind, rain,
snow, and waves (Odum 1996, Odum 2000). The
relevant production processes of environmental and
economic subsystems are analyzed to determine the
transformities for particular economic or ecological
products and services. For example, the inputs to Florida
agricultural production processes for different crops
were evaluated to obtain transformities for soybeans,
grain corn, potatoes, etc. (Brandt-Williams 2001). The
transformities calculated for agricultural products by
Brandt-Williams (2001) were updated in this study and
several crops commonly grown in Minnesota (grain
corn, spring wheat, and soybeans) were evaluated.
Transformities for Minnesota crops were used in this
study where appropriate.
Transformities are determined through the analysis
of a production process or by other empirical means. All
energy inputs required for the production of an item are
documented and converted to solar joules (the available
energy inputs are multiplied by the appropriate
transformity). These emergy inputs to the process are
summed and divided by the available energy in the
product to obtain the transformity of that item in sej/J.
When many production processes are evaluated, a
distribution of values can be obtained for the
transformity of any item. The thermodynamic limits on
the efficiency of all production processes lead to the
hypothesis that there will be a minimum attainable
transformity, which results when the production process
is operating at maximum power. This minimum
transformity may approach an asymptote for a given
product or service and this minimum value indicates the
location of that item in the hierarchy of all natural
processes. In practice, when a general value for a
transformity is to be determined, a well-adapted (fast
and efficient) production process is evaluated on the
scale and in the setting under which the product is
commonly formed (Bastianoni et al. 2005). For
example, rain and wind are products of the global
atmospheric heat engine and thus their transformities are
determined through an analysis of their global
production processes (Odum 2000). In any emergy
analysis it is important to consider whether the energy
and material inputs to the system can be considered to
be of average transformity for that item. If so, the
general value for the transformity for these items can be
used. For example, electricity can be generated by many
processes (using wood, water, coal, gas, tide, or solar
voltaic cells, etc) each with a different transformity
(Odum 1996). An average value of 1.7 E5 sej/J was
determined by Odum (1996), which is close to the
transformity of electricity generated from coal-fired
power plants. The use of a general transformity for an
item is appropriate when (1) the item is representative of
the mix of production processes that determine the
mean, (2) the general value reflects the specific input,
and (3) the transformity of the particular item is
unknown or is undeterminable. It would not be
reasonable to use the general transformity for an item
when the system or process under evaluation is known
to be dependent on an inflow of higher or lower
transformity energy.
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Environmental Accounting Using Emergy: Minnesota
The earth receives energy from three primary energy
sources, i.e., solar radiation, the deep heat from the
earth, and the gravitational attraction of the sun and
moon. Odum (1996) and Campbell (2000a) developed
methods to equate these three independent sources in
terms of solar emergy resulting in the determination of a
set of planetary solar emergy baselines that depend on
how the equivalences between the independent sources
are determined. All transformities are measured relative
to a planetary solar emergy baseline and care should be
taken to ensure that the transformities used in any
particular analysis are all relative to the same baseline.
However, all the past baselines can be easily related
through multiplication by an appropriate factor and the
results of an emergy analysis do not change by shifting
the baseline (Odum etal. 2000). The baseline used in
this study is from Campbell and Odum (1998) and
Campbell (2000a), who calculated a revised solar
transformity for tidal energy that resulted in a correction
to the planetary baseline in Odum (1996) giving a new
value of 9.26 E+24 solar emjoules per year. The
transformities used in this report have either been
calculated using the 9.26 baseline or multiplied by the
appropriate factor to express them relative to this
baseline. These factors and information on baselines are
provided in Appendix B, Table Bl.l, where
transformities are also given relative to the 15.83 E+24
sej/y baseline calculated in Odum et al. (2000).
2.2.5 Flow Summary and the Calculation of Indices
The final step in creation and analysis of emergy
accounts for a system is to combine the information
from the income statement into summary variables that
are used in the calculation of emergy indices. These
summary variables are shown on the aggregate diagram
discussed above and provide a macroscopic overview of
emergy and dollar flows of the system. Other analysis
methods and tools are used in Emergy Analysis (Odum
1996, Odum 1994) but they cannot be adequately
discussed in a short report. Using the emergy analysis
tables and the aggregated figures, emergy indices are
calculated to compare systems, predict trends, and to
suggest alternatives that deliver more emergy, reduce
stress on the environment, are more efficient or more
equitable.
2.3 Creating the Emergy Income Statement
The income statement includes the following tabular
accounts: (1) renewable resources received and used
within the system and the production based primarily on
the use of those resources, (2) production and
consumption of nonrenewable resources within the
system, (3) imports into the system, and (4) exports
from the system.
2.3.1. Evaluating Renewable Resources
Renewable resources are replenished on a regular
basis as a result of the use of planetary emergy inflows
in solar radiation, the deep heat of the earth and
gravitational attraction of the sun and moon. These
primary planetary emergy inflows and the continuously
generated co-products of their interactions in the
geobiosphere comprise the renewable resources of the
earth. All renewable resources known to be important
inputs to a system are evaluated and the emergy
contributed to the system by each is determined. While
all renewable energies known to be important are
calculated and included in the table, not all of them are
included in the emergy base for a system. If all the co-
products of a single interconnected planetary system are
counted, some of the emergy inflow will be counted
twice; therefore, a general rule is that only the largest of
any set of co-products is counted in the emergy base.
This rule may be modified in certain cases by adjusting
the base used for transformities of two or more inputs
(Odum et al. 1987, Lu et al. 2007).
Rain delivers two kinds of energy to systems, the
chemical potential energy that rainwater has by virtue of
its purity relative to seawater and the geopotential
energy of the rain at the elevation at which it falls, and
both must be accounted for in an emergy analysis.
Renewable energy also enters the state or other system
through cross-border flows of energy and materials in
rivers. Renewable energy inflows to the system can be
determined at two points, (1) the point of entry and (2)
the point of use. The first of these two flow
measurements gives the emergy received by the system
and the second gives the emergy absorbed or used in the
system. For example, the incident solar radiation is
received by the system and the incident solar radiation
minus the surface albedo is absorbed. The geopotential
energy of rain on land at the elevation it falls is the
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Methods
geopotential energy received by the system, whereas the
geopotential energy of the runoff relative to the
elevation at which it leaves the state is used on the
landscape to create landforms. The chemical potential
energy of the rain that falls on the land is received, but
the water transpired is actually used by the vegetation to
create living structures on the landscape. In some cases
almost all the emergy received by the system is
absorbed, e.g., almost all tidal energy received is
dissipated in estuaries and on the continental shelf.
Long-term averages are used for the environmental
inputs to the system. An economy develops over many
years in response to the environmental energies
available to support human activities in the system;
therefore, a long-term average of environmental
variables, i.e., 10 to 50 years depending on the available
data, is used to calculate the average energy supplied to
the system from renewable sources. Long-term averages
for environmental data smooth temporal variations in
the inputs of renewable energy, which might otherwise
lead to variability in the emergy indices based on
renewable inflows. Environmental data should be
collected with comparable technologies. Sometimes,
with long environmental data sets, the technology used
to obtain the data will have changed during the period of
record. In this case, we may try to reconcile the two data
sets, or if this fails, we may use only the data recorded
using the most recent instruments, since they are
comparable. Representative averages in space and time
are also important to characterize inputs accurately.
Where there are substantial differences in environmental
inputs in different regions of a state, the differences
should be prorated by area to ensure that the most
accurate estimate of the energy input to the state as a
whole is obtained for any particular variable. For
example, mountainous areas often have a different
climate and rate of surface heat flux compared to coastal
areas. More specific methods for determining the
emergy of renewable resources are provided in
Appendix C.
2.3.2. Evaluating Nonrenewable Resources
Nonrenewable resources are storages of raw
materials that have been built-up over a long period of
time by environmental processes, but that are being used
by human activities at a rate much faster than they can
be renewed. Iron ore mined from the Mesabi Range or
ground water in the Southwestern United States, which
is being withdrawn in excess of the recharge rate, are
respectively, examples of flows of a nonrenewable
resource and of a renewable resource that is being used
in a nonrenewable manner. An emergy evaluation does
not determine the contribution of a nonrenewable
resource by the price paid for the raw material - a ton of
iron for instance - because this is not the value of the
iron itself. It is the price someone is willing to pay for
the labor, machinery, and materials required to mine the
iron. When evaluating iron as an emergy input to steel
making, for example, it is important to evaluate or
estimate the energy required by nature to make the iron
as well as the human work done in its extraction and
processing (Appendix B3.4 gives an emergy evaluation
of taconite). The solar emergy required to make a joule
of iron is its solar transformity measured in solar
emjoules per joule. Material flows are multiplied by the
specific emergy (sej/g) of the item or converted to
energy and then multiplied by the transformity (sej/J) to
obtain an emergy flow. All storages in the system that
are being used faster than they are being replaced
contribute to the nonrenewable emergy supporting the
system. This includes storages that can be used
renewably, e.g., soil, groundwater, timber.
2.3.3 Evaluating Exports and Imports
The data sources and methods used to evaluate
imports and exports will vary depending on the system.
The following methods are specific for the evaluation of
imports and exports to and from a state in the United
States. Emergy is imported and exported in three forms:
(1) emergy in services separate from any material flows
(consulting, data analysis, financial services, etc), (2)
emergy in materials entering and leaving the state, and
(3) emergy in the human service associated with the
material inflows and outflows (collecting, refining,
manufacturing, distributing, shipping, and handling).
Most of the data on the shipment of commodities
between states is collected in terms of both the dollar
value and tonnage shipped. Both kinds of data are
needed to make estimates of emergy movements
because goods have energy and emergy associated with
their creation and concentration in nature that is separate
from the contributions of human services that are
measured in the economic value of the good. Generally
for steady state conditions, the value, or the money paid
for a material at the point of use reflects the service
associated with that commodity. This dollar value can
be multiplied by the national emergy to dollar ratio for
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Environmental Accounting Using Emergy: Minnesota
the year of analysis to give a 1st order estimate of the
average emergy of the human services accompanying
the flow of imported goods. The fluxes of energy or
mass in each material flow can be multiplied by the
appropriate emergy per unit (excluding services) and the
results summed to determine the total emergy in the
import and export of the materials in goods.
Determining the emergy in goods and services
imported to and exported from a state is a difficult
problem because data on the exchange of goods and
services is collected at different points, by different
government agencies, using different methods of
aggregation and estimation. Furthermore, while imports
and exports are tracked at the national level using
shipping labels that have explicit information, the
domestic distribution of goods is determined by the
statistical analysis of survey data and other economic
modeling methods. Domestic energy shipments are the
only commodities tracked on the basis of a nearly
complete accounting of actual state-to-state movements
of the commodity. Petroleum is an exception to this
level of detailed accounting because its movements are
only tracked among regions.
The detailed export profile estimates and the overall
information on state-to-state movements of goods in the
Commodity Flow Survey (CFS) (2) and it was the
primary source used to determine both the exports from
and the imports to a state by product category. In
addition, other sources were consulted to get a more
complete accounting of goods crossing the boundary
and to check the CFS numbers wherever possible. All of
these data are available on government websites (see
Data Sources).
2.3.3.1 Determining the Emergy in Materials
Theoretically, determining the emergy in material
inflows should be straightforward; however, the data
reported are not complete. Although total dollar and
tonnage values are given for inbound and outbound
shipments in the CFS for each commodity class, some
commodity classes are missing an estimate for tonnage,
dollar value, or both. This situation occurs most
commonly because shipments are too variable to make
the average a useful parameter or because a value, if
given, would reveal information about an individual
firm. A price per ton can be estimated from the data
wherever the dollar value and tonnage are provided.
Often both dollar value and tonnage for commodities are
available for the total shipments out of a state. If the
tonnage data was missing for a commodity in the
shipments to a particular state, the price (dollars per ton)
from the total shipments was used to calculate the
unknown tonnage. Where flows are present but both
tonnages and dollar values are unreported a tonnage-
weighted export profile of commodities based on their
respective fraction of total shipments was used to
estimate the missing tonnage and to bring the total for
all commodities exported to the total reported in the
CFS (see Appendix D).
The Energy Information Administration (EIA) data
on energy movements of coal and natural gas were
estimated using all sources larger than a certain
minimum size; and therefore, these data were
considered to be more accurate and complete than the
CFS data, which are estimated from the results of a
survey of shippers. The EIA data were used to check
and replace, if needed, entries in the CFS. In addition, a
category for natural gas data was added. Natural gas
movements through existing pipelines can be
determined as well as natural gas exports or imports
from or to the state.
All materials that are prepared for shipment from a
state are reported as exported in the CFS. However,
some of these materials end up within the state of origin.
The materials actually exported from a state are
determined by subtracting the tonnage of shipments that
begin and end in the state of origin from the total
tonnage of shipments in each commodity class.
While the amount of goods imported into a state are
not directly tracked in the 1997 CFS, the destination
state for exports is reported, and consequently, the
goods imported to a state can be determined by adding
up the tonnage within each commodity class exported
from the other 49 states to the state under analysis
(Minnesota). If a state has a customs entry point, the
U.S. Customs data on imports are tabulated for each
commodity class. The interstate shipment of goods
tracked by the CFS includes all the goods shipped from
a state regardless of origin, therefore international
imports need not be included separately even for states
with ports of entry. Most of the goods coming in from
abroad are passed on directly to other states and
contribute to the nation as a whole and to the states of
destination, but they contribute little to the state where
entry occurs, if they are not used there. A preliminary
10
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Methods
analysis of the State of Maryland including the port of
Baltimore showed that emergy inflows through a major
international port may be an order of magnitude larger
than the state-to-state emergy shipments. Thus,
including these pass-through flows from the next larger
system alters the emergy indices of the state to such a
degree that they are no longer comparable to states
without major ports of entry.
The 1997 Commodity Flow Survey reported
commodities using a two-digit Standard Classification
of Transported Goods (SCTG) code. This code is
different from the Standard Industrial Classification
(SIC) and the North American Industry Classification
System (NAICS), both of which are used in U.S.
economic data reports. Both import and export data are
included in the CFS, but conversion is not necessary
unless the state has a foreign customs entry point
(Minnesota has customs entries at Duluth and along its
northern border with Canada). Imports listed by NAICS
categories were converted to SCTG categories using an
approximate conversion scheme that we developed for
several different industry classification codes (see
Appendix D, Table Dl.l). Foreign trade entering the
State of Minnesota was not considered separate from the
CFS survey of total shipments, because of the problems
observed in the Maryland study.
The emergy in materials exported from or imported
to a state is then determined by multiplying the mass or
energy flow in each commodity class by the appropriate
emergy per mass or transformity, respectively, based on
an average of these ratios for the major material items
moving in the class (Appendix B, Table B2.1). Outflows
or inflows are then summed across all commodities to
get the total emergy exported or imported.
Three key data sources for export/import calculations
are the 1997 Commodity Flow Survey (2), the
Department of Energy's Energy Information
Administration (3) and import data from the US
Customs Office and the Office of International Trade
(4). In addition, data for natural gas and coal shipments
came from Department of Energy (DOE) documents (5,
6). A step-by-step method for completing tables to
calculate exports and imports is given in Appendix D.
2.3.3.2 Determining the Emergy in Services
Services per se can be tracked along with goods and
the services required for their production using total
receipts for the different industry sectors along with
sector employment. These numbers are recorded for
both the United States as a whole and for each
individual state using the same methods, but there is no
distinction between goods and services that remain
within the state and services that are transferred to other
states. A variation of the economic base-nonbase
method was used to estimate the emergy imported and
exported in services. The information on the base-
nonbase method used in this report can be found at the
web address (7) given in Data Sources.
Economic base theory is usually employed to
analyze the growth potential and stability of an economy
in terms of its export industries (7). In this method,
economic sectors are designated as basic (exporting
sectors that are largely dependent on areas external to
the state or region for marketing their goods and
services) or non-basic (sectors whose products and
services are mainly used within the state or local region
of analysis). Once the industry data have been gathered
and the assumptions about sector behavior have been
recorded, an estimation of exported and imported
services can be made.
The underlying assumption behind the base-nonbase
method of estimation is that the aggregate demand of the
people in a nation will be satisfied by the total
production of goods and services in all sectors of the
national economy. Thus the ratio of workers in any
sector to total employment for the nation indicates the
level of economic production necessary to satisfy the
average needs of the people. The number of workers in
any given economic sector in a state as a fraction of the
total workers in that state compared to a similar ratio for
the nation is an indicator of the excess or deficit
production capacity that may exist within that sector in
the state's economy. This ratio is the location quotient
(LQ) and it can be used to determine whether a given
industry sector produces exports. If LQ is greater than
one, at least some of the sector is basic (exporting). If it
is equal to one, the sector production is assumed to just
meet local demand and there is no excess to export. If
the LQ is less than one, the local economic sector cannot
satisfy the average demand and thus it is assumed that
no net export will occur. In this study we view sectors
with location quotients less than one as potential
importers of goods and services. The formula to
calculate the LQ for employment, S, in industry sector,
i, within the economy of a state with total employment,
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Environmental Accounting Using Emergy: Minnesota
St, referenced to employment in the same industry sector
of the national economy, Nl5 with total employment, Nt,
is given below.
L0 =
(1)
The following equation was used to determine the
number of basic jobs, B, in the export portion of an
industry:
B =
(2)
The number of basic sector workers, B, times the
productivity per worker in the state industry gives an
estimate of the dollar value of exported services.
Multiplication of this number by the emergy to dollar
ratio for the nation gives an estimate of the average
emergy exported from a sector. If both goods and
services are exported from the sector, the dollar value of
the goods exported must be subtracted from total sector
exports to estimate services. Alternatively for sectors
that export both goods and services, the above method
can be applied to more detailed data from sub-sectors
that are almost entirely services and the export
determined based on these sector divisions.
An estimate of the potential import of services to a
region can be obtained in a similar manner. Under the
assumptions given above, the deficit in employment in
an industry sector should indicate the amount of service
that would need to be imported for the residents of a
region to enjoy the same level of service from these
sectors experienced by an average person in the nation.
To estimate imported services from the calculated
potential, states above the average per capita income in
the nation are assumed to be able to fill all their need for
services, whereas states below this level were assumed
to be able to fill only part of their needs. For example,
West Virginia is a state shown to be impoverished by
many social and economic indicators, e.g., in 1997 West
Virginia ranked 49th among the 50 states in per capita
income (8). Following the assumption given above, we
assumed that West Virginians could purchase services in
proportion to the ratio of West Virginia's 1997 per
capita income to the 1997 national average per capita
income. In contrast, Minnesota ranked 10th in per capita
income in 2000 and it is assumed to import all services
needed to fill any deficit. This number is only an
estimate and the actual value of services entering the
state is unknown. Assumptions governing the export and
import of services from different industry sectors might
be expected to vary somewhat based on the particular
economic circumstances of individual states. In using
this method, it is important to ascertain the facts about a
given state's economy and to make supportable
assumptions about service import-export relationships
based on those facts. Steps in the method to calculate
services are given in Appendix C.
2.4 Creating the Emergy Balance Sheet
The emergy balance sheet is a table containing the
evaluation of the emergy stored in the natural and
economic assets of the system. A partial list of assets for
Minnesota that emphasizes the storages of natural
capital is presented in this paper. The determination of
some stored assets on the balance sheet of a state or
region requires knowledge of the emergy input over the
average turnover time of the storage. For example, to
determine the emergy required for a forest of trees that
are on average 80 years-old, the average annual energy
used to support an area of forest (chemical potential
energy of the water evapotranspired) would be
multiplied by its transformity and then that number
multiplied by 80 to determine the emergy required to
develop the standing crop of trees comprising the forest.
In evaluating an economic production process, start-up
or capital costs are prorated over the average lifetime of
the facility carrying out a production process. If the
energy or mass of storage present in the system is
known, this quantity can be multiplied by its
transformity or specific emergy to obtain the emergy of
the stored asset. For example, the estimated recoverable
iron reserves in grams could be multiplied by the Gibb's
free energy J/g to get energy and then by the
transformity of iron (sej/J) to find the emergy of the
stored capital asset. In this study environmental
liabilities (Campbell 2005) are only partially accounted
for on the emergy income statement and thus are not
placed on the balance sheet; however, methods to better
document them are under development and we plan to
include these accounts fully in future studies. Also, the
data to quantify the economic infrastructure of a state in
physical units is not commonly tabulated, and thus, we
12
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Methods
are looking for data sources and methods to easily
quantify the economic infrastructure and assets of
society present within state borders.
2.5 Constructing the Emergy-Economic
Overview
Information from the completed emergy income
statement tables is combined to create a Table of
Summary Flows, which provides the quantities needed
for the calculation of the emergy indices. These
summary flows are also placed on the aggregated
overview diagram of the system. The item name often is
sufficient to identify a quantity, but where it is not,
additional explanation is given in the Table notes along
with how the quantity was derived. The evaluated
energy systems diagram of the macroscopic economic
and ecological features of the system shows important
classes of flows, the details of emergy and money
movements across system boundaries, and a limited
number of flows within the state. The inflows of
renewable and purchased emergy and the outflows of
emergy in products and services are summarized in an
even simpler "3-arm diagram" that shows only the
inputs and outflows from the system.
2.5.1 Summary Emergy and Dollar Flows
The summary table includes information on all the
important emergy and dollar flows of the system
designated with a letter for each category of flow.
Numerical subscripts after a letter or symbol denote a
particular flow of a given type. The renewable energy
inflow to the system is designated with the letter "R".
The letter "N" indicates nonrenewable energy sources
and it includes "N0", which designates ordinarily
renewable sources that are being used faster than they
are replaced, e.g., soil, timber, or groundwater. The
letter "F" designates flows of fuels and minerals
imported to and/or used within the state. The gross
economic product of the state (GSP) is designated with
the letter "X". The letter "G" designates imported goods
excluding fuels and minerals. The dollars paid for all
imports are shown with the letter "I", and subdivisions
of this sum are given by subscripts. The dollars brought
into the state as Federal transfer payments are listed with
other dollar inflows. The letters "PI" designate the
emergy flows in human service that have been
purchased by the dollars paid for imported goods and
services. Exported products are represented with the
letter "B". The dollars paid for exports are shown with
the letter "E" whereas the emergy of the human service
required to produce these exports is shown as "PE".
Other flows can be added, e.g., immigration, when they
represent major inflows of emergy in the annual budget.
Money entering the state does not bring emergy into
the state unless it is spent on goods, fuels, or minerals
from outside sources. However, when money from
outside is spent in the state, this money generates
internal emergy flows. For example, the emergy flows
generated when tourist dollars are spent in the state are
included as emergy exports. Campbell (1998) argued
that tourists receive value from their recreational
experience and that these experiences are virtual emergy
exports, which require that unique emergy storages and
flows exist within the system to attract tourists and their
expenditures. Tourist's expenditures within the state are
taken as a first order estimator of the value of the
recreational experience that they take home with them.
Recreational experiences are classified as exports,
because they would not be possible without the unique
opportunities provided by the emergy stores and flows
that are present in a given area.
One research question of interest is, "Are Federal
transfer payments linked to the overall emergy received
by the nation from a state?" If so, Federal transfer
payments might be larger if the real value received by
the Nation exceeds that expected from the monetary
exchange, i.e., the monetary exchange balances but the
emergy exchange does not. This relationship has not
been proven, but Federal outlays add emergy flows to
the state when these monies are spent within the state,
i.e., at the state's emergy to dollar ratio. In this latter
view Federal outlays are imports and Federal taxes are
exports because they represent a foregone opportunity to
generate emergy flows within the state. In this paper we
examine the question of Federal outlays and taxes more
closely by analyzing the structure of Federal outlays and
taxes in Minnesota and by comparing Minnesota to
West Virginia.
2.5.2 Determining the Renewable Emergy Base for a
System
The objective in determining the renewable emergy
base for a given area of the earth is to evaluate the
degree to which the earth's renewable emergy sources
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Environmental Accounting Using Emergy: Minnesota
have been concentrated in a given area. All significant
inflows are identified and evaluated, but the items
included in the renewable emergy base for the system
are determined in a manner that avoids double counting,
i.e., the base includes only the largest of the emergy
sources entering the area when they are co-products of
the same generating process. For example, rain and
wind are co-products of the work done by the planetary
heat engine (the latitudinal gradient of temperature over
the world oceans); therefore, only the largest would be
counted toward the renewable emergy base for a given
area. If a system includes land and sea areas, the
renewable emergy base can be determined for each area
and the two inputs summed to obtain the renewable
emergy base for the entire area.
Planetary processes are considered to be one
interconnected system for the purpose of determining
the transformities of global products, thus the entire
emergy input to the earth is necessary for the formation
of all global co-products, regardless of the baseline. As a
result the rules to minimize double counting in
determining the natural emergy base for a given area of
the earth will be the same for all baselines. A simple
rule to avoid double counting when using the 15.83 or
the 9.26 baseline is to only count the largest inflowing
emergy of all the co-products of the planetary system
(including tide) as the emergy base for any given area of
the earth. Under this rule different areas in the same
system may count different single emergies as the direct
base, e.g., tide for a state's area of coastal ocean and the
chemical potential energy of rain for the land area of the
coastal state can be added together to get the renewable
emergy received by the entire area of the state. The
same spatial resolution for determining the emergy
inflows must be used to ensure that bases are
comparable. Where emergy inflows are concentrated in
space, higher resolution of the inputs will result in a
greater emergy base for the system. For example, at a
resolution of 100 m, the zone of breaking waves would
be resolved for a coastal system and the wave emergy
absorbed might be added to the emergy base for the
system after adjustment of the area of the other inputs,
and if it is the largest input received over the area of the
100 m coastal strip. This dependence on spatial
resolution requires that the emergy analyst consider
differences in the emergy signature across the landscape
where they exist, thus areas of different biogeographic
characteristics are considered separately and the largest
emergy inflows to each are combined to represent the
total system (Campbell 2000a).
With regard to determining the emergy base for a
system, the main purpose of the emergy accounting is to
include all the emergy required for a system without
double counting any input. The rule to only count the
largest input among co-products is a crude way of
ensuring that no double counting occurs; however, this
method gives a conservative estimate of the emergy
required for the system. In fact, co-products may have
only partial dependencies and where the relationship
between these inputs is known other solutions can be
used (Odum et al. 1987, Lu et al. 2007). How to handle
partial dependencies among system inputs is being
investigated in current research on emergy methods.
(A) Renewable emergv received. For any area, use
the largest of the energy sources supplied by the
planetary processes (rain, wind, waves, earth cycle,
tides, etc) at the point that they enter the system and
sum over the entire area to determine the renewable
emergy received. For rivers that cross into a state or
flow along its borders, the emergy received at the point
the river enters the state is included in the emergy base.
If the river flows along the border between two states,
!/2 of the emergy received is given to each state.
(B) Renewable emergy absorbed. Both the emergy in
chemical potential energy (evapotranspiration) and the
geopotential energy (runoff) of water doing work in the
system are counted, because these two forms of energy
carried by water interact across the elevation gradient
from mountains to the sea to maximize empower on the
landscape (Romitelli 1997). All tidal energy received is
assumed to be used within the estuarine and continental
shelf area and all wave energy is assumed to be used
when waves break on the shore. The chemical potential
and the geopotential energy of rivers used in the state is
found by determining the chemical and geopotential
energy at the point where the river leaves the state and
subtracting this from the respective potentials at the
point of entry. For example, a river enters the state 500
m above sea level and leaves at an elevation of 250 m,
the difference in geopotential energy of the annual water
flows at these two points is the geopotential energy used
within the state.
2.6 Emergy Indices
Emergy indices are often helpful in characterizing
the condition of a region and in determining the
relationship between the region and its larger system.
14
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Methods
The emergy indices are calculated by performing
various mathematical operations with the quantities
given in the Flow Summary Table. The indices used in
the emergy evaluation of Minnesota are identified and
explained below.
2.6.1 The Emergy/Money Ratio
The ratio of annual emergy flow to money flow is a
useful index because it connects economic activity to
the emergy flows that support the economy in a given
year. An emergy to money ratio is obtained by dividing
the total emergy used by a state or country in a given
year by the gross economic product for that year. The
result gives the average amount of emergy that is
purchased by spending a dollar in a certain place (sej/$)
at a given time. In other words the emergy/dollar ratio
tells us the purchasing power of a dollar in terms of the
real wealth (emergy) that it can buy. Money is used to
purchase products such as food, fuels, clothing, housing,
electricity, information, etc. according to their market
price. Each of these products also has an emergy value.
In addition, many products of nature contribute to these
economic products but are not traded in the market and
thus have no market value. Dividing the emergy of a
product or service by the emergy to dollar ratio for its
system gives the emdollar value of the item. The
emdollar value of a product or service represents the
portion of the total purchasing power in the system that
is due to a particular product or service from the
economy or from nature. The emergy to dollar ratio has
another useful property. Since dollars are only paid to
people for their services, the emergy to dollar ratio for a
system can be used as an estimate of the average value
of human services in that system. Thus, multiplying a
dollar value of a product or service by the emergy to
dollar ratio gives, on average, the emergy equivalent of
human service required for an item.
2.6.2 The Emergy Exchange Ratio
The emergy exchange ratio (EER) is the ratio of
emergy received to the emergy given in any economic
transaction, i.e., a trade or sale. The trading partner that
receives more emergy will receive greater real wealth,
and therefore, greater economic stimulation due to the
trade. Indices of equity in exchange between states and
nations are determined by comparing the emergy in
imports and exports. The difference between imports
and exports indicates whether the state or region is a
support area for other regions and/or the larger system.
The ratio of exports to imports indicates the degree to
which a system contributes emergy to or receives it from
a trading partner or its larger system. When applied to
individual products, the EER gives the emergy
advantage to the buyer by determining the emergy of the
exported product relative to the emergy that could be
purchased with the buying power of the money received
in exchange.
2.6.3 The Investment Ratio
The investment ratio is the ratio of the solar emergy
purchased from outside the system to the solar emergy
supplied by the renewable and nonrenewable energy
sources from within the system. It shows the matching
of economic investment to the indigenous resources of a
state or region. Lower values of this ratio indicate that
more of the indigenous environmental resources are
available per unit of economic activity than the average,
and therefore, environmental resources may be available
locally and capable of stimulating investment and
additional economic use. The ratio of purchased to free
emergy is a variation of the investment ratio, which
compares purchased emergy with the free contributions
of renewable emergy (e.g., rain) and renewable emergy
used in a nonrenewable manner (e.g., soil erosion).
Empower density or the emergy flow per unit area is a
related measure that indicates the spatial concentration
of economic activity or the intensity of development in
any unit area of a state or nation.
2.6.4 The Environmental Loading Ratio
The environmental loading ratio is the ratio of the
emergy used from nonrenewable sources (including
renewable sources being used in a nonrenewable
manner) and the emergy imported in goods and services
to the renewable emergy used (Odum 1996, Brown and
Ulgiati 2001). It indicates the expected intensity of
impacts that must be carried by the renewable emergy
base of the system, and therefore, the probability that the
system will have incurred significant environmental
liabilities on the balance sheet.
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Environmental Accounting Using Emergy: Minnesota
2.6.5 Indices of Self-Sufficiency and Dependence
The emergy used from home sources as a fraction of
total emergy use is a measure of the relative self-
sufficiency of a state or region. Conversely, the fraction
of total emergy use purchased from outside shows the
dependence of a state or region on the larger economy
of which it is a part. The fraction of use that enters as
imported services indicates the relative dependence of
the state on the service economy of the nation.
2.6.6 Indices of Sustainable Use
The fraction of use that is free and the fraction of use
that is renewable are indicators of what is sustainable in
the long run. If the difference between these two
indicators is large, it shows that the long-term capacity
of the renewable emergy sources to support life is being
degraded. Truly sustainable use is based on renewable
resources alone used in a renewable manner. A quick
estimate of the renewable carrying capacity of a state at
the current standard of living is obtained by multiplying
the fraction of use that is renewable by the present
population of the state. Sometimes the developed
carrying capacity at the current standard of living is also
estimated by multiplying the above number by 8, an
average ratio of purchased to renewable emergy in
developed countries from past studies (Odum 1996).
Eventually, this number will be modified based on the
current set of state studies.
2.7 Energy and Emergy Signatures
Energy and emergy signatures of a system show the
magnitude of environmental and economic processes as
a synoptic plot that is useful in characterizing and
classifying systems. The energy signature is a bar graph
of energy flows with the magnitude and direction of the
flow (in or out of the system) in joules per year shown
on the ordinate and the type of energy flow identified on
the abscissa listed in order of increasing transformity. A
bar graph of the same flows converted to empower
(sej/y) is the emergy signature of the system.
Conversion of energy flows to empower shows the
relative contributions of the various energy inputs in
terms of equivalent ability to do work. If functionally
distinct areas have different emergy signatures
(Campbell 2000b) and similar areas exhibit similarities
in their emergy signature, the emergy signature may be
useful in classifying different environmental systems
based on differences in their inputs (Odum et al. 1977).
2.6.1 Indices of Quality of Life
The annual emergy flow per person is hypothesized
to be an index of the overall standard of living that
includes environmental and economic contributions to
the quality of life. This assumes that the people living in
the system actually benefit from the energy used there.
Quality of life is also indicated by the emergy in
electricity use as a fraction of total use. This ratio is a
measure of the relative importance of the higher
transformity activities of people, and therefore, it should
be correlated with the contributions of technology to
higher standards of living. Other emergy indices of
quality of life need to be developed that better capture
the human-information aspect of well-being.
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An Emergy Evaluation of Minnesota
Section 3
An Emergy Evaluation of Minnesota
An emergy analysis of the State of Minnesota is
given in this section of the report. The application of
emergy analysis methods in this state study shows
how each of the techniques given in the methods
section is performed. The assumptions, calculations
and data sources used in each part of the analysis are
documented and given in the Appendices. This section
is written as a stand alone report that can be used by
scientists and managers who are interested in the
results and conclusions of this case study, "Emergy
Evaluation of Minnesota."
3.1 Introduction
The economic productivity and well-being of
Minnesotans are dependent on the health and vitality
of their environment as well as the wealth of their
stored natural resources. However, the environmental
contributions to Minnesota's economy cannot be
evaluated using market values alone. This is true
because there is an inverse relationship between the
contribution that a resource makes to the economy and
its price (Odum 1996). For example, when timber is
abundant, prices are lowest but the contribution of
timber to society is greatest because it is used in great
quantity and for many purposes. On the other hand,
after extreme logging of a region, timber becomes
scarce and the cost increases; timber contributes less
to the economy, because it is no longer commonly
used (Odum 1996). Economic studies evaluate wealth
by what people are willing to pay for a commodity or
service, but because money is not paid to the
environment for its work, market values do not
effectively assess environmental contributions to
society (Odum, 1996). Emergy includes nature's
work contributions to economic products and services.
Emergy accounts can provide directly comparable
estimates of the environmental, social and economic
costs and benefits of alternative actions. Therefore, the
creation and analysis of such accounts is needed to
ensure that managers have all the information that
they need to make decisions in the best interest of
society.
At present, Minnesota is faced with the conflicting
needs of its people and the nation. There is a national
energy policy initiative for the United States to reduce
its dependence on foreign sources of energy (National
Energy Policy Development 2001). At the same time,
there is a growing recognition of the need to establish
a sustainable relationship between society, resource
use, and the environment (National Research Council
1999). If a constant standard of living is to be
maintained in the United States as global petroleum
production declines, fuel autonomy implies an
expansion of national energy production and
economic growth for Minnesota and other states with
a rich abundance of natural resources. However, there
are thought to be large environmental and social
impacts associated with the use of Minnesota
farmland to produce biofuels such as corn-based
ethanol (Pimentel 2003). Minnesota is currently
subject to national legislation calling for the increase
of ethanol production. The need to increase corn
production to make ethanol will compete for arable
land with other food crops and prices for both corn
and the displaced crops will increase. Emergy
analyses of ethanol production from various feed
stocks and technologies will help clarify the
consequences of greatly increasing ethanol production
in Minnesota and in the Nation as a whole. Minnesota
is also under internal pressures to increase economic
prosperity through further developing its human and
natural capital resources while also confronting the
daunting task of preventing agricultural and industrial
development from further damaging the health of
human beings and the environment.
Human economic activities such as mining,
timbering, farming, and changing patterns of urban
and industrial growth are the primary forces causing
environmental change in the State. Major
environmental problems in Minnesota include point
and non-point pollution from agricultural activities
and urban development, e.g., effluents from
agricultural and industrial manufacturing facilities,
sediment accumulation in streams, nitrogen in runoff
from farm lands, as well as invasion of exotic species,
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Environmental Accounting Using Emergy: Minnesota
forest fragmentation, and habitat loss that accompany
these and other human activities (9). Because of its
many lakes and wetlands, the aquatic environment is
of special concern to Minnesotans, especially the
deposition of mercury and its accumulation in game
fish (M. Bourdaghs, pers. com.). In this report, we
examine the larger system that controls the
environmental and socioeconomic characteristics of
local systems within Minnesota. The results of this
study can serve as the context for the analysis of the
sustainability of regional and local systems. In
addition, the emergy analysis methods used in this
state-wide study can be applied to characterize
environmental and socioeconomic problems at the
local and regional scale and to evaluate alternative
solutions for watershed restoration.
3.2 The Efficacy of Emergy Accounting in
Answering Management Questions
People need accurate and complete financial
information to answer questions about their fiscal
condition, so that they can make better decisions. The
kinds of questions that can be answered by keeping
accurate financial accounts are many and depend on
the particular system for which the accounts are being
kept. For example, people ask and answer practical
questions about their individual finances every day.
Some of these questions relate to the amount of assets
or income, e.g., "How much money do I have in the
bank?" or "Are my monthly expenditures within my
budget?" Other questions relate to the equity of
exchange, e.g., "Is that used car really worth the
money?" or "How much will the schools improve if
my property taxes go up?" Still other questions are
social in nature and relate to how we are doing
compared to others, e.g., "Do we have a higher or
lower standard of living than the neighbors?" When
the questions relate to financial condition, dollars are
sufficient to provide the answer. However, where
resources in the public domain are being used,
degraded, or developed, questions about
environmental systems cannot be answered by
considering monetary value alone. Yet the health of
society depends on accurate answers to questions
about the condition and use of environmental
resources as surely as individual financial health
depends on assessing personal savings and income.
Standard accounting tools, such as the income
statement and balance sheet, are used to document the
financial health of a firm. It is no less important that
we develop similar tools to assess the condition of
environmental systems. Emergy accounting provides
the means to keep the accounts for the economy,
society, and the environment on a single income
statement and balance sheet. The questions that we
can answer after performing an emergy analysis of a
system are similar to those that we can answer as a
result of doing a financial analysis of a business or of
our own individual accounts. The following key
questions to be answered from information on
Minnesota's environmental accounts were derived
from discussions with environmental managers from
Region 3 and they are the same questions used in the
West Virginia study: (1) "What is the current level of
economic investment in relation to Minnesota's
resource base, and is this level of investment
sustainable?" (2) "What is the net exchange of real
wealth between Minnesota and the nation?" (3) "What
are the major causes for any observed imbalances?"
(4) "What actions can be taken to address an
imbalance, if it exists?" (5) "How does Minnesota's
standard of living compare to other states and the
Nation?" (6) "Who benefits most from the productive
use of the state's resources?" (7) "How self-sufficient
is the state based on its renewable and nonrenewable
resources?" (8) "How can we manage the environment
and economy of Minnesota to maximize the well-
being of humanity and nature in the State and in the
Nation?" The emergy accounts for Minnesota
presented below will provide information and
indicators that will help answer these questions.
3.3 Narrative History of the Land, People and
Natural Resources of Minnesota
Before considering in detail the condition of the
State of Minnesota in 1997 and 2000, we briefly
review the history of the State. Environmental systems
like Minnesota are composed of the land, the people,
and natural resources and it is our understanding of
the development of all aspects of the system that
allows us to accurately interpret the present and plan
for the future. The following section presents a brief
narrative history of the land, people, and natural
resources of Minnesota, which is manifested today in
the structure of environmental, economic and social
systems in the State.
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An Emergy Evaluation of Minnesota
The real wealth of Minnesota can be found in the
hard work and ingenuity of its people and in the
emergy stored in its abundant natural resources. We
first consider the geological history of the State and
the development of its landforms and mineral
deposits. The entire geologic history of Minnesota is
not entirely clear but it is apparent that Minnesota has
not always been prairies, rolling hills, and vast forests.
Many of the physical features of Minnesota as seen
today took millions of years to form and the land that
makes up Minnesota has gone through billions of
years of change. At times it rested on the equator; it
has been the host to great inland seas, and it has been
subjected to several periods of glaciation. In the last
150 years geologists have pieced together a great deal
of the State's past (Ojakangas and Matsch 1982).
Some of the oldest rocks in the world are found in
Minnesota. Called gneisses, they are approximately
3.6 billion years old. The oldest gneisses on Earth are
found in Greenland and Labrador and these were
formed in the pre-Cambrian era only 200 million
years before those of Minnesota. Mountains and
volcanoes are not something that Minnesota is known
for today, but there were several periods of volcanism
in Minnesota's geologic history. All that is known of
the ancient volcanism is found in gneissic super belts
that formed around 2.7 billion years ago. Minnesota
was covered with large mountains due to volcanism at
two points, 2.7 and 1.8 billion years ago. There was
another period of volcanism in the State around 1.1
billion years ago, but this did not have a dramatic
effect on the landscape. After the volcanism the
terrain was subject to a great deal of folding. Next,
large bodies of granitic magma intruded into and
metamorphosed the volcanic and sedimentary rocks.
Upon solidification of the granite, faulting began,
creating rifts in the old sheets of rock. This
combination of folding, intrusion, and faulting was
responsible for forming the mountains in northern
Minnesota. Since then, the land of Minnesota has been
stable and free of violent geologic events. Erosion
wore down the land and the mountains in the Lake
Superior region over millions of years. The State lies
on the Laurentian Upland and Interior Lowland of
North America, which are two stable areas of low
relief that are perhaps responsible for this long period
of stability and erosion in Minnesota (Ojakangas and
Matsch 1982). Within the last billion years, the State
has been repeatedly covered with oceans; proof of this
lies in the many layers of sandstone, shale and
limestone within the State and the marine fossils that
are found in some deposits.
The large iron deposits found in the State are from
the pre-Cambrian era and they were formed from
sediment deposition in an ocean that covered the land
around two billion years ago. The middle-pre-
Cambrian was a time when massive iron deposits
were laid down in many shallow seas around the
world, presumably by the action of iron-fixing
bacteria (Ojakangas and Matsch 1982). The great
prevalence of iron deposition at this time has been
attributed to the low oxygen atmosphere that is
presumed to have existed, before photosynthetic
organisms came to dominate the earth.
Around 250-550 million years ago during the
Paleozoic era, a transcontinental arch ran through
Minnesota creating an area that could not be
submerged by most of the subsequent invading
oceans. Therefore there was very little deposition in
Minnesota during this time and none at all through the
center of the State. Also, during the Mississippian and
Pennsylvanian periods the equator ran through the
area that is now Minnesota. About 100 million years
ago, an ocean invaded western North America and its
eastern shoreline passed through Minnesota. Life
flourished through the State in the Cretaceous period
and led to small deposits of coal, but nothing that can
be mined economically today.
From 75,000 to 10,000 years ago, glaciers covered
Minnesota with ice that was several kilometers thick
in some places. These glaciers were responsible for
creating much of Minnesota's current landscape.
During one stage, the glaciers extended south as far as
Kansas, which is evidenced by glacial, erratic
boulders found there that match Minnesota's bedrock.
As the glaciers finally receded, several glacial lakes
formed over Minnesota with the largest being Lake
Agassiz. This lake formed on the western edge of
Minnesota and extended into the Dakotas and Canada.
Before the glaciers melted enough for the lakes to
drain to the north, the water had to flow south and
eventually spilled over the moraine which formed the
southern boundary of Lake Agassiz. This draining
action wore away a valley creating the Glacial River
Warren, while at the same time depositing sediment.
Eventually the glaciers melted enough to allow water
to drain to the north into Hudson Bay. As this
happened, the Glacial River Warren ceased to flow
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Environmental Accounting Using Emergy: Minnesota
south and the Minnesota River began to flow in the
glacial river's broad valley. Because the Minnesota
River is many times smaller than its predecessor, it
was able to wear away a deep valley in the loose
sediment that the Glacial River Warren had deposited.
The Mississippi River formed in much the same
manner from smaller glacial lakes draining south. The
resulting feature is that both rivers have wide flood
plains and fertile river valleys. In the north, oxygen
poor water and cool temperatures allowed peat to
form easily on the poorly drained lands that had been
covered by Lake Agassiz and other glacial lakes until
around 5,000 years ago.
Even though the land had been subject to geologic
forces for billions of years, one of the greatest forces
that would alter the landscape had yet to arrive. For
several thousand years before the present time, people
inhabited the area that became Minnesota; however,
they lived a low impact existence relative to today's
industrial civilization. Ever since white Americans
and Europeans began to settle in Minnesota in large
numbers during the mid-1800s, the land has been in
constant change. Nearly all of Minnesota's forests
have been clear-cut at least once, and less than one
percent of the original prairie remains (Tester 1995).
The history of the people of the State is complex,
but it behooves us to consider it, if we are to
understand the basis for present social structures and
mores. The following account of the history of the
people of Minnesota draws heavily on Theodore C.
Blegen's "Minnesota, A History of the State" written
in 1963.
The northern and southern halves of the State were
separated by a vast expanse of wilderness, and as a
result, they have notably different histories. Europeans
arrived by boat from the south, coming up the
Mississippi River and from the north, they found their
way to Minnesota by canoe crossing Lake Superior.
The Europeans and white Americans who arrived
using these different access routes had very different
resource exploitation goals, and these goals
determined the different course of development in the
north and south.
For centuries prior to European settlement, Native
American tribes lived in Minnesota. In the north, the
Sioux and Chippewa constantly battled, contesting the
boundaries of their lands. Then in the mid-1600s, the
French arrived in the northern region in search of furs.
The French sided with the Chippewa and aided them
in their battle against the Sioux. Eventually, with guns
and new tactics learned from the French, the
Chippewa drove the Sioux out of the forests of
northern Minnesota and onto the Great Plains of
southwestern Minnesota and the Dakotas. The French
entrenched themselves in the region when they
annexed the entire Lake Superior region, including
part of Minnesota. The French presence lasted until
1763 when northeastern Minnesota was given to the
British through the Treaty of Paris at the end of the
French and Indian War. During the American
Revolution, British soldiers made a brief show of
force in the region by arriving at Grand Portage in
1778. This was the only involvement of the region in
any part of that war. After the war, Britain ceded
control of all land south of the Boundary Waters Area.
Despite the cession of this territory to the United
States, the British maintained control until after the
War of 1812.
The displacement of the Sioux in the north
eventually created conflict with the advancing settlers
as they began to occupy land in southern Minnesota.
This desirable area included good farmland that lay
along the Mississippi and Minnesota Rivers. In 1851,
thirty-five Sioux Chiefs signed a contract with the
Territorial Governor, Alexander Ramsey, giving a
large portion of their land along the Minnesota River
to the Americans but retaining small portions of land
for themselves in the upper reaches of the Mississippi.
The Americans were supposed to pay the Sioux a cash
settlement, but that was given to investors assuming
they would make money on their investments and
with that buy food, medicine, and other necessities for
the tribes. In 1861 and 1862, conditions on the
reservations deteriorated because of the failure to
deliver the promised food and supplies and conflict
between the tribes broke out. As the situation
worsened, Chief Little Crow, whom both Sioux and
Americans respected, approached the agent in charge
of the reservation to negotiate food and supplies.
When the Chief was rebuffed by a trader, the tribes
retaliated by murdering five white settlers and
declaring war the next day. The Sioux Uprising of
1862 lasted for five weeks and was eventually put
down by a force led by Henry Sibley from the Twin
Cities. As many as 800 settlers and soldiers died in the
uprising along with an uncounted number of Sioux.
In the wake of the uprising, 300 Indians were
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An Emergy Evaluation of Minnesota
sentenced to death. President Lincoln intervened and
he pardoned all but 38 Sioux who were eventually
hanged. As a result of this uprising, Minnesota exiled
all remaining Sioux from the territory and forbade
their return.
Exploration of the southern part of the State began
in 1680 when Father Hennepin, a Franciscan priest
entered Minnesota from the south. He was the first
European on record to arrive at and name the Falls of
St. Anthony, which are at the heart of Minneapolis. In
1805, Zebulon Pike on orders from the United States
Government purchased land from the Native-
American tribes around the falls of St. Anthony.
Settlement in the territory by white men began in 1820
with the completion of Fort St. Anthony, now known
as Fort Snelling. The settlement around Fort Snelling
offered an oasis of American civilization in the
wilderness to travelers and St. Anthony Falls became
one of the best-known tourist attractions in the
northern United States. The first mills were built along
the banks of the Mississippi at the St. Anthony Falls
from 1821 to 1823. This was the beginning of a long
history of exploiting the waterfall for its power. This
event also marked the beginning of grain and lumber
milling industries that would form the basis of a
thriving economy in Minnesota for the next hundred
years.
Initially, the falls and the land surrounding them
were in the hands of the military, but by the 1830s the
potential for private use of the land was realized and
the military used its right of ownership to expel the
nearly 200 squatters that had made their home on land
belonging to the Fort. The displaced squatters left the
"Falls" area and made their home eight miles down
stream on Pig's Eye Island, named after a well known
whiskey seller of the time. This island eventually
became the city of St. Paul. In 1837, the government
negotiated a deal with the Chippewa and Sioux that
opened up the entire area of land between the
Mississippi and the St. Croix Rivers to settlement. As
soon as the treaty had been ratified by Congress,
Minnesota's first land rush began. One of the people
awaiting the news of ratification was Franklin Steele.
He was determined to gain control of the eastern half
of St. Anthony Falls so he could claim half of the
river's water power for himself. Along with his
business partners he already owned a large portion of
the St. Croix Falls. At this point, timber was being cut
quickly along the St. Croix River; however, logging
had not made its way to the rich stands of trees along
the Mississippi. Steel knew that since he owned the
land and half of the falls, he could make a fortune if
he built mills. To do that he needed capital, so he
found several wealthy politicians from Massachusetts
to fund his venture. This led to the first civilian dam
on the river and resulted in the construction of mills at
the Falls of St. Anthony.
In 1848 President Polk initiated the first land sale
in the Minnesota Territory. Steele purchased another
332 acres of land around the falls and strengthened his
claim. Once people started moving to the area, Steele
was able to establish the township he had been
envisioning from the beginning. Because St. Anthony
Falls was too long of a name to fit on a map, the
settlement on the east bank of the Mississippi became
St. Anthony.
The early 1850s ushered in the era of forest clear-
cutting in the Mississippi watershed, creating a steady
flow of timber down the river to the booming milling
industry at St. Anthony Falls. Eighteen fifty-one also
brought a glimpse of the future when the first grist and
flour mill was built in the settlement. The era of
commercial flour milling began with the erection of a
commercial grinding mill in 1854.
At the same time, Minneapolis was becoming a
city across the falls. For many years, the western side
of the falls was the property of Fort Snelling and the
potential of the western half of St. Anthony Falls was
not realized. This changed when Robert Smith, a
congressman from Illinois, petitioned the Department
of War to lease the lumber and grist mills and the
house that had been built in the 1820s to supply Fort
Snelling. Despite never actually moving to Minnesota,
Smith kept up the facade that he was living there and
the Secretary of War believed him. Steele was also
attempting to gain a foothold on the western side of
the river. He managed this by constructing a ferry at
the falls and having one of his former employees settle
on the western shore. This became the first residence
on the land that would become Minneapolis. In 1852
Congress passed a bill that would open up over 2/3 of
the 34,000 acres included in Fort Snelling to private
auction. Several years after the auction, the city of
Minneapolis was born. The two cities of Minneapolis
and St. Anthony worked together on many things
including building the first suspension bridge across
the river at the falls in 1855 and competing with
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Environmental Accounting Using Emergy: Minnesota
St. Paul, which had become a formidable rival as the
head of navigation for the Mississippi. The rivalry can
clearly be seen as early as 1850 when a resident of St.
Anthony, Paul R. George quoted, "man made Saint
Paul, but God made Saint Anthony." Because all three
cities relied on the river for their livelihood to a
similar degree, their future was to be decided by the
people who controlled the businesses of the area.
In the mid-1850s several corporations were formed
around the falls. The first was the St. Anthony Falls
Water Power Company, which was formed by Steele
in St. Anthony. Another corporation was formed on
the opposite bank by Smith, and was called the
Minneapolis Mill Company. Working together these
companies headed up the construction of the second
dam over the falls. At over 2,200 feet long, this was a
major project that changed the face of the falls
forever. After the construction of the dam, mills were
able to more efficiently harness the power of the water
and businesses around the falls grew quickly. Over the
next two decades, as Minnesota became a state, the
area around the falls changed dramatically. The cities
grew rapidly as did the number of mills that relied on
waterpower. Until around 1870 lumber milling was
Minneapolis and St. Anthony's main industry, but
second was flour milling and it was rapidly catching
up. Between 1860 and 1869 flour production rose
from 30,000 barrels to 256,100 barrels. It was
bolstered by the increase in grain being grown in the
southern and western parts of the State. At the same
time, residents of the two cities began to realize that
one city around the falls was ideal and Minneapolis
and St. Anthony became one in 1872.
Minneapolis was quickly becoming one of the
largest producers of flour in the world and in 1880 it
surpassed St. Louis as the largest flour milling center
in the country. The two main reasons for this were its
abundant waterpower and newly constructed railroads
that opened some of the finest land in the country for
farmers to produce wheat. The largest of the mills that
were built in Minneapolis was the Pillsbury A mill;
this was also the largest mill in the world at the time.
Though sawmilling fell behind as the leading industry
in the city around this time, Minneapolis remained
third in the Nation in total lumber production. To
bolster flour production, the lawmakers began to pass
laws giving flour millers an unfair advantage.
Eventually this forced lumber mills out of the falls
area and into north Minneapolis where they utilized
steam instead of water for power. Minneapolis would
hold on to the top flour production ranking for the
next fifty years.
In the late 1800s, the waterpower of the falls began
to be converted to hydroelectric power generation.
This metamorphosis would last until 1960 when the
last water wheel was taken down. Through this time,
the resource of the falls was managed by an engineer
named William De La Barre. He was primarily
responsible for transitioning the use of waterpower
from era to era as technology improved and needs
changed. Before 1960, flour milling fell by the
wayside and total production was a fraction of what it
had been in its heyday. As milling moved away from
the falls, the Hennepin Island hydroelectric power
plant took over the newly opened waterway. Today,
only the Pillsbury A Mill remains as a working mill.
In 1963 the Army Corps of Engineers finished a lock
and dam by-passing the Falls and opening the river
above the falls to the sea for the first time. Since this
time, Minneapolis has held its place as the largest city
in Minnesota and as the cultural and commercial
center for the upper Midwest.
In the late 1800s Minnesota began to transform
through rapid development of agriculture, industry,
and education. The emphasis on wheat growing
shifted toward other crops such as barley, oats, and
corn. Dairy farming increased along with milk, butter,
and cheese production under the organizing influence
of cooperative creameries. Livestock production
increased in the State and St. Paul became an
important terminal for shipping livestock and later a
center for meat packing. During this time Minnesota
society began to create supporting institutions such as
the cooperative mutual insurance companies for
farmers and dairy men that formed as early as 1867.
The cooperatives began to take on other tasks such as
advertising, and by the 1920s Land O' Lakes Inc. had
made the Minnesota Co-operative Dairies Association
the largest marketer of butter in the world. The
cooperative idea spread further extending into
cooperatively run grain elevators and as far as
consumer cooperatives. From its beginning the
cooperative movement in Minnesota was allied with
the interests of the working person (Blegen 1963).
Cooperatives spread into many businesses including
cooperative wholesalers, insurance companies,
telephone, farm supplies, and credit unions.
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An Emergy Evaluation of Minnesota
Education played an important role in the
transformation of Minnesota agriculture. County
agents working within agricultural extension programs
that were mandated by Federal law in 1914 publically
disseminated new information to farmers that
promoted modern farming methods and technological
advances. As Minnesota farms became some of the
most productive in the Nation, the food processing
industry located canneries and freezing facilities
throughout the agricultural regions of the State. In the
years since 2000 the use of Minnesota corn for
industrial production of ethanol has gained
prominence and as of October 2007, Minnesota had
17 operating ethanol facilities with a production
capacity of 675 million gallons per year (10).
3.3.1 Timber
Initially, timber was the main resource that drew
people to Minnesota in the 19th century. With the
Mississippi and St. Croix rivers capable of floating
large amounts of wood to mills in Minneapolis and
Stillwater, the forests were soon clear-cut. By the
1870s the great coniferous forests of the north were
being cut and Minnesota was supplying more timber
to America than was any other state (Borchert 1959).
The vast scale and wealth of Minnesota's timber
resources elevated the social importance of the
lumberjack and generated stories of a mythical hero of
giant proportions, Paul Bunyan and his blue ox, Babe.
Nevertheless, by the 1920s, large-scale logging was
finished in Minnesota and the great forest of the North
Country was called the "cutover" (Borchert 1959).
Beginning in 1895, logging began in the boundary
waters area. At that time, the target resource was
lumber and mine supports for the booming mining
industry in that the northeastern part of the State.
Once all of the big pine had been cut, the industry
shifted to logging for pulpwood. This lasted until 1978
when a state law was passed ending logging in the
Boundary Waters Canoe Area. From 1870 to 1900
Minnesota timber built cities, towns and farms all
across the treeless plains to the south and west as the
prairie lands were settled and developed.
3.3.2 Flour
Flour milling was established to use the
waterpower of St. Anthony's falls to grind wheat,
which was the dominant crop, produced from
Minnesota's rich farmland from the 1850s through the
1880s. Beginning in 1880, and for the next fifty years,
Minneapolis was the largest flour producer in the
United States and second in the world only to
Budapest. Great innovations were made in the wheat
milling industry during this time and Minnesota's
patented spring wheat flour was generally
acknowledged as the best bread-making flour in the
world. The conglomeration of milling companies in
Minneapolis centered on St. Anthony Falls until the
advent of steam and electric power became more
efficient and less expensive to use than water power.
3.3.3 Surface Water
Minnesota has an abundance of surface waters
including over 15,000 lakes, ponds, and wetlands and
several large rivers such as the Mississippi, the
Minnesota and the St. Croix. Minnesota's rivers have
been used for transportation and waterpower since the
1800s and today its lakes are host to many forms of
recreation in all seasons. Lake Itasca, the headwaters
of the Mississippi, is located in Minnesota. The
Boundary Waters Canoe Area (BWCA) lies within the
State and it has been protected since 1978. The
BWCA along with its sister park, Quetico Provincial
Park across the border in Canada and Voyageurs
National Park contain more land area together than
Yellowstone National Park, which is the largest U.S.
National Park. This land contains the largest area of
unlogged virgin forest in the eastern United States.
3.3.4 Iron Ore
Iron was first found in Minnesota as early as 1848;
however, production did not start until 1884. At first,
explorers assumed that all the iron in the State was
low-grade magnetite due to the effect of the rock on
their compasses. However, high-grade hematite was
later found in pockets within the magnetite. There are
three main iron ranges in the State: Vermillion,
Mesabi, and Cuyuna. The Vermillion range no longer
produces ore, but the Mesabi and Cuyuna still produce
two-thirds of the Nation's iron ore. Up to 1980,
Minnesota mines had produced over three billion
metric tons of iron ore. At current rates of production,
Minnesota has over two hundred years worth of
economically retrievable reserves with the potential
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Environmental Accounting Using Emergy: Minnesota
for more if lower grade taconite rock can be
economically beneficiated.
3.3.5 Taconite
Taconite is one of the hardest minerals known,
making it very difficult to mine. Mining of taconite
was not possible until the advent of a drilling
technique known as jet piercing. Recent advances in
mining technology through the use of tungsten-
carbide drill bits, has increased the feasibility of
mining taconite. The process of beneficiating taconite
rock was worked out over many years by E.W. Davis,
a professor at the University of Minnesota, and his
colleagues. To refine the taconite, large plants had to
be built at a price of about 250 million dollars each.
To refine taconite, it must be crushed to a very fine
powder, then, using powerful magnets the magnetite is
separated from undesirable byproducts. Next, the
magnetite is mixed with bentonite clay and fired to
create pellets of hematite that are around 65% iron.
Due to the small size of the pellets, it is easy to mix
them with coke and limestone in a blast furnace to
produce steel. In the furnace, taconite pellets melt
quickly increasing the productivity of the furnace by
roughly doubling the amount of steel that can be
produced in a given time. This increased efficiency
keeps taconite mining competitive with lower cost
sources of ore.
3.3.6 Other Minerals
Recently, a large deposit of copper-nickel ore has
been found in the Duluth Complex in northeastern
Minnesota. This deposit makes up 25% of U.S. copper
reserves and 12% of the world's nickel reserves. In
addition, due to the geology of Minnesota and high
radioactivity of wells, reserves of uranium ore are
thought to exist in the State. Lastly, in 1865 and 1866,
Minnesota had a small gold rush. Since then, however,
no deposits have been found. Exploration continues,
but has yielded nothing but trace amounts of gold and
silver.
3.3.7 Peat
Peat was created in the glacial lakes that covered a
large portion of the State thousands of years ago. It
lies under nearly one million acres within the State.
Peat contains half of the thermal potential of
anthracite coal and may become an important fuel
source in the future.
3.3.8 Agriculture
Minnesota can be divided into four agricultural
zones: the dairy region covering the lake and hill
region in the center of the State, the corn belt on the
rich prairie lands of the southwestern portion of the
State, the cash crop region covering the bed of glacial
Lake Agassiz in the northwestern portion of the State
and the North country, which is primarily forested but
contains a few farms (Borchert 1959). The primary
crops and growing conditions vary across the State.
Corn, soybeans and livestock are the primary crops of
the Corn Belt. Crops like wheat, sugar beets, and
canola that will tolerate colder conditions than corn
are grown on large tracts of land in the cash crop
region. Dairy cattle and corn are grown in the Dairy
Region, which is interspersed with many lakes and
wetlands and includes many small hills where plowing
is difficult, but which are ideally suited for pasture.
The soils in the North Country region are young and
poor in most places and therefore they are not suitable
for large scale agriculture. Agriculture occupies over
40% of the land area of the State and it is one of
Minnesota's largest industries. In 2000, it employed
over 100,000 people and had sales over eight billion
dollars (11). The largest crops are corn, soybeans, and
wheat and the largest livestock sales come from
turkeys, hogs, and cattle. The State is the number one
producer of turkeys in the country.
3.3.9 Education
Minnesotans had an early interest in promoting
education within the State and as a result the State has
become known for its many fine institutions of higher
learning. For example, the University of Minnesota
was founded in 1851 before Minnesota achieved
statehood and it was ranked 20th on a list of the top
research universities the U.S. for 2004 (88). Many of
the early settlers came to Minnesota from the
northeastern United States bringing with them their
knowledge and experience with long-established
schools and colleges. In addition, the State received
many immigrants from northern Europe, who brought
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An Emergy Evaluation of Minnesota
with them a belief in the value of a good education
and hard work. Minnesota has several private schools
that are ranked among the top educational institutions
of the Nation. Minnesota's emphasis on education is
reflected in the knowledge and skill level of the labor
force. This abundance of "know-how" is shown by the
fact that Minnesotans have been innovators in many
fields from flour milling and iron mining to
manufacturing and medicine.
3.4 An Energy Systems Model of Minnesota
An energy systems model of Minnesota that shows
the major economic and environmental forcing
functions, components, and connections is presented
in Fig. 1. It offers a conceptual guide to thinking about
the State and provides the basis for developing
emergy accounts. The environmental energy sources,
as well as the fuels, goods, and services that help
make Minnesota's economy productive, are shown as
circles around the edge of the system boundary, i.e.,
the box labeled "Minnesota, 2000". Purchased imports
and exports generate monetary flows that cross the
State borders in exchange for products and services.
Tourists bring money into the State to spend on
recreation and the Federal government generates both
monetary inflow as outlay and outflows as taxes. The
flows of energy, material, and information into,
through, and out of the State are identified by the
various pathways, each labeled with a subscripted k.
The k's are listed and defined in Table 2, but in this
paper they only identify the various pathways. In a
simulation model, each k has a numerical value that
determines the rate of flow of energy or materials
along the pathway. The system components, e.g.,
economic sectors, shown within the diagram are
defined in Table 3. The external forcing functions for
the State are listed below and they are used in
developing the emergy income statement for
Minnesota. External forcing functions are arranged
around the edge of the box indicating the system's
boundaries from left to right in order of increasing
transformity. In the left hand corner, solar radiation
enters the system followed by other natural energies,
in the form of wind, rain and snow, rivers, and
geologic processes such as uplift, subsidence and
volcanism. Next, the energy of fossil fuel and
minerals enters, followed by material goods and
services, people, and higher social structures, such as
government, markets and tourism.
The model components in Fig. 1 include aggregated
systems for coniferous forests, deciduous forests, and
agriculture, which together represent the natural
production systems in the State. The lakes and rivers,
soils, and ground water of the State are subdivided
into the region in which they are found. In addition,
special systems are assigned within their appropriate
regions, such as "Bogs and Fens", which reside within
the coniferous forest region (Fig. 1). Timber is
distributed between the coniferous and deciduous
forests regions, which would be reflected in the
harvest of softwood and hard wood logs in the State.
The agricultural region is further subdivided into cash
crops and food crops with a storage of soil assigned to
each area. In addition, livestock production is
designated as a separate system. Reserves of
nonrenewable environmental resources are important
to Minnesota. They include iron, sand, gravel
limestone, dolomite, peat, and a recently discovered
large copper and nickel ore body that includes some
platinum. Renewable resources are abundant and also
of primary importance to the economy of the State.
Renewable resources include soil, surface and ground
water, timber and agricultural production. When a
renewable resource is used faster than it is replaced by
natural processes, it makes a nonrenewable emergy
contribution to the State. The mining of nonrenewable
resources supports a large industry to process, upgrade
and ship these raw materials, especially iron to the
steel mills outside the State. Electric power generation
is carried out mostly using fuel and mineral resources
shipped into the State. Agriculture is one of the most
important sectors of Minnesota's economy and, as a
result food processing has become a leading industry
there. Minnesota food processing companies
accounted for 20% of all shipments in 2001 and did
over 30 billion dollars worth of business in 2003 (11).
In addition to food operations, Minnesota is a leader
in manufacturing with prominence nationally and/or
internationally in ethanol and biodiesel, plant
polymers and fibers, paper and packaging, computer
and electronic equipment, industrial equipment,
medical and dental devices, and printing and
publishing.
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Environmental Accounting Using Emergy: Minnesota
w Minnesota, 2000
Figure 1. A detailed energy systems model of Minnesota is shown (see Appendix A for symbol definitions and
Tables 2 and 3 for the definition of sources, components and pathways). The large capital letters
imply connections between sectors without using connecting lines.
26
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An Emergy Evaluation of Minnesota
Table 2. Definition of pathway flows for the systems model of Minnesota's environment and
economy shown in Figure 1.
Pathway Definition of Flow
RO Albedo
RI Wind passing through the State
k0 Solar radiation absorbed by the State
k] Solar radiation absorbed by food crops
k2 Solar radiation absorbed by cash crops
k3 Solar radiation absorbed by deciduous forests
k4 Solar radiation absorbed by lakes and streams
k5 Solar radiation absorbed by coniferous forests
k6 Solar radiation absorbed by bogs and fens
k7 Wind energy absorbed by food crops
ks Wind energy absorbed by cash crops
k9 Wind energy absorbed by deciduous forests
k10 Wind energy absorbed by lakes and streams
kn Wind energy absorbed by coniferous forests
kn Wind energy absorbed by bogs and fens
k13 Rain and snow absorbed by food crops
kM Rain and snow absorbed by cash crops
kis Rain and snow absorbed by deciduous forests
k16 Rain and snow absorbed by lakes and streams
kn Rain and snow absorbed by coniferous forests
kig Rain and snow absorbed by bogs and fens
k19 River water flowing into the State
k20 River water flowing out of the State
k2i Runoff to lakes and rivers from the coniferous forest
k22 Infiltration to ground water in the coniferous forest
k23 Nutrient and water uptake by the coniferous forest
k23' Evapotranspiration by coniferous forest
k25 Ground water supplied to bogs and fens
k26 Evapotranspiration by vegetation in bogs and fens
k27 Runoff to lakes and rivers from bogs and fens
k28 Base flow to lakes and streams in the coniferous forest
k29 Infiltration to ground water from lakes and rivers
k30 Ground water outflow to regions outside the coniferous forest
k31 Evaporation from lakes and rivers in the coniferous forest
k32 Water use by the mining industry
k33 Net production of peat
k34 Net production of coniferous forest biomass
k35 Net production of deciduous forest biomass
k36 Nutrient and water uptake by deciduous forest
k36' Evapotranspiration by deciduous forest
k38 Runoff to lakes and rivers from the deciduous forest
k.39 Infiltration to ground water from lakes and rivers
27
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Environmental Accounting Using Emergy: Minnesota
Table 2 continued
Pathway Definition of Flow
k40 Base flow from ground water to lakes and streams
LH Evaporation from lakes and rivers in the deciduous forest
k42 Water use by power plants
k43 Water use by production manufacturing
k44 Surface water use in food processing
k45 Ground water use in food processing
k46 Ground water outflow to regions outside the deciduous forest
k47 Soft and hard wood timber harvested for manufacturing
k48 Cash crops processed
k49 Livestock processed
k50 Waste produced by livestock
k51 Food crops used as livestock feed
k52 Food crops used in production manufacturing
k53 Cash crops used in production manufacturing
k54 Water and nutrients taken up by food crops
k54 Evapotranspiration by food crops
k56 Ground water used for irrigation of food crops
k57 Waste produced by food crops
k58 Infiltration from food crop soil to ground water
k59 Ground water resupply of soil water
k60 Movement of ground water out of the cash and food crop regions
k6i Water and nutrients taken up by cash crops
k6i Evapotranspiration by cash crops
k63 Runoff to lakes and rivers from cash crop soil
k64 Runoff to lakes and rivers from food crop soil
k65 Surface water used for irrigation of cash crops
k66 Ground water used for irrigation of cash crops
k67 Evaporation from lakes and rivers
k68 Infiltration from lakes and rivers to ground water
k69 Base flow of ground water to lakes and rivers
k70 Waste produced by cash crops
k7i Waste produced by livestock
k72 Geologic processes building landform and mineral deposits
k73 Iron ore mined and processed
k74 Sand and gravel mined and processed
k75 Dolomite and limestone mined and processed
k76 Water used by the mining industry
k77 Electricity used by the mining industry
k78 Fuels used by the mining industry
k79 Goods and services used by the mining industry
k80 Government control of mining
k81 Mining industry inputs to production and manufacturing
k82 Waste produced by mining and processing ores
28
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An Emergy Evaluation of Minnesota
Table 2 continued
Pathway Definition of Flow
k83 Human knowledge and labor used in the mining sector
k84 Transport of fuels into the State
k85 Transport of goods and services into the State
k86 Government regulation of transportation
ks? Human knowledge and labor used in the transportation sector
k88 Electricity used by the transportation sector
k89 Goods and services input to the transportation sector
k 90 Fuels input to the transportation sector
k9i Mining inputs to the transportation sector
k92 Electricity use by the government sector
k93 Fuels input to the government sector
k94 Goods and services input to the government sector
k95 Human knowledge and labor used in the government sector
k96 Federal government regulations
k97 Federal taxes
k98 Federal outlays
k99 Money spent on fuels
kioo Money spent on goods and services
kioi Electricity use by the food processing sector
k102 Fuels input to the power plants
ki03 Goods and services input to power plants
kio4 Government regulation of power plants
k105 Human knowledge and labor used by power plants
kioe Electricity use by education systems
kio? Electricity use by production and manufacturing
k10s Waste produced by power plants (conventional and nuclear)
ki09 Electricity use by service and commerce
ki i o Electricity use by households
kj j j Fuels input to education systems
kn2 Goods and services input to education systems
ki 13 Government regulation of education
k114 Human knowledge and labor used in the schools
kiis Teaching
kn6 Learning
k117 Increase in human knowledge and skills
kiig Loss of information (knowledge and skills)
kn9 Gain of knowledge and skills with immigrants
k120 Loss of knowledge and skills with emigrants
km Government regulation of people
ki22 Goods and services used by people and households
k123 Fuels used by people and households
ki24 Water used by people and households
kns Waste produced by people and households
ki26 Immigration
29
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Environmental Accounting Using Emergy: Minnesota
Table 2 continued
Pathway
Definition of Flow
km
kl28
kl29
kiso
km
k132
kl33
kl34
kl35
kl36
k137
kl38
kl39
kl40
ki4i
kl42
kl43
kl44
kl45
kl46
kl47
kl48
kl49
kiso
kl51
kl52
kl53
kl54
kl55
kl56
kl57
Emigration
Raw and processed ores exported
Manufactured products exported
Raw and processed food exported
Fuels used by production and manufacturing
Goods and services used by production and manufacturing
Government regulation of industry
Human knowledge and labor used in manufacturing
Waste produced by industry
Fuels used by food processing
Goods and services used by food processing
Government regulation of food processing industry
Human knowledge and labor used in food processing
Food processing inputs to manufacturing
Waste produced by food processing
Production and manufacturing inputs to service and commerce
Food processing inputs to service and commerce
Fuels used by service and commerce
Goods and services used by service and commerce
Government regulation of service and commerce
Human knowledge and labor used in service and commerce
Service and commerce used by tourists
Exports from the service and commerce sector
Tourists entering the State
Tourists leaving the State
Money gained from the sale of products and services
Money spent by tourists
Effects of wastes on coniferous
Effects of wastes on deciduous forests
Effects of wastes on agricultural lands
Wastes leaving the State
Minnesotans using recreation and cultural resources
30
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An Emergy Evaluation of Minnesota
Table 3 Definitions of the components for the systems model of Minnesota's environment
and economy shown in Figure 1.
Component Definition
Coniferous Forest
Deciduous Forest
Bogs and Fens
Agriculture
Ground Water
Lakes and Rivers
Soil
Peaty Soils
Timber
Cash Crops
Food Crops
Livestock
Land
Sand and Gravel
Lime stone/Dolomite
Iron
Cu-Ni-Pt
Mining & Processing
Production and Manufacturing
Food Processing
Transportation,
Power Plants
Government
Land covered by coniferous forest.
Land covered by deciduous forests.
Peat forming wetland in the Coniferous Forest region.
Land devoted to food crops, cash crops, or livestock
The quantity of water held in aquifers in the State.
Divided into ground water in the coniferous, deciduous
and agricultural regions.
All surface water in the State including lakes, rivers, and
Lake Superior divided into surface waters in coniferous,
deciduous, and agricultural areas.
The storage of topsoil divided into soil underlying the
coniferous and deciduous forests and cash crop and food
crop agricultural lands.
Peat stored in the bogs and fens.
Tree biomass associated with the coniferous and
deciduous forest lands.
Sugar beets, wheat, rapeseed, etc. generally grown in the
Red River Valley Region.
Corn, Soybeans, etc. usually grown in the southwest and
central regions of the State.
Cattle, hogs, turkeys, etc.
Bedrock and surface materials.
The reserves of sand and gravel within the State.
The reserves of limestone and dolomite.
Reserves of iron ore in Minnesota.
Reserves of copper, nickel, and platinum.
All mining industries in the State including iron ore,
taconite processing, copper, nickel, platinum, sand, gravel,
peat, limestone, and dolomite.
All manufacturing of durable and non-durable goods
including chemicals, pharmaceuticals, plastics, fabricated
and primary metals, and glass, stone and clay products,
Including the industrial use of farm products such as corn
processed to ethanol.
Canning, freezing, meat packing and other processing of
food crops, cash crops, and livestock.
All elements of transportation, including movement by
truck, train, and river.
All fossil fuel, nuclear, and hydroelectric power plants.
State and local government.
31
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Environmental Accounting Using Emergy: Minnesota
Table 3. continued
Component
Definition
Service and Commerce, S
People and Households, P
Education Systems
Know-how
Recreation and Tourism
Waste, W
GSP
Wholesale and retail trade, hotels, restaurants,
banking, real estate, insurance and construction
companies, repair shops; the transportation industry,
communication and utilities; health, legal, social,
personal, and repair services; waste treatment,
hospitals, schools and other government services.
The "S" leaving Service and Commerce connects to
all the other sectors.
The population of Minnesota and their assets
(households).
Primary schools, secondary schools, colleges and
universities.
The knowledge and skill base of the people.
All cultural and recreational activities in the State,
including sports, festivals, canoeing, boating, hiking,
camping, and historical sites.
All solid, liquid, and gaseous waste created by
people, industry, and agriculture and stored in the
State.
Gross State Product
The mix of four nonrenewable energy sources used to
generate electricity is primarily made up of coal,
uranium, and natural gas. The use of wind power is
increasing in the State and some electric power is also
generated from water, oil, and wood. Waste is a by-
product of all human activity and it most significantly
affects the aquatic ecosystems of the State as drainage
from agricultural lands, animal waste, human sewage,
and industrial effluents. The service and commerce
sector supports recreation and tourism, which generates
a significant part of the gross state product, GSP.
People and households in combination with their
knowledge and skills (termed Know-how in the model)
supply the labor that carries out and controls all the
human activities in the State. The state population has
been increasing linearly since 1850, but the rate of
growth has shown signs of slowing during the past few
years (1990-2006). The transportation sector is critical
for the movement of goods and services into, out of, and
within Minnesota. It connects Minnesota to the rest of
the world through an international port at Duluth and
through barge traffic down the Mississippi from the
Twin Cities to New Orleans, LA. Good road and rail
systems complete the linkages for the transport of goods
and services within Minnesota and with Canada to the
north and the contiguous states of Iowa to the south,
North and South Dakota to the west and Wisconsin to
the east.
3.5 The Emergy Income Statement for
Minnesota
The emergy income statement summarizes the major
annual flows of emergy for the State. It consists of four
accounts, renewable resources (Table 4), nonrenewable
resources (Table 5), imports (Table 6), and exports
(Table 7). Each account or table in the emergy income
statement has six columns as defined in Table 1. The
numbers in column one (labeled Note) refer to the
32
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An Emergy Evaluation of Minnesota
listing of calculations and assumptions in Appendix C
that document the values given in column three (Data).
The annual renewable resources and production for
Minnesota in 1997 are shown in Table 4. There is a
corresponding table of renewable natural resources and
products for 2000 in Appendix E, Table El. The wind
energy absorbed is the largest renewable emergy source
received by the State. The chemical potential energy of
rain received by the State is the second largest emergy
source entering the State, followed by the geopotential
energy of rain and snow (the energy of water by virtue
of its elevation relative to sea level). The largest source
of renewable production in Minnesota is crop
production, followed by livestock production, and
timber harvested. The emergy of renewable crops
produced in the State in 1997 was 157% of the emergy
of iron ore mined in that year. The production and use of
nonrenewable resources in Minnesota was evaluated for
1997 in Table 5 with a corresponding evaluation for
2000 in Appendix E, Table E2. Iron ore mined was the
largest emergy from nonrenewable resources produced
in the State followed by sand and gravel and then
dolomite. Petroleum is the second largest nonrenewable
emergy used in the State and it supplies 57% of the
emergy of fossil fuels used, followed by coal (23%), and
natural gas (20%).
In this study we took a small step toward a broader
documentation of environmental liabilities by
quantifying the emergy of some atmospheric pollutants
deposited upon the ecosystems of the State. Nitrogen
and the chloride ion were small compared to the
renewable emergy of the State, 2.7 and 0.6%,
respectively. However, the emergy of sulfur deposited
was 43.7% of the renewable emergy base of the State,
indicating that a substantial environmental liability is
associated with this flow. We determined the
transformity for sulfur using several methods and the
calculations are given in Appendix B.
Minnesota's imports and exports for 1997 are shown
in Tables 6 and 7. There are tables with the 2000
numbers in Appendix E, Tables E3 and E4. The largest
emergy imported to Minnesota in 1997 was in the
materials in goods entering the State. The second largest
emergy inflow was in the services associated with those
goods, followed by the emergy in petroleum. Federal
government outlays may be spent outside the State to
bring emergy into the State; however, these emergy
inflows would be counted in our estimates of imported
goods and services. In addition, Federal outlays will
generate emergy flows in the State economy when they
are spent there. Total outlays must be decreased by the
amount of taxes paid to get the net effect of government
expenditures on the State. If all Federal outlays are used
to buy goods and services outside the State, the emergy
purchased would be slightly more than the emergy
imported in petroleum. However; if they are spent
entirely in Minnesota, the emergy flow generated would
be 1.88 times larger than the emergy imported in
petroleum.
The value and pattern of imports by category in 2000
was similar to that observed in 1997. Differences
between the two years are seen in a 33% decline in the
amount of electricity imported accompanied by an 8.6%
increase in coal emergy imported. Twenty-two percent
of the decline in electricity imports was made up by a
35% increase in electricity from renewable sources.
Natural gas imports increased by 2.3% and petroleum
decreased by 3.3% in 2000 compared to 1997. Other
notable changes are that tourist expenditures in the State
increased by 25% and Federal government outlays by
13% during this time.
The dollars that tourists bring into the State are not
accompanied by emergy per se; however, they generate
flows of emergy in proportion to the State's emergy to
dollar ratio when they are used to purchase products and
services within the state economy. We hypothesize that
the natural, historical, and aesthetic assets of the State
deliver an experience to tourists that can be measured
roughly by the emergy purchased through the dollars
spent on tourism. This approximation gives a
conservative value and the method is similar to the
travel cost method used in economics. A more complete
estimate might be obtained from a detailed analysis of
the emergy required to support the assets that allow
tourists to receive particular experiences. However, this
work would require an evaluation of all aspects of
tourism in the State, which is beyond the scope of this
study. If all 1997 tourist dollars are spent at the
Minnesota emergy to money ratio, they comprise 182%
of the emergy that those dollars could purchase when
spent at an average location in the United States.
Taconite pellets account for the largest amount
(17%) of emergy exported from the State in a single
product. Manufactured value-added products and the
services required to produce them account for 82% of
Minnesota exports. The overall pattern of emergy
33
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Environmental Accounting Using Emergy: Minnesota
exports was similar in 1997 and 2000, primarily because
we relied on the 1997 Commodity Flow Survey (2) for
both estimates. However, there was a 25% increase in
the emergy of the experiences tourists carried home with
them as measured by the expenditure approximation and
a 9.6% increase in Federal taxes between the two years.
3.6 The Emergy Balance Sheet for Minnesota
The emergy balance sheet, when fully developed,
will provide the information needed to determine
whether a human activity, institution, or system is
sustainable (Campbell 2005). The balance sheets given
in Table 8 and Appendix E, Table E5 summarize the
important environmental assets of the State and they
give a rough estimate of the skill and knowledge base of
Minnesota's people. The balance sheet has the same six
columns described for the income statement. The
difference between the income tables and the balance
sheet table is in the units of the items recorded. The
balance sheet contains stored quantities of mass (g),
energy (J), or emergy (sej), etc., whereas, the income
statement contains annual flows of matter (g/y), energy
(J/y), emergy (sej/y) and dollars ($/y).
Separate estimates for natural capital were not
performed for 1997 and 2000 since these assets change
relatively slowly. The social capital in the stored
knowledge of people was determined in 1997 based on
population estimates and using the methods in Odum
(1996). A similar calculation was made for 2000 using
census data. Many of the major storages of natural
capital were estimated, but socioeconomic capital was
not quantified in this study. Storages of natural, social,
and economic capital that need to be evaluated to
complete the balance sheet for this state are as follows:
(1) the emergy in additional stores of natural capital
including biodiversity, (2) the assets of society and
culture, and (3) the economic infrastructure. In addition,
the debts incurred through the loss of natural lands to
urban and agricultural uses and the resulting
diminishment of natural processes over the landscape
need to be quantified and placed on the balance sheet,
respectively, as environmental liabilities and as interest
on the existing environmental debt. Campbell (2005)
presented a theoretical basis for the definition and
measurement of environmental liabilities and the use of
emergy-monetary balance sheets to determine the true
solvency of human endeavors and institutions.
Currently, we are focused on developing the methods to
document environmental liabilities through the
completion of several example balance sheets.
The cumulative extent of the State of Minnesota's
environmental liabilities is unknown; nevertheless, a
partial balance sheet that includes its major natural
capital assets (Table 8) contains useful information that
documents the stored wealth available to the system. In
Minnesota, the emergy of natural capital stored in
accessible iron reserves is the largest actively used
storage of natural wealth followed closely by sand and
gravel aggregate. The large reserves of copper and
nickel ore in Table 8 are in one ore body, which is not
actively exploited at present. This ore body is not as
well-known as the iron reserves, but permits to mine
these resources have been submitted. The iron and
gravel reserves are almost 7 times larger than soil,
which is the third largest actively used storage of natural
capital. The estimate of the amount of sand and gravel in
the State was based on our extrapolation of Minnesota
Department of Natural Resources estimates of the
reserves for the 7 county region around Minneapolis and
St. Paul and other assessed areas in the State. Complete
coverage for the entire state was not available; therefore,
it is more uncertain than the iron reserve estimate. The
emergy in recently discovered reserves of copper and
nickel ore may be, respectively, 11.1 and 2.3 times
greater than the remaining iron reserves, but these
numbers are highly uncertain. The rough estimates for
the quantity of ore for both nickel and copper are the
same, but copper is the richer deposit based on
assessments available to us. Also, a small reserve of
platinum, associated with the copper and nickel ore, is
estimated to be about 0.2% of the mass and 6.7% of the
emergy of the remaining iron ore.
The social capital stored in the education of
Minnesota's people is the tenth largest storage of capital
on the balance sheet. The emergy of the knowledge and
skills of people is slightly less that that stored in peat
and dolomite. This measure of social capital is about 2%
of the emergy in iron ore reserves, but it is almost 700%
of the storage of emergy in forest biomass. The
population of Minnesota has continued to grow in a
linear manner since about 1850, continuously adding to
the knowledge and skills residing within the State.
34
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An Emergy Evaluation of Minnesota
Table 4 Annual Renewable Resources and Production for Minnesota in 1997.
Note* Item
Renewable Resources Within Minnesota
1 Sun, Incident
1 Sun, Absorbed
2 Wind Kinetic Energy
3 Earth Cycle Energy
4 Rain, Chemical Potential Energy Received
5 Evapotranspiration, Chemical Potential
Absorbed
6 Rain, Geo-Potential On Land
6 Snow, Geopotential On Land
7 Rain, Geo-Potential Of Runoff
7 Snow, Geo-Potential Of Runoff
8 Wave Energy (Lake Superior)
9 Rivers Chemical Potential Received
9 Rivers Chemical Potential Absorbed
10 Rivers, Geo-Potential Energy Received
10 Rivers, Geo-Potential Energy Absorbed
1 1 NH4-N In Dry/Wet Deposition
1 1 NO3-N In Dry/Wet Deposition
1 1 Total N In Dry/Wet Deposition
12 S In Dry/Wet Deposition
13 Cl In Dry/Wet Deposition
Renewable Production Within Minnesota
14 Agricultural Products
15 Livestock
16 Fish Production
17 Hydroelectricity And Other Renewable
18 Net Timber Growth
19 Timber Harvest
20 Groundwater, Chemical Potential
21 Solid Waste, Recycled Or Recovered
Data
J, g, $,
ind/yr Units
1.07E+21
8.84E+20
1.26E+19
2.80E+17
7.07E+17
3.14E+17
4.58E+17
7.22E+16
2.55E+16
4.67E+16
1.55E+16
9.15E+15
6.44E+12
5.09E+15
1.51E+15
1.55E+11
4.44E+10
2.00E+11
5.26E+10
8.81E+09
7.00E+17
3.49E+16
1.32E+11
7.95E+15
1.28E+17
6.47E+16
4.61E+15
4.55E+12
J
J
J
J
J
J
J
J
J
J
J
J
J
J
J
g
g
g
g
g
J
J
J
J
J
J
J
g
Emergy/
Unit
sej/unit
1
1.21
1467
33700
18100
28100
10100
101100
27200
101100
30000
50100
50100
27200
27200
1.4E+09
6.8E+09
variable
1.58E+11
1.31E+10
variable
variable
1961800
1.20E+05
20600
68700
159100
6.28E+09
Emergy
E+20 sej
10.7
10.7
185.5
94.3
127.9
88.3
46.2
73
6.9
47.2
4.7
4.6
0.0
1.4
0.4
2.2
3.0
5.2
83.2
1.2
2632.5
584.31
0.003
9.56
26.43
44.47
7.33
286.10
1997
Emdollars
E+6 Em$
419.4
419.4
7244.9
3683.2
4998.0
3449.3
1805.7
2852.4
270.7
1842.8
181.9
179.1
0.1
54.1
16.0
84.1
118.6
202.7
3249.2
45.1
102833.7
22824.5
0.1
548.2
1032.3
1737.2
286.4
140263.4
35
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Environmental Accounting Using Emergy: Minnesota
Table 5. Annual Production and Use of Nonrenewable Resources in 1997.
Note* Item
Data Emergy/
J, g, $, Unit Emergy
ind/yr Units sej/unit E+20 sej
1997
Emdollars
E+6 Em$
Fuels and Renewable Resources Used In A Nonrenewable Manner
22
23
24
25
26
27
28
29
30
31
32
33
* The
Table
Note*
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
Coal Used In The State
Natural Gas Used In The
State
Petroleum Used In The State
Electricity Production
Electricity Used In The State
Nuclear Electricity
Iron Ore Mined
Sand And Gravel
Limestone
Dolomite
Peat
Soil Erosion
notes for Table 5 can be found in
5
3
7
1
2
3
4
3
7
3
2
9
.09E+17
.89E+17
.45E+17
.48E+17
.OOE+17
.89E+16
.79E+13
.45E+13
.35E+12
.08E+12
.90E+10
.79E+16
J
J
J
J
J
J
g
g
g
g
g
J
3.
1.
9.
1.
3.
37800
43500
64800
170400
170400
170400
51E+09
31E+09
81E+08
08E+10
53E+08
72600
192.5
169.4
482.7
251.5
341.3
66.4
1681.1
452.0
72.1
332.1
0.102
71.1
16041.7
14115.8
40228.6
20958.3
28437.9
5530.8
140094.6
37662.5
6008.0
27671.5
8.5
5921.1
Appendix C, Section C.2.
6. Annual Imports to the Minnesota Economy
Item
Tourism (Money Imported)
Electricity
Uranium
Coal
Petroleum
Natural Gas
Minerals
Goods (Materials)
Goods (Services)
Fuels (Services)
Minerals including Uranium
(Services)
Electricity (Services)
Services
Immigration
Federal Government Outlays
(If Spent In US)
Data
J, g, $, md/yr
7.20E+09
4.48E+16
2.94E+09
5.09E+17
7.45E+17
3.89E+17
1.06E+13
3.92E+13
6.63E+10
5.51E+09
1.27E+08
6.22E+08
4.22E+09
8.23E+03
1.98E+10
in 1997.
Units
$
J
g
J
J
J
g
g
$
$
$
$
$
ind.
$
Emergy/
Unit
sej/unit
2.56E+12
1.70E+05
4.66E+11
3.78E+04
6.48E+04
4.35E+04
Variable
Variable
2.56E+12
2.56E+12
2.56E+12
2.56E+12
2.56E+12
variable
2.56E+12
1997
Emer
E+20
184
gy
Emdollars
sej E+6 Em$
.3
76.3
13
192
482
169
106
.7
.5
.7
.4
.0
2747.9
1698
141
3
.0
.0
.3
15.9
108
11
506
.1
.3
.6
7200.
2979.
535
7519.
.0
.5
.5
.5
18857.2
6616.
4142
107338
66326.
5509.
127
621
4221,
441
19789
.8
.5
.1
.8
.2
.0
.7
,5
.0
.3
* The notes for Table 6 can be found in Appendix C, Section C.3.
36
-------
An Emergy Evaluation of Minnesota
Table 7. Annual Exports from the Minnesota Economy in 1997.
Note*
49
50
51
52
53
54
Material
Iron Ore
Services
Services
Item
Goods w/o Iron Ore and Fuels
as Taconite
in Goods
Federal Government (Taxes)
Tourists
(Experiences Taken Home)
J,<
7
3
9.
1.
2.
7.
Data
y, $, ind/yr
.37E+13
.57E+13
.46E+10
.36E+09
.60E+10
.20E+09
Units
g
g
$
$
$
$
Emergy/
Unit Emergy
sej/unit E+20 sej
Variable
3
2
2
2
4
.61E+0
.56E+1
.56E+1
.56E+1
.66E+1
3854
1290
2421.
34.
665
335.
.9
.4
.7
.7
.7
.4
1997
Emdollars
E+6 Em$
150581
50404
94597
1356
26002
13100
.3
.9
.0
.7
.8
.2
* The notes for Table 7 can be found in Appendix C, Section C.4.
Table 8 Assets of Minnesota in 1997.
Note*
55
56
57
58
59
60
61
62
63
64
65
66
67
Item
Forest Biomass Storage
Water (Lakes)
Water (Lake Superior, MN share)
Soils
Iron
Sand & Gravel
Limestone
Dolomite
Copper
Nickel
Peat
Platinum
People
Preschool
School
College Grad
Post-College
Public Status
Legacy
Data
J, g, $, md/yr
6.26E+18
6.76E+17
3.30E+17
9.42E+19
1.40E+16
3.19E+16
2.82E+15
1.32E+14
4.50E+15
4.50E+15
7.57E+19
2.90E+13
4.74E+06
317301
2312528
1812350
246293
47358
765
Units
J
J
J
J
g
g
g
g
g
g
J
g
Ind.
Ind.
Ind.
Ind.
Ind.
Ind.
Ind.
Emergy/
Unit
sej/unit
28200
18100
240300
72600
3.51E+09
1.31E+09
9.81E+08
1.08E+10
1.14E+11
2.55E+10
1.86E+04
1.13E+11
Various
3.34E+16
9.22E+16
2.75E+17
1.28E+18
3.85E+18
7.70E+18
Emergy
E+20 sej
1765.1
122.3
791.8
68375.0
490324.4
417826.0
27661.4
14231.1
5115002.3
1147664.2
14100.0
32728.4
12265.8
105.8
2132.3
4977.8
3165.1
1875.8
58.9
1997
Emdollars
E+6 Em$
68949.7
4778.9
30928.5
2670897.9
19153297.6
16321326.7
1080522.7
555900.5
199804775.6
44830631.0
550780.8
1278454.3
479134.7
4134.1
83294.0
194446.2
123638.3
71321.0
2301.0
* The notes for Table 8 can be found in Appendix C, Section C.5.
37
-------
Environmental Accounting Using Emergy: Minnesota
Finally, relatively small amounts of emergy are stored in
forest biomass and surface waters.
3.7 Overview Models and Flow Summary
Figure 2 shows an aggregated model of the
environment and economy of Minnesota in 1997. It
provides an overview of the emergy and dollar flows
across state boundaries and gives the various natural and
economic sources of the flows. The pathways on the
diagram show the interaction of renewable and
nonrenewable resources within the system and the
exchanges of emergy and dollars that drive the State's
economy. Table 9 identifies the flows of emergy and
dollars shown on Figure 2. The table that summarizes
the flows of emergy and dollars for 2000 is found in
Appendix E, Table E6. The pathway symbols and values
in Table 9 are used in Table 10 to calculate indices. The
number indicated in column one directs the reader to a
description of the calculations used to obtain the
summary flows, which are found in Appendix C6.
,' GSP *-,
i 156 } "
Figure 2: Aggregated diagram of Minnesota's economy and emergy resource base used for the calculation of
indices. Symbols are identified in Table 9. Emergy flows times E+20 sej/y; dollar flows times E+9 $/y.
38
-------
An Emergy Evaluation of Minnesota
Table 9. Summary of Flows for Minnesota in 1997.
Note
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
Letter in
Fig. 2
RA
Ri
N
Ni
No
Ni
N2
F
Fi
F2
G
I
Ii
I2
I3
I4
Is
P2I
P2Ii
P2I2
P2I3
PiI4
Pils
B
E
Ei
E2
E3
E4
P2E
P2Ei
P2E2
P2E3
X
P2
Pi
Item
Renewable Sources Used
Renewable Electricity
Nonrenewable Source Flows
Extracted Fuels and Minerals
Dispersed Rural Source
Cone. Use (Fuels, Minerals, Elec.)
Exported without Full Use
Imported Fuels (Fuels)
Fuels, Minerals Used (F+F2)
In State Minerals Used (Ni'- N2)
Imported Goods (Materials)
Dollars Paid for All Imports
Dollars Paid for Service In Fuels
Dollars Paid for Service In Goods
Dollars Paid for Services
Dollars Spent by Tourists
Federal Transfer Payments
Imported Services, Total
Imported Services in Fuels
Imported Services in Goods
Imported Services
Emergy Purchased by Tourists
Net Emergy Purchased by Fed. $
Exported Products w/o Taconite
Dollars Paid for All Exports
Dollars Paid for Goods
Dollars Paid for Mineral Exports
Dollars Paid for Services
Federal Taxes Paid
Total Exported Services
Exported Services, Goods
Exported Services in Iron
Exported Services
Gross State Product
U.S. Emergy/ $ Ratio 1997 sej/$
MN Emergy/ $ Ratio 1997 sej/$
Emergy
E+20 sej
191
9.6
2608
2537
71
1323
1290
1041
2288
1247
2748
1966
160
1698
108
335
-289
3855
2487
2422
31
35
2.56E+12
4.66E+12
Dollars
E+9 $/y
76.8
6.3
66.3
4.2
7.2
19.8
97.1
94.6
1.2
1.4
26.0
155.9
1997
Emdollars
E+9 Em$/y
7.4
0.4
104.9
2.8
51.7
50.4
40.7
89.4
48.7
107.3
76.8
6.3
66.3
4.2
13.1
-11.3
150.6
97.1
94.6
1.2
1.4
39
-------
Environmental Accounting Using Emergy: Minnesota
E20sej/yr
1041
Fuels and
Minerals
Goods and
Services
Imports
Environment
191
Minnesota
Exports
Goods and Services w/o Iron
6342
1290
Exported Ores and
Concentrates
Figure 3. Summary of Minnesota's environmental and economic emergy flows.
The state system was further simplified using a
"three-armed diagram" (Fig. 3). This diagram gives an
overview of the renewable and nonrenewable emergy
entering and leaving the State. Purchased imports and
exports are shown with a single, simple visual image.
Several key facts can be easily determined from this
diagram: (1) in 1997, exported emergy was 1.33 times
greater than the emergy imported (7632/5755); (2) the
ratio of purchased to renewable environmental emergy
was 30:1 (5755/191); (3) seventeen percent (1290/7632)
of the emergy in exports was derived from the export of
taconite pellets; (4) when the emergy of taconite pellets
is removed from Minnesota exports, the emergy
exported exceeds imported emergy by 10.2%.
3.8 Emergy Indices
Table 10 presents several emergy indices that help us
gain a better understanding of the State of Minnesota in
1997. Similar indices for 2000 are shown in Appendix
E, Table E7. The values of some important indices and
their meaning follow: (1) Twenty-one percent of the
emergy used in the State in 1997 was derived from
home sources, which indicates a low potential for self-
sufficiency compared to other states (see the comparison
of states in Campbell etal. 2005a); (2) The emergy use
per person was 1.53E+17 sej/ind., which shows that
Minnesotans have a high overall standard of living (see
Table 12 and Campbell et al. 2005a); (3) The
import/export emergy ratio shows 1.33 times as much
emergy leaving the State in exports as is received in
imports, which indicates an imbalance in the exchange
of real wealth with the Nation. (4) The emergy used per
square meter (3.23E+12 sej/m2) indicates that an
average location in the State is developed relative to an
average place in the Nation (Table 12); (5) The emergy
to dollar ratio was 4.66 E+12 sej/$, thus the purchasing
power of a dollar in Minnesota in 1997 was 1.82 times
that of an average place in the United States. This ratio
had fallen to 1.69 times the national purchasing power
of a dollar by 2000; (6) The investment ratio was 3.81,
which indicates a relatively low intensity of matching
(Odum 1996) between purchased economic emergy
invested from outside the State and the emergy of
renewable and nonrenewable environmental resources
within the State. This index suggests that Minnesota is
still an attractive place for further economic investment;
(7) The environmental loading ratio was 37.1:1,
indicating a more intense matching of purchased inputs
with renewable energy from the environment than found
for West Virginia (20.4:1) or the Nation as a whole
(19.6:1). Higher environmental loading ratios potentially
result in higher stress on local ecosystems and a heavier
"load" on the waste processing capacity of the
environment.
40
-------
An Emergy Evaluation of Minnesota
3.9 The Emergy Signature for the State
The emergy signature for Minnesota in 1997 is
shown in Fig. 4, which charts the significant emergy
flows within the State as well as the major imports and
exports. The large quantities of iron ore mined in
Minnesota, and the taconite pellets exported indicate the
strength of the connection between Minnesota's
economy and the larger regional economies of the East
coast, the Mid-West, and the world. The large emergy
flows of materials in both exported and imported goods
and services also show Minnesota's role in the larger
system of the Nation and the strength of the State's
economy in agriculture and manufacturing. The second
largest pair of flows is also associated with import and
export. These bars present on the right of the graph
represent the services required for the production and
transport of imported and exported goods. A second tier
of smaller though still important flows includes energy
and mineral, use, import, and export. Social emergy
flows of comparable magnitude to petroleum use are
generated by Federal outlays and expenditures for
tourism. The emergy of Federal government outlays is
fairly large, but once taxes are removed there is a net
outflow of emergy from the State. Petroleum is the
largest component in the energy consumption signature
of the State, but overall the energy use pattern is fairly
well-balanced with substantial inputs from natural gas,
coal, and nuclear electricity balancing petroleum use.
The generation of electricity from renewable sources
was small in 1997, but has grown since then.
3.10 Analysis of Minnesota and Comparison
with other States
The construction of emergy indices from the
accounting data on storages and flows led to insights on
the development and use of the State's natural resources.
A comparison of these results with emergy analyses of
other states and of the Nation will help put the
Minnesota numbers in perspective. In this study, we
compared Minnesota indices to West Virginia indices
and selected national indices; all calculated using similar
methods for documenting imports and exports. Many
emergy analyses of states have been done in the past
(Campbell et al. 2005a) and while the analysis method
has not varied the accuracy with which imports have
been determined has varied. Therefore, the results of
many older analyses are only roughly comparable to
those reported here. Comparisons can be made, but the
investigator should be aware that the estimates of
imported goods and services in older studies may be
somewhat lower than the values that would be expected
using the revised method first presented in Campbell et
al. (2005a). The values of indices that include imported
goods and services in there formulations should be
compared with this caveat in mind.
41
-------
Environmental Accounting Using Emergy: Minnesota
o
? 4500 -,
HI
^- A nnn
X 4UUU
re
2
G> 3000
3
E1
"ii 2000
re
o *| ^nn
| 1000
LL
s>
0) Q
S Exported
H Imported
DPrnrli ifprl
• Renewables
• - . i HI
n H
! n _ 1 • 1 f :l m i— i
g
j
i
P
:
i
i
|
:
i
:
!
(
:
(
i
:
i
!
2
s
j
j
it
i
j
i
i
s
i
!
!
P ! In 1 m K 1
1
^ -y «y <
<
pj£
^? x o° ^* ^% o
\° \*
Category
Figure 4. The emergy signature of the State of Minnesota in 1997 is shown. Items are arranged in order of
increasing emergy per unit. Emergy flows shown to the right of dolomite are determined based on
the emergy to dollar ratio (sej/$) for the U.S. in 1997. Items from solar energy through electricity
imported are arranged by transformity (sej/J) and those from limestone through dolomite are
ordered according to their specific emergy (sej/g).
Table 10. Minnesota Emergy Indicators
Item Name of Index
and Indices for 1997.
Expression
Quantity Units
104 Renewable Use
105 In State Non-Renewable Use
106 Imported Emergy
107 Total Emergy Inflows
108 Total Emergy Used
109 Total Exported Emergy
110 Emergy From Home Sources
111 Imports-Exports
112 Ratio Of Export To Imports
113 Fraction Used, Locally Renewable
114 Fraction Of Use Purchased Outside
115 Fraction Used, Imported Service
116 Fraction Of Use That Is Free
117 Ratio Of Purchased To Free
RA
NO+N!
F+G+P2I
R+F+G+P2I
U=(RA+N0+F1+G+P2I)
B+P2E+N2
(N0+F2+R)/U
(F+G+P2I)-B+P2E+N2)
(B+PjE+Nj)/ F+G+P2I)
R/U
(F+G+P2I)/U
P2I/U
(R+N0)/U
(Fi+G+P2I)/(R+No)
-1
1.91E+22
1.32E+23
5.75E+23
5.95E+23
7.26E+23
7.63E+23
0.21
.E+23
1.33
0.026
0.792
0.271
0.036
26.77
sej y
sej y"
sej y"
sej y"
sej y"
sejy
sej y"
42
-------
An Emergy Evaluation of Minnesota
Table 10 continued. Minnesota Emergy Indicators and Indices for 1997.
Item Name of Index
Expression
Quantity Units
118 Environmental Loading Ratio
119 Inve stment Ratio
120 Use Per Unit Area
121 Use Per Person
122 Renewable Carrying Capacity
123 Developed Carrying Capacity
124 State Economic Product
125 MN Emergy Use To GSP
126 U.S. Emergy Use To GNP
127 Electricity Used/Emergy Use
128 Electricity Produced/Emergy Use
129 Emergy of Fuel Use per Person
130 Population
131 Area
132 Renewable Empower Density
(F1+N0+G+P2I)/R
(F+G+P2I)/(RA+N0+F2)
U/Area
U/Population
(R/U)*Population
8*(R/U)*Population
GSP
U/GSP
U/GNP
El/U
Elp/U
Fuels/Population
RA/Area
37.12
3.81
3.23E+12
1.53E+17
124,235
993,882
1.6E+11
4.66E+12
2.56E+12
0.047
0.035
1.78E+16
4.74E+06
2.25E+11
8.46E+10
sej m"
sej/ind.
people
people
$/yr
sej/$
sej/$
sej/ind.
people
m2
sej m"2
3.10.1 Characteristics of Minnesota Based on Emergy
Analysis
The geopotential energy available in the State of
Minnesota is governed by the fact that most of the State
is covered by landforms that were deposited during the
last glacial period (Tester 1995). The elevation of the
land varies from the lowest point on the Lake Superior
shore (183 m) to the highest point on Eagle Mountain
(701 m). Minnesota is fairly unusual among the states
that we have examined, because the largest emergy
inflow to the State is in the wind energy absorbed, rather
than the chemical potential energy of rainfall. The wind
accounts for more than 97% of the largest emergy base
for the State and waves on Lake Superior make up
2.44% with the remainder supplied by the chemical and
geopotential energy of the St. Croix River that enters
from Wisconsin and flows along the border.
Nonetheless, the renewable emergy supplied by
water is the basis for many ecological processes in the
State, i.e., transpiration of forests and crops, and the
emergy of these flows was also examined. The water
budget of Minnesota is unique among the states that we
have examined in that snow is a prominent feature of the
annual geopotential energy flows. A new transformity
for the geopotential energy of snow was determined in
this study (Appendix B), and based on the global
distribution of rain and snow fall, it was found to be
about an order of magnitude greater than that of the
geopotential energy of rain. In light of this fact, it is
understandable that 32% of the renewable emergy of
water used in the State is supplied by the geopotential
energy of runoff generated by snow. Most of the
remaining emergy of water (59%) is attributed to the
chemical potential energy of rain transpired by
vegetation. The geopotential of rain as runoff, waves on
Lake Superior and the chemical and geopotential of the
St. Croix River make up the remainder. The high
transformity of the geopotential energy of snow relative
to rain means that it should have special organizing
powers not possessed by rainfall, i.e., snow accumulates
over many months and this stored geopotential energy is
released in a pulse over a relatively short period of time
during snowmelt in the spring. This highly concentrated
delivery of geological work that is a property of the
snow pack is consistent with the higher transformity of
snow calculated on the basis of its global annual
production.
Minnesota is richly endowed with mineral resources
(principally iron, but see Table 8). The emergy density
of actively exploited underground fuel and mineral
resources in Minnesota is 4.28E+14 sej m"2. This is
about half of the emergy density of underground mineral
reserves in West Virginia. However, if the vast reserves
of copper and nickel predicted to be available in
Minnesota are proven, the emergy density of minerals
beneath Minnesota would be 3.6 times that of the coal
beneath West Virginia. From this analysis we might
43
-------
Environmental Accounting Using Emergy: Minnesota
predict that iron mining, beneficiation, and transport will
dominate the emergy flows, and ostensibly the
economic activities and environmental impacts in the
northeastern region of the State; however a complete
regional analysis needs to be performed to confirm this
prediction. The emergy of iron produced in Minnesota
in 1997 was equal to 23% of the total emergy used in
the State. Most (75% or more) of the iron mined in
Minnesota is exported (2).
Emergy measures the power to create useful products
and services in a system. The taconite produced in
Minnesota provides a tremendous subsidy (1.29E+23
sej/y) of organizing power to the larger economies of the
United States and the world. However, the actual
subsidy would be 3 times greater, if geological
processes did all the work of concentration. The
transformity of taconite pellets was calculated as part of
this study (Appendix B3.4). This transformity is based
on the work of nature in creating iron ore (taconite rock,
20% Fe) and the energy and human service required to
beneficiate low grade ores. E.W. Davis's technology to
concentrate low grade ores results in a 22:1 emergy
yield for every sej used in beneficiation (Appendix
B3.4). However, when compared to the work that nature
does in creating an ore of 63% iron, the magnification
factor is 47:1. The taconite exported to steel mills in the
east would require three times more emergy, if it was a
natural iron ore with the same iron concentration. This
calculation demonstrates how technology can increase
the production efficiency of materials used by society,
i.e., taconite is like an ore containing 63% iron, which
would take three times as much emergy to produce
through the work of natural geological processes. Given
the high net emergy yield of Minnesota's original rich
iron deposits, it is not surprising that the mining of this
ore during the 1890s led to the rapid expansion of the
iron and steel industry in the United States and
subsequent dominance of the U.S. in manufactured
exports (Irwin 2003).
The emergy to money ratio for Minnesota in 1997
was 4.66E+12 sej/$ compared to 2.56E+12 sej/$ in the
United States as a whole. This index means that in 1997,
the power of a dollar to purchase emergy was 1.82 times
greater at an average place in Minnesota than in an
average place in the Nation. The consequences of this
relationship can be better understood by considering an
example such as Federal outlays and taxes. The United
States contributed $19.8 billion dollars in Federal
outlays to individuals and to state and local governments
in Minnesota in 1997. Multiplying this value by the
emergy to dollar ratio for Minnesota in 1997 shows that
the combined expenditures of the Federal government
could have generated an emergy flow of 9.22E+22 sej/y,
if all the tax money had been spent in the State. This is
71% of the emergy in taconite pellets exported.
However, if the money was spent at an average location
in the United States it would only generate a flow of
5.07E+22 sej (45% less). Federal taxes amounting to
$26 billion were collected from Minnesotans in 1997.
Similarly, if this tax money had been spent in Minnesota
it would have generated an emergy flow that was 1.82
times the flow when spent at an average location in the
U.S. The difference between taxes and outlays in this
year was 6.21 billion dollars or 23.9% of taxes and the
emergy deficit assuming all money was spent in the
Nation was also 23.9%. Table 11 analyzes several
Federal outlay and tax scenarios for Minnesota
depending on where tax dollars and Federal outlays are
spent. As indicated by the relative values of the emergy
to money ratio in Minnesota and the United States, more
emergy flows when Federal dollars are spent in
Minnesota. This fact is balanced by the need for tax
dollars to support national structure and function that all
the states rely upon for their well-being and the well-
being of the Nation.
Emergy parity like monetary parity can be used as a
benchmark to show relative advantage and disadvantage
in a relationship. Scenarios B and C in Table 11,
respectively, show the emergy balance when all Federal
outlays are spent either in an average place in the United
States or in Minnesota. At the same time tax dollars are
removed to support the Nation; and therefore, they
probably are not spent in Minnesota. The results for
Scenario B, in which outlays are spent out-of-state,
show that parity in emergy flows can be obtained by
either increasing outlays or decreasing taxes with a
much larger change in the dollar flow required, if
outlays must be increased rather than taxes cut. Scenario
C, in which outlays are spent in MN, gives the same
result for decreasing taxes that would be found by
seeking monetary parity in the tax-outlay relationship.
However, a larger percentage increase (31% vs. 24%) in
the dollar outlay is required compared to the tax dollar
decrease to achieve both dollar and emdollar parity.
Emergy or dollar parity per se may not result in the
optimum relationship to promote maximum mutual
benefit between a state and the nation of which it is a
part. Energy Systems Theory (Odum 1994) postulates
that maximizing empower at all levels of organization
44
-------
An Emergy Evaluation of Minnesota
Table 11. Analysis of Federal Outlay and Tax Relationships
sejy
.1X1Q20
1997 Em$
% Change
Scenario A (Current)
All Federal outlays spent in MN
All Minnesota taxes spent in US
Surplus for the US
Minnesota surplus over outlays spent in U.S.
Scenario B
All Federal outlays spent in the US
Federal taxes not spent in Minnesota
Emergy Deficit for Minnesota
Emergy Parity
Increase Federal outlays for parity
Decrease Minnesota taxes for parity
Scenario C
Federal outlays spent in Minnesota
Federal taxes not spent in Minnesota
Emergy Deficit for Minnesota
Emergy Parity
Increase Federal outlays for parity
Decrease Minnesota taxes for parity
921.8
665.7
256.1
415.2
506.6
1211.2
-704.6
704.6
921.8
1211.3
-289.4
289.4
3.60E+10
2.60E+10
l.OOE+09
1.62E+10
1.98E+10
4.73E+10
-2.75E+10
2.75E+10
3.59E+10
4.75E+10
-1.13E+10
1.13E+10
1.98E+10
2.60E+10
-6.21E+09
1.98E+10
2.60E+10
-6.21E+09
2.75E+10
1.51E+10
1.98E+10
2.60E+10
-6.21E+09
6.21E+09
6.21E+09
139%
58%
31%
24%
simultaneously (Campbell 2000) is the goal function for
successful systems. The current Federal outlay and tax
situation for Minnesota is shown as Scenario A.
Although we do not know that this scenario is
maximizing empower in both systems, it has some
interesting emergy flow advantages for both the state
and nation. Using the extreme conditions that all Federal
outlays are spent in Minnesota and that all taxes are
spent elsewhere in the Nation, we found that the nation
has an emergy surplus of l.OOE+10 Em$ which is 61%
larger than the monetary surplus ($6.21E+9) under these
conditions. This surplus emergy flow is derived
primarily from the additional empower generated by
spending outlays in Minnesota. In addition, Minnesota
realizes a surplus under these conditions compared to
what it would have if all Federal outlays had been spent
out of the State. Determining the balance of taxes and
outlays between states and the Nation is, of course, a
political decision, but it is apparent that the Federal
government gets good value for its tax dollars spent in
Minnesota. Federal outlays increased 13.1% between
1997 and 2000, while taxes increased 9.6% during this
time (Appendix E). These increases actually result in a
lower Federal stimulus and tax burden for Minnesota,
since the emergy to dollar ratio of the United States
(Appendix B4.2) declined by about 15% over these
years. State emergy flows appear to be more sensitive to
tax decreases, whereas, the Federal surplus may be more
closely tied to an increase in outlays spent in Minnesota.
Spending more of Minnesota's tax dollars to support
Federal functions located in the State or locating new
Federal functions in the State may be win-win situations
for both Minnesota and the Nation.
The largest storage of biological natural capital in the
State is found in Minnesota's soils. The real wealth in
Minnesota soils is 14% of the real wealth in its
remaining iron ore reserves. With this large source of
available energy, it should not be a surprise that
Minnesota was 5th in the Nation in both agricultural
receipts and exports in 2005 (12). We used an emergy
analysis of Florida agricultural crops (Brandt-Williams
2001) as a template to evaluate several Minnesota crops.
The evaluations for Minnesota dairy, spring wheat, grain
45
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Environmental Accounting Using Emergy: Minnesota
corn, and soybeans are reported in Appendix B3.7.2 and
compared to similar crops grown in Florida and
Arkansas (Appendix B3.7.1). The relative difference
between transformities for the same or similar items is a
measure of the relative efficiencies of the two
production processes. Using this indicator we found that
production of the three crops was much more efficient in
Minnesota than in Florida or Arkansas. For grain corn
almost all the inputs were lower and the yield was 3.76
times higher in MN than in FL. The transformity of
grain corn grown in Minnesota was only 0.082 to 0.126
of that grown in Florida with and without services,
respectively. A similar pattern was seen for soybeans for
which yield was 2.32 times higher and most inputs were
lower giving a ratio of transformities (MN/FL) that was
0.28 and 0.42 with and without services. Fertilizer
inputs were markedly less in Minnesota compared to
Florida as might be expected based on Minnesota's
fertile soils. Energy and labor inputs varied by crop and
location, but in general lower amounts of these inputs
were required in Minnesota compared to Florida. One
negative factor was soil erosion which was much greater
in Minnesota. Soil erosion diminishes natural capital
assets and would appear as a credit on the environmental
liability account for agriculture in the State. The
comparison of Minnesota spring wheat to wheat grown
in Arkansas was less favorable. The yield per hectare
was lower (82%), but required inputs were also lower,
especially fertilizer and fuel. This resulted in a ratio of
transformities (0.38 and 0.41) with and without services
that made Minnesota the more efficient producer of
wheat. Dairy production was also more efficient in
Minnesota compared to Florida, but a full analysis of
Minnesota inputs was not available so the exact
difference is not known with confidence.
Since the time of these analyses, Minnesota has
rapidly built up the capacity to exploit its endowment of
renewable emergy and natural capital to meet the State's
and the Nation's need for energy. The use of wind
power in Minnesota increased from 1997 to 2000 and it
has continued to increase up to the present. Renewable
energy production in Minnesota other than from
hydropower doubled from 2000 to 2006 (3) and most of
this was wind power. Even with this increase the
generation of electricity from renewable sources only
accounted for 6.8% of the electric power generated in
Minnesota in 2006. In 2008 the large natural capital
stored in the deep, rich alluvial soils of Minnesota was
not only being used to produce food, but also energy in
the form of corn ethanol. We have seen earlier that
Minnesota is a very efficient producer of corn, but
emergy studies (Odum and Odum 1984, Lanzotti et al.
2000, Ortega et al. 2003, Felix and Tilley 2008) have
shown that ethanol from both agricultural crops and
biomass crops yields little net emergy (Emergy Yield
Ratio, EYR, = 1.1-1.3). The energy sources that were
economic from 1980 until 1994 had an EYR from 3 to
12 (Odum 1996) and in earlier times the Emergy Yield
Ratios were even higher (Odum 1996). Thus, we can not
expect ethanol to replace petroleum as an engine of
growth for the United States, because growth requires a
large net emergy yield. An emergy analysis of the corn
ethanol industry in Minnesota should be performed
evaluating its net emergy yield including any negative
effects on the environment and food production in the
assessment of costs and benefits.
3.10.2 Comparison with other States
Minnesota's status relative to other states and the
Nation can be shown by comparing emergy indicators
and indices. Indices that are related to system
characteristics such as self-sufficiency, sustainability,
and equity in the exchange of real wealth (emergy) are
of particular interest to society because they are related
to the well-being of environmental systems. Table 12
contains comparisons of indices calculated for
Minnesota in 1997 and 2000 with those of West
Virginia in the same two years and for the United States
in 1997. The results reported in Table 12 are calculated
using the same method that incorporated improvements
presented in Campbell et al. (2005a). In addition,
Campbell and Lu (manuscript) have recently
recalculated the emergy to dollar ratio for the U.S. from
1900 to 2004, which allowed us to calculate the partial
set of indices for the United States shown in Table 12.
We will have a stronger basis for comparative analysis
when studies of 6 additional states (VA, MD, PA, DE,
NJ, and RI) for the base years 1997 and 2000 are
completed.
The import/export balance of emergy flows shows
the relationship between trading partners. In a system
where trade is equitable, the emergy exchanged would
be approximately equal, /'. e., there would be parity in
emergy exchange.
46
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An Emergy Evaluation of Minnesota
Table 12. Comparison of Emergy Flows and Indices for Minnesota and West Virginia in 1997 and 2000
with selected indices for the United States in 1997. All flows times 1021 sej y"1 unless otherwise
noted or expressed as ratios.
Index
Renewable Absorbed
In State Non-renewable use
Imported Emergy
Total Emergy Inflows
Total Emergy used
Emergy used from home sources
Exported emergy including fuels
Imports-Exports
Ratio of export to imports
Fraction used, locally renewable
Fraction of use purchased outside
Fraction of use that is imported services
Fraction of use that is free
Ratio of purchased to free
Environmental Loading Ratio
Investment Ratio
Area m2
Population, individuals
Use per unit area, sej m"2 y"1
Use per person, sej ind."1 y"1
Renewable Carrying Capacity,
individuals
Developed Carrying Capacity,
individuals
Gross State Product $
Emergy to Money Ratio sej/$
Ratio of Electricity to Emergy Use
Fuel Use per Person, sej/individual
Renewable Empower Density sej m"2 y"1
Minnesota1
1997
19.1
132
575
595
726
0.21
763
-188
1.33
0.026
0.79
0.27
0.036
26.8
37.1
3.81
2.25E+11
4,735,830
3.23E+12
1.53E+17
124,235
993,884
1.55E+11
4.66E+12
0.047
1.78E+16
8.46E+10
Minnesota1
2000
19.1
146
570
589
735
0.21
759
-189
1.33
0.026
0.78
0.27
0.036
26.7
37.1
3.67
2.25E+11
4,919,479
3.26E+12
1.49E+17
127,574
1,020,589
1.85E+11
3.97E+12
0.047
1.73E+16
8.46E+10
W. Virginia2
1997
6.6
206
159
169
221
0.28
305
-147
1.92
0.030
0.72
0.17
0.031
19.7
20.4
2.39
6.24E+10
1,815,481
3.54E+12
1.22E+17
86,805
694,443
3.83E+10
5.76E+12
0.073
4.50E+16
1.06E+11
W. Virginia2
2000
6.6
196
157
169
230
0.31
288
-129
1.81
0.030
0.68
0.15
0.029
20.6
21.3
2.11
6.24E+10
1,808,344
3.70E+12
1.27E+17
82,702
661,619
3.97E+10
5.79E+12
0.073
3.41E+16
1.06E+11
US1
1997
1031
21240
0.049
0.057
3.5
19.6
9.82E+12
272,912,000
2.16E+12
7.78E+16
13,247,282
108,978,256
8.30E+12
2.56E+12
0.095
1.65E+16
1.04E+11
'This study, ^Campbell etal. 2005).
47
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Environmental Accounting Using Emergy: Minnesota
However, a definitive determination of an equitable
balance between partners would have to consider all
aspects of their relationship, including factors that are
difficult to evaluate such as the exchange of technical
and cultural information and the provision of security.
What is equitable in trade is also determined by the
resource reserves and needs of the various states or
regions and the needs of the Nation of which they are a
part. Often a monetary balance does not mean that the
emergy exchange is balanced and this leads to distinct
advantages in the exchange of real wealth for either the
buyer or seller (Brown 2003, Campbell et al. 2005a).
The Energy Systems approach calls for analysis of
systems on multiple scales to determine the net result of
trade at several different levels of hierarchical
organization, e.g., county, state, nation.
The results in Table 12 show that the emergy of
exports exceeds imports for both Minnesota and West
Virginia. In Minnesota the emergy deficit is caused
primarily by the shipment of iron ores and concentrates
out of the State, whereas in West Virginia the shipment
of coal accounts for almost the entire emergy deficit.
Strategic materials and energy are invariably
concentrated in particular locations in a nation and the
national system could not survive and prosper without
using them broadly. Emergy accounting shows the real
wealth in these resources in terms that are directly
comparable to the real wealth in the purchasing power
of the money received for them. The question that
resource rich states, like West Virginia and Minnesota,
and the Nation must answer is, "What is an equitable
emergy feedback to compensate for the vast quantities
of the work of nature that were required to generate
nonrenewable fuels and minerals?" This question is
complicated by the additional question, "Who owns the
products of nature's work?" and "Who has the right to
benefit from this work?" In the case of Minnesota and
West Virginia the whole nation benefits greatly from the
imbalance in emergy exchange between these two states
and the nation at-large. However, the social
consequences of these deficits have been very different
(IB). Minnesota is one of the richest states in the Nation
(8th in per capita income in 2004), whereas West
Virginia is one of the poorest (48th in per capita income
in 2004). It is interesting that the poorest region of
Minnesota, i.e., the Arrowhead Region, supplies the
Nation with a rich emergy subsidy in ores and timber.
The emergy gain to the Nation from trade with
Minnesota and West Virginia is evidenced by the
emergy exchange ratio (EER) for iron and coal.
Minnesota exported 1290E+20 sej of iron ores and
concentrates in 1997 for which it received 1.2 billion
dollars and West Virginia exported 1497 E+20 sej of
coal in the same year, for which it received 3.92 billion
dollars. The Emergy Exchange Ratios (EER) for
Minnesota iron and West Virginia coal are as follows:
Minnesota Iron;
(1290 E+20 sej/y)/ [($1.2 E+9) (2.56 E+12 sej/$)] =
(1290 E+20 sej/y)/ (30.7 E+20 sej/y) = 42:1
West Virginia Coal;
(1497 E+20 sej/y)/ [($3.92 E+9) (2.56 E+12 sej/$)] =
(1497 E+20 sej/y)/ (100 E+20 sej/y) =15:1
Thus, the buyer of Minnesota iron receives 42 times the
benefit in real wealth compared to the emergy buying
power of the money paid for the concentrates, if the
money paid for the concentrates is then spent at an
average location in the United States. In the case of WV
coal, the net benefit is 15 times the buying power of the
money received. If the money received fortaconite
pellets was spent in Minnesota, the advantage to the
buyer would be 22:1. In either case, Minnesota iron and
West Virginia coal provide large fluxes of real wealth to
support growth in the regional, national and global
economies that receive these raw materials.
The recent increase in oil prices on the international
market provides and example of the limits to growth
imposed when rising prices eliminate the emergy
advantage to the buyer of natural resources. For
example, Saudi Arabian oil at $100 per barrel when
exchanged for 2004 US dollars has an emergy yield of
1.647:1 {(6.1 E+9 joules per barrel) (54000 sej/J)/
[(2.0E+12 sej/$) ($100 per barrel]}. In 2004, $20 per
barrel oil would have yielded 8.2:1 and oil at $164.70
per barrel oil would have no net yield to the United
States. From this preliminary analysis we might guess
that the long term equilibrium price for oil based on
emergy parity of the exchange and the emergy to money
ratio in the U.S. economy in 2004 would be around
$165 per barrel. Above this price the U.S. infrastructure
and functions that depend on oil for their maintenance
would be forced to decline or find substitutes for
petroleum. Of course, the parity price would rise in the
future if the emergy to dollar ratio declines as a result of
inflation, i.e., more dollars and/or less emergy flowing
in the U.S. economy.
48
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An Emergy Evaluation of Minnesota
The empower density or the emergy use per unit area
is indicative of the average intensity of development in a
state. In 1997, the annual emergy use per square meter
in Minnesota was 0.91 of that in West Virginia and 1.5
times that of the U.S. as a whole. Twenty-nine percent
of the State's land area is covered by forests and 39% is
used for agriculture. High empower densities are found
in areas with emergy intensive activities, e.g., iron
mining. Also, major urban areas, such as Minneapolis-
St. Paul, which is a metropolitan regional center with a
diverse manufacturing base, and the port city of Duluth,
which is the center of commerce in the resource rich
northeast. The diverse economic base for Minnesota,
which includes agriculture, mining, manufacturing,
forestry and commerce, illustrates why its emergy flow
density is 50% greater than the Nation as a whole. In the
case of West Virginia, the intense industrial utilization
of coal to generate electrical power for consumption
outside the state and to support chemical manufacturing,
steel production, and other export industries results in
very high empower densities in certain areas within a
state that is 79% forested. This tendency to spatially
concentrate the industrial use of coal power is further
magnified by the relatively small area of flat land in
West Virginia. Thus industry is found to be heavily
concentrated in narrow valleys, as in the Kanawha
Valley and along the Ohio River, and the overall result
is an average empower density 1.64 times that of the
Nation.
The renewable emergy base for a state sets limits on
the level of economic activity that is sustainable without
subsidies from outside. Minnesota can support 2.6% of
the present population at the 1997 standard of living
using its renewable resources alone in their current state
of development compared to 3.0% for West Virginia
and 4.9% forthe Nation. If the 1997 standard of living
in West Virginia is adjusted by removing exported
electricity from total emergy use, 5.8% of the population
could be supported. By this measure, the sustainability
of Minnesota at its 1997 standard of living was 47%
lower than the national average and 55% lower than
West Virginia. Minnesota's large storage of wealth in
iron and mineral reserves will not help its energy
sustainability except through trade for needed fuels.
However, its large endowment of wind energy and
waves and the stored wealth in soils and peat along with
sustainable rotations forthe management of forest
biomass will provide a renewable energy base for
Minnesotans, when fossil fuel energy sources decline.
The investment ratio is an indicator of the
competitiveness of a state in attracting additional
investments. Lower ratios are more attractive for future
development. The investment ratio in Minnesota in 1997
was 3.73:1 compared to an average ratio of 2.39:1 for
West Virginia and 7.0:1 for the United States as a whole
(Odum 1996). In contrast, the environmental loading
ratio. ELR, was 37.3:1, which is 86% higher than West
Virginia (20.4) and the Nation (19.6). This ratio
indicates that economic activities may be putting a large
stress or load on the environment of Minnesota. These
results may mean that the heavy nonpoint loads from
agriculture in Minnesota are at least as important as
intense point loads from mining and chemical
manufacturing found in West Virginia, which of course
are also present in parts of Minnesota.
The fraction of use from home sources for Minnesota
was 0.21 in 1997. West Virginia was less dependent on
the national economy with 28% of its emergy coming
from sources within the State. Since the two numbers
are complements, this fact was also evident from the
fraction of total use that was purchased outside the
State, 0.79, compared to 0.72 for West Virginia.
The emergy use per person is considered to be an
indicator of the overall quality of life experienced by the
people of a nation or state. The emergy use per person
in Minnesota was 25% to 53% higher than in West
Virginia depending on whether exported electricity is
counted in the State's emergy use and 97% higher than
for an average place in the Nation. This index shows
that the quality of life experienced by Minnesotans is
high. This includes not only their economic welfare, but
also the wealth of their natural resources and society. At
present social welfare is captured implicitly in overall
emergy use. In the future we will develop methods to
fully assess the social systems of the State, so that these
values can be captured explicitly in our overall estimates
of welfare.
In 1997, the emergy to dollar ratio for Minnesota
was 81 % of that for West Virginia and 182% that of the
United States. This indicates that in 1997, a dollar spent
in Minnesota purchased about 1.8 times the real wealth
(emergy) in Minnesota products and services compared
to a dollar spent at an average location in the United
States. The emergy to dollar ratio indicates how much
Minnesota loses or gains on average when it trades with
various partners (see the emergy exchange ratio
discussion above). Areas with a high emergy to dollar
49
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Environmental Accounting Using Emergy: Minnesota
ratio can attract tourists and new businesses. The
emergy to dollar ratio of Minnesota indicates that it is an
attractive destination for tourists as indicated by the
increase in tourist dollars spent in the State from 7.2
billion in 1997 to 9 billion in 2000. States with a high
emergy to money ratio, e.g., Maine (Campbell 1998)
and West Virginia (Campbell et al. 2004), often have
tourism as a major part of their economies. The
difference between the emergy to money ratios in West
Virginia and Minnesota indicates that Minnesotans
would gain from vacationing in West Virginia, because
a dollar spent in West Virginia buys more real wealth
(emergy) than it does when spent in Minnesota. This is
true because the free work of the environment
contributes more to local products and services in states
with a high emergy to money ratio. Brown and Ulgiati
(2001) showed that problems can arise when tourists'
dollars compete for limited natural resources in
developing economies. Therefore, where the support
capacity of the system is limited the effects of tourism
on the price of local products consumed by residents
should be carefully monitored.
The ratio of the emergy in the electricity and fuel
used to total emergy use is an indicator of the high
quality energy in people's lives. This indicator of the
standard of living was 36% lower in Minnesota than in
West Virginia and 50% lower than the national average.
We are not sure why Minnesota's use of electricity is a
lower fraction of total use than in West Virginia, but the
emergy of electricity used per capita there is 81% of that
used in West Virginia. This lower electricity use in a
state with a high quality of life might be explained by a
lower fraction of electricity being used for low quality
purposes, e.g., heating, in Minnesota. Fuel use per
person in MN was about the same as in the Nation and
about half of that used in West Virginia, where some
coal mined in-state is used to produce electricity for
export (Campbell et al. 2005a).
3.11 Summary of Findings as Related to the
Management Questions
The findings of the Minnesota emergy evaluation
provide understanding and data to shed light on the
management questions presented above. Here each
question is repeated and then relevant information from
the analysis is presented.
(1) "What is the current level of economic investment in
relation to Minnesota's resource base, and is this level
of investment sustainable?" Minnesota's relatively low
investment ratio 3.81:1 in 1997 and 3.67:1 in 2000 and
relatively high environmental loading ratio (37.1:1)
show that it is a state with enough renewable and
nonrenewable resources to attract further economic
development, while currently experiencing some
degradation of its renewable resource base due to past
and present economic activities. Even though
environmental resources are being exploited by intense
economic development in parts of the State, e.g., the
iron ranges, some agricultural and forest areas, and most
industrial areas, Minnesota's stored wealth is so great
that development pressures can be expected to continue
and increase in the future. The pressure to further
develop Minnesota's resources, as well as current point
and nonpoint pollution produced by agriculture, industry
and mining imply that Minnesota will need to continue
to protect and restore the environment to ensure that the
present high quality of life experienced by Minnesotans
continues into the future.
Our estimate of carrying capacity indicates that only
2.6% of the Minnesota population in 2000 can be
sustained at the 2000 standard of living using the
emergy of renewable resources alone. If the intensity of
resource use needed to support an average developed
state in the world during the 1980s was to be maintained
in the future in Minnesota, only one fifth of the 2000
population could be supported at their 2000 standard of
living. These are conservative levels of support and
technological change to harvest a greater fraction of
renewable emergy inputs for human use may result in
raising these low estimates somewhat. Today,
Minnesotans and the people of the United States as a
whole face serious challenges with regard to our choices
about energy and the environment that will determine
our future prosperity. This fact has become evident to
many people and government and private entities are
beginning to search for solutions.
(2) "What is the net exchange of real wealth (emergy)
between Minnesota and the Nation?" Emergy
accounting shows that Minnesota is a state with great
real wealth in natural resources that supplies a large
emergy subsidy to the Nation. Minnesota exports 33%
more emergy than it receives in return. In 1997, this
resulted in an imbalance of 1.88E+23 sej y"1, which is
about one-fourth of the annual emergy used in the State.
If exported ores and concentrates are removed from the
balance, exports exceed imports by about 10%. In
50
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An Emergy Evaluation of Minnesota
contrast, the monetary exchange between Minnesota and
its trading partners shows a $20 billion surplus in 1997.
The import (+) and export (-) of the emergy in materials
(without considering taconite) is nearly balanced
(-1.7%), but the exported services exceed imported
services by 26.5%. The surplus in value added services
goes directly to the bottom line in its effect on personal
income and the welfare of the population. In contrast,
imported services were slightly larger than exported
services in West Virginia and personal income
apparently suffered as a result. Both states are resource
suppliers for the Nation, exporting large emergy
surpluses in the environmental work used to create fuels
and minerals.
(3) "What are the major causes for any observed
imbalances?" The emergy of iron ores and concentrates
exported without full use accounts for about two-thirds
of the difference between emergy imports and exports in
the State. Most of the remaining imbalance is accounted
for by the work of human services incorporated in
Minnesota agricultural, industrial, and informational
products for export. The large emergy imbalance related
to iron export indicates that the costs and benefits of
iron mining to Minnesota and to the Nation should be
considered as an issue for discussion. For example, one
trade-off is that the economic benefits derived from
taconite used in the steel mills of the mid-west and east
primarily accrue outside of Minnesota, whereas, the
environmental cost of extraction and processing is born
primarily by the State. The environmental damage done
in the State as a result of iron mining was not evaluated
in this study, and it should be addressed in future
research.
(4) "What actions might be taken to address an
imbalance, if it exists?" Federal outlays and taxes are an
obvious way to address trade inequities between a state
and the Nation. The current situation with regard to
taxes and outlays in Minnesota has been explored above.
However, the questions that arise from noting the nature
of the emergy imbalance in trade between Minnesota
and the Nation are more profound than those related to
tax policy. Such questions must consider how we should
count the presently unaccounted for subsidies from
nature's work upon which the existence of all industrial
societies depend. Questions related to the ownership of
these environmental resources arise followed by a
consideration of who should benefit from the millions of
years of environmental work that were required for the
creation of mineral and fossil energy resources. The
heterogeneous distribution of natural wealth and human
occupation of the land raises questions related to the
equity of resource distribution among people, states, and
nations. These questions can not be resolved in this
short report, however, it is apparent that there should be
a national and perhaps a global debate on the
implications of modern society's debt accrued as a result
of its reliance on the renewable and nonrenewable
resources of the environment. This debate and the
questions mentioned above might be elucidated by using
environmental accounting methods and emergy
valuation to systematically consider all the benefits and
costs accruing as consequences of the various policy
choices that arise.
(5) "How does Minnesota's standard of living compare
to other states and the Nation?" The quality of life in
MN as measured by the emergy use per capita is twice
the national average. This index is also high in West
Virginia where it is 1.57 times that of the Nation, but in
this case many social indicators are depressed (CVI
2002). This paradoxical condition can occur if the
benefits of high emergy use are not accurately
transmitted to people by the economic system, but also
see Campbell etal. (2005). Comparison of the situations
in Minnesota and West Virginia revealed that West
Virginia does not maintain a value-added surplus in the
products it provides to the Nation over those it receives.
As a result the emergy that can be purchased with the
dollars West Virginians receive for their work is just
enough to maintain an emergy balance in imported and
exported goods and services but not enough to gain a
comparative advantage in real wealth. The high emergy
use per capita comes in large part from coal mined and
used within the State and much of the emergy value of
this coal is not included in the dollar flows received for
it that people depend on to purchase emergy outside the
State. Thus, in West Virginia there is a paradoxical
situation where the emergy per capita is high but the
quality of life is low. If dollars were flowing into West
Virginia to pay for the uncounted work of nature and if
this money was spent to benefit the people of the State,
West Virginians would have the high quality of life
indicated by their emergy use per capita. In contrast,
Minnesotans use the dollar surplus received for their
value-added manufactured goods compared to imported
goods purchased, to purchase both inside and outside the
State what they need for a high quality life. In this case
the economy is diverse enough so that the imbalance in
real wealth that results from the exchange of iron ore
does not overwhelm the entire economy. This situation
51
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Environmental Accounting Using Emergy: Minnesota
might be different, if regions within the State of
Minnesota were examined.
(6) "Who benefits most from the productive use of the
State's resources?" The 1997 CFS shows that over 53%
of the tonnage of shipments remains within the State.
About 25% of shipments or half of the tonnage exported
goes to the North Central states (OH, MI, IN, WI, and
IL). Louisiana (3.7%), Iowa (3.2%), North Dakota
(3.1%), and Pennsylvania (2.1%) account for another
12% of the tonnage or almost 80% of exports.
Minnesota ships large tonnages (short tons) of
agricultural products (77,391,000), metal ores and
concentrates (47,367,000), gravel, sand, and crushed
stone (45,201,000), and petroleum products
(28,432,000). For the most part, the people of Minnesota
benefit from the productive use of their resources.
Minnesota maintains a favorable trade balance in the
exchange of manufactured products and the skilled work
force commands a premium in the value of exported
goods and services compared to imports. Minnesota's
long history of supporting and promoting education is
undoubtedly a factor in training and maintaining a high
skill level in their population. For example, in 1997 the
average emergy of a person in Minnesota based on their
education level (2.59E+17 sej/ind) was 22% higher than
in West Virginia. Despite Minnesota's favorable
position on the whole, the results of this analysis
indicate that there may be some concern about the
equity of the current terms of trade fortaconite. This
question and other questions related to accurately
accounting for environmental work in the economy
might be examined in more detail as a part of a regional
study of Northern Minnesota.
(7) "How self-sufficient is the State based on its
renewable and nonrenewable resources?" The emergy
indices of self-sufficiency (emergy from home sources)
and dependence (fraction of use purchased outside and
fraction of use that is purchased service) presented
above show Minnesota is dependent on outside sources
for 79% of its emergy use. For West Virginia
dependence on outside sources was only 72% of total
use, primarily because West Virginia coal is used as the
primary energy source for the State. Perhaps more
telling is the fraction of use that is imported services,
which was 27% for Minnesota but only 17% for West
Virginia. All indicators demonstrate that Minnesota is
better integrated with and more dependent on the
economy of the Nation, than is West Virginia. A more
complete understanding of the meaning of this index
and of the other indices in this study will only be gained
as more states are analyzed using these methods and the
results added to the comparison. Minnesota's potential
for self-sufficiency in a lower energy future (Odum and
Odum 2001) may be more accurately shown by the fact
that considerable wind and wave energies are available
to be harnessed on a renewable basis. Also, there is a
large storage of biomass in peat and a smaller but
potentially renewable storage in forest biomass. The
greatest natural biological resource in Minnesota is its
fertile soil (Table 8); therefore, agriculture can be
expected to remain a pillar of the Minnesota economy in
a lower energy world. The large iron, copper, and nickel
deposits in Minnesota may provide the capacity to trade
for the fossil fuels and other items that it lacks far into
the future; however, the considerable environmental
impacts of these activities would need to be mitigated.
The eighth question "How can we manage the
environment and economy to maximize the well-being
of humanity and nature?" relates directly to the
decision-making criteria for environmental managers.
Financial managers have a clear criterion for overseeing
the operations of a business, which is to maximize
profits and shareholder value. Energy Systems Theory
provides a parallel maximal principle related to the
overall well-being of both mankind and nature, which
managers should consider in making decisions on
environmental policy. In this method, policy outcomes
are compared based on the total environmental,
economic, and social emergy flows realized under each
alternative. The maximum power (empower) principle
(Lotka 1922, Odum 1996) indicates that those systems
which maximize empower in their networks will be the
ones that prevail in evolutionary competition among
alternatives. Campbell (2001) gives a theoretical
argument and some practical examples of how
maximizing empower in ecosystems is a mechanism for
determining what is valuable, in the sense that it
promotes system survival and well-being.
Environmental accounting using emergy and energy
systems model simulations allow managers to quantify
the empower relations among environmental systems
with alternative designs. Maximizing empower for the
entire system gives a clear unified criterion for decision
making and provides an answer to the eighth
management question given above. The use of this
criterion in environmental decision-making may help
society avoid the expense of costly trials and errors,
which are often required under present decision-making
paradigms such as adaptive management.
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An Emergy Evaluation of Minnesota
3.12 Recommendations to Managers
Constructing emergy accounts for the State of
Minnesota gave us quantitative and comparable
information to judge the condition of the economy and
environment in the State and to provide preliminary
answers to some management questions. Emergy indices
helped us understand the current condition of the State
and how we might set policies to improve conditions
there. Based on past emergy analyses (Odum 1996,
Campbell et al. 2005a) and the insights gained from this
study, we recommend that the methods and principles of
emergy accounting presented in this report and in Odum
(1996) be used to keep consistent and accurate books for
all human enterprises, including businesses, counties,
states, regions and nations. We recommend that
managers' call for further development of these methods
using the existing and tested methods of bookkeeping
and accounting (Campbell 2005). If emergy accounting
methods continue to be developed and tested so that
they become generally accepted, managers will be able
to use independent emergy audits of their
environmental, economic, and social systems as a
regular part of a system of checks and balances
governing the relationship between economies, societies
and the environment.
3.13 Minnesota and the Future
No system on earth exists alone. According to the
maximum empower principle (Lotka 1922, Odum
1996), they all have developed interactions with the net
result that empower (emergy per unit time) moves
toward a maximum under a given set of external forcing
energies (emergy signature). The maximum empower
principle implies that human and natural systems will
become coupled in ways that increase emergy flow.
Therefore, we can expect Minnesota to follow this path
in the future constrained by the changing emergy
signature of the Earth. Present Minnesota connections
include sediments, nutrients that move from this north
central state to the Louisiana coast via the Mississippi
River and cargo that is transported to and from
Minnesota on the river. Also, goods from Minnesota and
the hinterland states to the west, e.g., the Dakotas and
Montana, are shipped to the Atlantic Ocean through the
Port of Duluth via the Great Lakes and the St. Lawrence
Seaway and other goods are returned to the hinterlands
via this route. Railways and highways carry Minnesota
exports and imports coupling the State's economy most
closely with the surrounding states of the North Central
Region and Canada, but also to a lesser degree with
states throughout the Nation as shown by data form the
CFS (2). Energies of many kinds are exchanged within
and among these state systems and both the state and
national systems should be better off in the long run as a
result of this process. However, when the external
emergy sources to a system are changing, it often takes
some time for emergy flows to be maximized under the
new or changing conditions (Campbell 2000b). If
maximizing empower in a system network is the
decision criteria in evolutionary competition as
proposed by Lotka (1922) and Odum 1996), then
emergy analysis can help discern where the patterns of
interaction may be improved (by elucidating conditions
that increase emergy flow) toward the end of attaining
greater benefits (empower) for the environmental
system as a whole including all its ecological, economic,
and social components.
In the future if not now, world oil production will
reach its peak and then decline (Campbell and Laherrere
1998) and the United States will become more
dependent on the remaining deposits of fossil fuels
within its borders and on the renewable energies that
flow into it each year. West Virginia coal and Minnesota
iron, copper and nickel will be important nonrenewable
resources for the Nation in the future. Since
nonrenewable resource supplies of energy and materials
are limited, it is now and will continue to be important
to continuously restructure societal systems to fit the
global resource base. Minnesota can prepare for the
challenge of meeting larger demands on its natural
resources by using its education system to carry-out
needed research on energy and the environment. In
addition, emergy accounting methods may be widely
taught and used to evaluate the environmental and
socio-economic costs and benefits associated with
current economic production systems, energy
technologies, and development plans. Such analyses will
help determine what alternative system designs lead to
social and economic prosperity and which ones will
maintain a healthy environment and be sustainable, i.e.,
supported by the capacities of the existing emergy
signature. The emergy accounts and indices presented
above are a beginning to help Minnesota move toward a
prosperous and sustainable future.
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Environmental Accounting Using Emergy: Minnesota
Section 4
Discussion
The publication of "Environmental Accounting:
Emergy and Environmental Decision Making" by H.T.
Odum in 1996 made the methods of Emergy Analysis
easily available to the broader scientific community for
the first time. These methods make it possible to keep
"the accounting books" for an environmental system,
including accounts for the economic, ecological, and
social components of these systems, in common units of
solar emjoules (sejs). Despite the promise that some
scientists see in emergy methods, the scientific
community as a whole has been slow to recognize this
potential. Tests of the method and comparison of results
to other methods have been infrequent; and therefore,
the potential benefits of adding emergy accounting to
the tools commonly used by environmental managers
have been foregone. One purpose of this series of
technical reports (Campbell et al. 2005a) is to make
emergy methods and data sources easily accessible to
ecologists, economists, and managers within and outside
the EPA in a peer reviewed government document, so
that they might be more widely tested and applied in
finding solutions for practical problems encountered in
managing the complex systems of humanity and nature.
A second purpose was to present the results of an
emergy evaluation of Minnesota and to test the efficacy
of these methods by addressing questions that
environmental managers have about economic and
environmental conditions and policies relevant to
managing a whole state.
The methods of emergy accounting are still
developing, but we believe that they possess great
potential as a tool to aid environmental decision-
making. Several advances in the method have been
incorporated into this series of reports: (1) we made the
analogy between emergy accounting and financial
accounting and bookkeeping explicit by proposing the
use of emergy income statements and balance sheets as
the standard tools of environmental accounting
(Campbell 2005, Campbell et al. 2004). (2) We found
formerly unused data sources and revised the method for
evaluating imports and exports to and from states in the
United States, making it possible to construct accurate
accounts for these important fluxes. (3) We calculated
new transformities for snow, taconite, dolomite, sulfur,
and the chloride ion (Appendix B), and estimated rough
transformities for commodity classes in the Standard
Classification of Transported Goods (SCTG). In
Appendix B we also included revised calculations of the
emergy and transformity of agricultural products using
updated numbers for the emergy to dollar ratio and for
the transformity of evapotranspiration. Three Minnesota
crops and milk production were also analyzed. The new
transformities section includes an update of the
calculation of the transformity of electricity generated
from nuclear power first presented in Campbell et al.
(2005). The transformities of minerals used in this report
reflect the new method proposed by Cohen et al. (2007).
This method is not perfect and it may be adjusted in the
future, but we believe that it gives more accurate
estimates of the emergy required to produce
economically viable concentrations of the elements than
those found by methods currently in use. To apply this
method, the emergy of a mineral deposit needs to be
adjusted by taking into account its ore grade.
4.1 Standard Methods versus Intellectual
Creativity
The methods of emergy analysis have evolved over
the past 37 years (Odum 1971, 1983, 1996) and the
vitality and creativity of new insights and ideas have
played an important role by creating the present
generality and flexibility of the method. This has caused
the accuracy with which the various flows have been
determined to vary over time. For example, previous
emergy analyses for the states of Florida (Odum, et al.
1986, Odum et al. 1998b), Texas (Odum, et al. 1987),
Alaska (Brown et al. 1993), North Carolina (Tilley
1999), Arkansas (Odum et al. 1998a), and Maine
(Campbell 1998) have each added new insights and
ideas to the method for analyzing states, but differences
in the quantification of inputs make the results of these
analyses, done over many years, only good for first
order comparisons. Comparisons are still possible
54
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Discussion
because emergy analyses report relative results and thus
the conclusions of a study rarely change unless there are
large changes in the inputs. It is not our intent to limit
the future development of emergy analysis methods;
however, standards for the emergy analysis of states and
other systems are needed to make results comparable
and to ensure that anyone can use the proposed tools to
reproduce results. We hope that the material presented
here makes the method for constructing the emergy
accounts for states transparent and reproducible to all
those who choose to use and improve it. To this end we
included extensive notes in the appendices that
document the calculations of the entries on the emergy
tables. Appendix D is devoted to a detailed description
of the method that Campbell et al. (2005a) used to
determine the emergy of imports and exports. We also
include Appendix B that documents the sources for all
the transformities used and the calculations for the new
transformities that were determined in this study.
4.2 Methods Developed and Refined in this
Study
The renewable emergy base for a system is an
important characteristic that has been determined using
various rules over the years. The objective in calculating
this quantity is to determine the degree to which the
renewable energy sources of the earth have been
concentrated in a particular area without double
counting any of the inputs. The renewable emergy
delivered to the system boundaries is received by the
system. The part of the renewable emergy received that
is absorbed is most important because it is the emergy
actually used within the system to make products and
services. The mutually supporting role of the various
kinds of energy transformed in the system has been
clearly demonstrated by the complementary interactions
of the geopotential energy of runoff and the chemical
potential energy of evapotranspiration working together
to structure landscapes (Romitelli 1997, Odum et al.
1998a, Brandt-Williams 1999). In this study, the
renewable emergy received (RR) and the renewable
emergy absorbed (RA) were clearly distinguished in
definitions and in the calculation of indices. We think
that it is important to distinguish these two quantities
because the transformity of the system and its products
are a direct consequence of the energy used in that
system, whereas, the energy received by the system
indicates the potential of the system for development.
That is, the amount of emergy received may determine
the attractiveness of an area for investment and future
development. For example, all the river water entering a
state could be used to support economic activities within
that state, but invariably only a small portion will be
used. If the boundaries are wide enough, almost all the
emergy received can be used in the system,
nevertheless, we believe that these two quantities should
be distinguished in future calculations of emergy indices
that use the renewable emergy base for the system. For
Minnesota this distinction was not very important,
because wind energy was the largest renewable input to
the State and its calculation is only for what is absorbed.
Similarly the second largest input was from waves and
this calculation also is only what is absorbed. Water
more often has chemical and geopotential energies that
enter and then leave a region with only a part of the
delivered available energy absorbed by the system. In
this case, only the St. Croix River contributes to the
emergy base of the State and its contribution is less than
1% of the total.
The method for calculating the imports and exports
to and from a state in the United States was revised to
use data from the U.S. Census Bureau's Commodity
Flow Survey for 1997 (this survey was updated in 2002
but this data was not available at the time this study was
performed). This revised method and new data sources
represented a major improvement in accuracy over the
first method used to determine the imports and exports
to and from the State's economy (Campbell et al.
2005a). In this study, we further revised this method and
used new calculations of the emergy base for the United
States to put the national indices on the same basis as
those calculated for the states. To reconcile all studies
West Virginia was updated to use the new number for
the emergy to money ratio of the United States in 1997
and 2000 (Campbell and Lu, manuscript).
4.3 Quality Assurance: Reliability of the Data
and Uncertainty
One question that should be asked of any scientific
analysis is, "How do we know that the results reported
are correct and accurate?" This question is particularly
relevant for extensive and/or complex analyses that
draw upon many sources of data. In common usage, the
word "uncertain" means that something is unknown or
doubtful; however, in scientific language "uncertainty"
pertains to the probability structure of the data. For,
example, a relevant variable such as rainfall can be
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Environmental Accounting Using Emergy: Minnesota
expressed as the mean of a normal distribution plus or
minus its standard deviation. Reporting the probability
structure of the data always provides more information
and may in some cases (e.g. risk analysis) allow better
decisions to be made. However, the time and effort
required to obtain probability distributions for all data in
an extensive analysis may not be worth it, if the
variation is small or for some other reason not
important. In emergy analysis there is often a great
diversity in the amount and kind of information
available on the various numbers used in the analysis.
For this reason, emergy accounting provides 1st order
answers to questions on the scale of the analysis. If more
exact answers are needed to particular questions, the
scale of the analysis can be reduced by using a smaller
window in space and time to set the system boundaries.
As a rule of thumb, emergy analysts aim to achieve
estimates that are within 10-15% of the actual value of
the variable used in the analysis. Some numbers will be
determined with a higher degree of accuracy, but others
may be less accurate. Because many systems are
characterized by dominant energy flows that exceed the
less important flows by an order of magnitude or more,
a first order estimate of quantities is usually sufficient to
produce a robust analysis. Many emergy analyses have
been performed over the past 20 years and numerous
errors have been found and corrected in these analyses,
but the results of an emergy analysis are rarely changed
by subsequent corrections.
For example, during the development of the West
Virginia emergy evaluation process many errors were
found and corrected and the methodology was
improved. Additional improvements have been made in
the process of evaluating Minnesota. The history of
changes in values and indices in these reports is used to
illustrate the sensitivity of emergy analysis to error
correction and improvements in methodology (e.g.,
model uncertainty). In addition, the relevant
characteristics of the different types of data are reported
and an explanation of the techniques used to check and
ensure the accuracy of the numbers used in this analysis
is given.
Two sources of uncertainty are considered (1)
uncertainty in the numerical values of the quantities
used and (2) uncertainty in the methods and models used
to make determinations. Uncertainty in the numerical
values arises from imprecision of the measuring device,
scanty or unrepresentative data, and systematic flaws in
the measuring process (Finkel 1990). Model uncertainty
arises from difficulties in determining which quantities
are relevant to the analysis, from the technical methods
used to determine those quantities, and from the choice
of surrogates when the needed information is not
directly available.
Both environmental and economic data are key
inputs to emergy analyses. The broad data quality
objective for these data is that values be determined to
within 10-15% of the actual value with a high degree of
confidence. Environmental data is generally determined
to within 10-15% and meets our data quality objectives
(Campbell 2003a). For example, pyroheliometers
measure incident solar radiation with 2-5% accuracy,
anemometers measure wind speed within about 5% and
rain gauges record precipitation within about 10%, but
newer electronic instruments claim ±3% accuracy.
The Energy Information Administration (EIA)
provided key data on energy production, consumption
and movements. The EIA obtains data from survey
forms, some of which are statistical samples, as well as
from many additional information sources (14). They
report both sampling and non-sampling errors in their
surveys, and have extensive procedures in place to
guarantee data quality. In some cases, almost all
participants in a process are counted. In 1997, for
example, EIA documented 1,850 coal producers who
reported production, which included all U.S. coal
mining companies with production of 10,000 short tons
per year or more. Thus, almost all coal production in the
U.S. is counted in the EIA estimate and therefore in
most cases, EIA data would fall within our data quality
objective of 10-15% accuracy.
Commodity Flow Survey (CFS) data was critical in
the development of a revised method for calculating the
import and export of emergy to and from a state. The
CFS is a survey conducted every five years by the U.S.
Census Bureau. Both sampling and non-sampling errors
are considered, and the reliability of the data is reported
as the coefficient of variation with its standard error (2).
The CFS data meets or exceeds our data quality
objectives for total commodity movements. For
example, the total dollar value of inbound shipments to
Minnesota was determined within 3.1% and the tonnage
value within 6.7%, whereas, the dollar value of
shipments leaving the State was determined within 4.3%
and tonnage leaving within 8.9%. Some of the estimated
movements of individual commodities have higher
uncertainties, which exceed our 10-15% criteria. Major
56
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Discussion
energy or mineral flows are checked using EIA and
USGS data as well as data from the CFS. In summary,
we have a high degree of confidence that the material,
energy, and monetary flows upon which the energy and
emergy calculations of bulk imports and exports depend
have been determined within 10 - 15% of their actual
values.
The effect of the propagation of errors in the
estimation of emergy can be estimated as follows. In
general emergy is the product of two independent
numbers the estimate of the available energy or exergy
and the estimate of transformity. If we assume that the
data quantity objectives specify that these two numbers
be estimated to within ± 10% of the actual value, the
propagation of error for two independent variables
multiplied together would increase the error of the
estimates from ± 10% to ± 14.1% (89).
Whenever the opportunity has arisen, we have used
duplicate data and different calculation methods to
check the accuracy of estimates. For example, the EIA
information on coal imports and exports was used to
check the CFS estimates of these quantities. Petroleum
imports from the CFS were checked against the
petroleum imports that were required to meet the
difference between in-state production and consumption
obtained from the EIA data. Potential temporal
anomalies in the economic data were assessed through
collecting and comparing socioeconomic data for two
years. Long term averages (10-50 years) were used for
environmental variables. In this case, the variation is not
reported because most socioeconomic systems depend
on the long term average environmental conditions for
support and development. Trends or variations in the
long term data would be considered as a part of a
dynamic energy systems model analysis of the State (not
performed in this study). The effect of our
improvements in the methodology for estimating
imports and exports was discussed in Campbell et al.
(2005). In general, everything that is known to be of
importance in the system under analysis is included. The
emergy associated with each item is an indicator of its
relative importance and determines whether an item is
included in the analysis.
The effect of correcting an error in the determination
of the energy associated with an input is illustrated by
the recalculation of the geopotential energy of runoff
absorbed by the West Virginia system. In Campbell et
al. (2004), this number was incorrectly calculated,
because the energy used was determined relative to sea
level rather than the minimum elevation of rivers
leaving the State. When this number was corrected, the
energy absorbed changed from 6.59 E+16 J/y to 6.02
E+16 J/y, a difference of 8.6%. This resulted in a
change of 2 E+20 sej/y or 2.9% in the emergy absorbed
by the system and a change of 0.0008 or 2.9% in the
fraction of use that is locally renewable, which is an
important index calculated using the renewable emergy
absorbed. Other calculations that have been refined have
resulted in a similar or smaller percentage change in the
energy, emergy, and emdollar values. Even the large
change in the ratio of imports to exports was based on a
30% decrease in the difference between emergy
imported and emergy exported. The major conclusion
that West Virginia was a net exporter of emergy was
unchanged by methodological improvements and the
correction of errors in calculations.
A second example showing the effect of model
uncertainty in determining the emergy associated with
an input can be seen in the evaluation of the
transformity of electricity from nuclear power which
appears in this study and in Campbell et al. (2005).
Cohen et al. (2007) was used to determine the
transformity of elemental uranium adjusting it using the
ore grade of uranium mined in the United States. The
former method had used the determination of the
transformity of uranium ore from Odum (1996) to
estimate the emergy of the uranium used in generating
nuclear electricity. The calculation using the mass of
uranium oxide, U3O8, to estimate the emergy of uranium
required was 45% of the original estimate based on the
ore required. This resulted in the transformity of
electricity generated from nuclear power declining from
51,900 sej/J to 48,100 sej/J or 7.3%. The conclusion that
nuclear power is one of the most efficient processes for
generating electricity was reinforced by these
calculations, e.g., electricity from coal requires 162,000
sej/J, (Odum 1996).
The transformities and specific emergies by which
the energy or mass flows are multiplied, respectively, to
obtain emergy are critical numbers in the analysis.
Campbell (2003) analyzed five global water budgets,
and determined that the transformities of global
hydrological flows, such as rain, evapotranspiration, and
river flow, were determined within an average standard
deviation of 5.9± 2.5% of the mean value of the 5
estimates. These global transformities meet our data
quality criteria for emergy analysis. Multiple
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Environmental Accounting Using Emergy: Minnesota
determinations of transformities are not often available,
and an accurate estimate of the differences that arise
from different sources of data and different estimation
techniques is not available for most items. In a few
cases, multiple determinations of transformities using
different methods have been carried out. Odum (1996)
determined the transformity of coal from its relative
efficiency in producing electricity and from its
geological production process. The former method gave
an estimate of 4.3E+4 sej/J and the latter 3.4 E+4 sej/J.
The two values are within 12 % of the mean value,
which may be a rough estimate of the model uncertainty
in determining transformities. In a similar example,
Bastianoni et al. (2005) estimated the transformity of
petroleum from its geological process of formation and
found it to be 55,400 sej/J compared to 53,000 sej/J
determined by Odum (1996) by the method of relative
efficiencies. These two estimates are within 2.5% of the
mean value.
We estimated the transformity for each SGTG
commodity class to determine the emergy in the tonnage
of each commodity imported. These transformities are
approximated by averaging known transformities of
items within the class (without services); however, all
items in a class are not included in the determination of
the transformity. In some cases, when a transformity
was not known for an item in a class, the parent material
was used as a surrogate for the item's transformity. The
use of parent materials results in a minimum estimate of
the emergy imported and exported in these commodity
classes. For example, we updated the transformity for
goods in which steel is the major component by using
the new transformity for iron determined in this study
(Cohen et al. 2007). More work is needed to calculate
additional transformities and to obtain better estimates
for known transformities using detailed production
processes, multiple data sets and different calculation
methods to determine the distribution of values.
4.4 Future Research and Reports
The methods described in this report represent a
significant step forward in our ability to perform
accurate and comparable emergy analyses of states
within the United States. Comparable state analyses
provide the raw material for the analysis of regions,
which is of particular concern to the USEPA and other
government agencies that are responsible for the
management of environmental, social, and economic
conditions within regional areas, e.g. EPA Region 3, the
Mid-Atlantic Highlands, The Chesapeake Bay
watershed. There are emergy analyses for eight
additional states in various stages of completion as this
report is being written. The five states of the Mid-
Atlantic region (WV, VA, PA, MD, and DE) are among
the eight states analyzed and an emergy analysis of this
region is planned in the future. In addition, the emergy
accounts for the nine states (MN, WV, MD, VA, PA,
NJ, DE, RI, CO) are in progress and when completed
will allow a robust comparative analysis of emergy
indices. Our current research is focused on the
development of methods to evaluate environmental
liabilities, which are needed to complete the emergy
balance sheet for any enterprise, e.g., nation, state,
county, business, or institution. Once this work is
complete, we will have an accounting method to
determine directly whether any human endeavor is
sustainable.
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Section 5
References
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Environmental Engineering Sciences, University of
Florida, Gainesville, FL.
Brown, M.T. and Ulgiati, S. 2001. Emergy measures of
carrying capacity to evaluate economic investments,
Population and Environment 22, 471-501.
Brown, M.T., Woithe, R.D., Odum, H.T., Montague,
C.L., Odum, E.G. 1993. Emergy
Analysis Perspectives on the Exxon Valdez Oil Spill in
Prince William Sound, Alaska. Report to the Cousteau
Society, Center for Wetlands and Water Resources,
CWWR 93-1, University of Florida, Gainesville.
Buranakarn, V. 1998. Evaluation of Recycling and
Reuse of Building Materials Using the Emergy
Analysis Method. PhD. Dissertation, University of
Florida, UMI Dissertation Services, Ann Arbor MI,
257 p.
Campbell, C.J., Laherrere, J.H. 1998. The End of Cheap
Oil. Scientific American (March): 78-83.
Campbell, D.E. 1998. Emergy Analysis of Human
Carrying Capacity and Regional Sustainability: An
Example Using the State of Maine. Environmental
Monitoring and Assessment 51:531-569.
59
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Environmental Accounting Using Emergy: Minnesota
Campbell, D E., 2000a. A revised solar transformity for
tidal energy received by the earth and dissipated
globally: Implications for Emergy Analysis, pp.
255-264. Brown, M.T., Brandt-Williams, S.L., Tilley,
D.R., Ulgiati, S. (eds) Emergy Synthesis: Theory and
Applications of the Emergy Methodology.
Proceedings of the 1st Biennial Emergy Analysis
Research Conference, Center for Environmental
Policy, Department of environmental Engineering
Sciences, University of Florida, Gainesville, FL.
Campbell, D.E. 2000b. Using energy systems theory to
define, measure, and interpret ecological integrity and
ecosystem health. Ecosystem Health 6(3): 181-204.
Campbell, D.E., 2001.Proposal for including what is
valuable to ecosystems in environmental assessments.
Environ. Sci. Technol. 35: 2867-2873.
Campbell, D.E. 2003a. A Note on the Uncertainty in
Estimates of Transformities Based on Global Water
Budgets, pp. 349-353. In Brown, M.T., Odum, H.T.,
Tilley, D.R., Ulgiati, S. (eds.) Emergy Synthesis 2.
Proceedings of the Second Biennial Emergy Analysis
Conference. Center for Environmental Policy,
University of Florida, Gainesville.
Campbell, D.E. 2003b. Emergy Analysis of the
prehistoric global nitrogen cycle, pp. 221-239. In
Brown, M.T., Odum, H.T., Tilley, D.R., Ulgiati, S.
(eds.) Emergy Synthesis 2. Proceedings of the Second
Biennial Emergy Analysis Conference. Center for
Environmental Policy, University of Florida,
Gainesville.
Campbell, D.E., 2005. Financial Accounting Methods to
Further Develop and Communicate Environmental
Accounting Using Emergy, pp. 185-198. In Brown,
M.T., In Brown, M.T., Bardi, E. Campbell, D.E.,
Comar, V., Huang, S.L. Rydberg, T., Tilley, D.R,
Ulgiati, S. (eds). Emergy Synthesis 3. Proceedings of
the Third Biennial Emergy Analysis Conference,
Center for Environmental Policy, University of
Florida, Gainesville.
Campbell, D.E., Odum, H.T. 1998. Appendix B -
Calculation of a revised solar transformity for tidal
energy received and tidal energy dissipated globally,
p. 566. In: Campbell, D.E., Emergy Analysis of
Human Carrying Capacity and Regional
Sustainability: An Example Using the State of Maine.
Environmental Monitoring and Assessment 51:
531-569.
Campbell, D.E., Lu. H.F. (manuscript). Historical
Evaluation and Analysis of the Emergy to Money
Ratio for the U.S. and China. In: Brown, MT et al.
(eds) Proceedings of the 5th Emergy Research
Conference, January 31-February 2, 2008, University
of Florida, Gainesville FL.
Campbell, D., Meisch, M., DeMoss, T., Pomponio, J.,
Bradley, P. 2004. Keeping the books for the
environment: An emergy analysis of Minnesota.
Environmental Monitoring and Assessment 94:
217-230.
Campbell, D.E., Brandt-Williams, S.L., Meisch, M.E.A.
2005a. Environmental Accounting Using Emergy:
Evaluation of the State of West Virginia. USEPA
Research Report, EPA/600/R-05/006.
Campbell, D.E., Brandt-Williams, S.L., Cai, T.T. 2005b.
Current Technical Problems in Emergy Analysis, pp.
143-157. In Brown, M.T., In Brown, M.T., Bardi, E.
Campbell, D.E., Comar, V., Huang, S.L. Rydberg, T.,
Tilley, D.R., Ulgiati, S. (eds). Emergy Synthesis 3.
Proceedings of the Third Biennial Emergy Analysis
Conference, Center for Environmental Policy,
University of Florida, Gainesville.
Canaan Valley Institute (CVI) 2002. Mid-Atlantic
Highlands Action Plan, Transforming the Legacy,
Canaan Valley Institute, Thomas, WV.
Cohen, M.J., Sweeney, S. Brown, M.T. 2007.
Computing the Unit Emergy Value for Crustal
Elements, pp. 16.1-16.11. In Brown, M.T., Bardi, E.
Campbell, D.E., Comar, V., Huang, S.L. Rydberg, T.,
Tilley, D.R., Ulgiati, S. Emergy Synthesis 4, Theory
and Applications of the Emergy Methodology. ISBN:
978-0-9707325-8, Center for Environmental Policy,
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Essery, R., Pomerory, J., Parvianen, J., Storck, P. 2003.
Sublimation of snow from coniferous forests in a
climate model. Journal of Climate 16:1855-1864.
Felix, E. Tilley, D.R. 2008. Integrated energy,
environmental and financial analysis of ethanol
production from cellulosic switch grass. Energy
(submitted)
60
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Kibert, C.J., Sendzimir, J. Guy, G.B. (eds)
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Environmental Accounting Using Emergy: Minnesota
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Energy Systems Overview of the Amazon Basin.
Report to the Cousteau Society, Center for Wetlands,
CFW Publication #86-1, University of Florida,
Gainesville, FL. 190 p.
Odum, H.T., Odum, B.C., Blissett, M.: 1987, The Texas
System, Emergy Analysis and Public Policy. A Special
Project Report, L.B. Johnson School of Public Affairs.
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Natural Resources, Texas Department of Agriculture,
Austin.
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Arkansas. Center for Environmental Policy,
Environmental Engineering Sciences, University of
Florida, Gainesville, FL, 1998.
Odum, H.T., Odum, E.G., Brown, M.T. 1998b.
Environment and Society in Florida. St. Lucie Press,
Boca Raton, FL. 449 pp.
Odum, H.T., Brown, M.T., Brandt-Williams, S.L. 2000.
Handbook of Emergy Evaluation. Folio #1.
Introduction and Global Budget. Center for
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Lombardi, G., Coelho, O.F. 2003. Emergy comparison
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63
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Environmental Accounting Using Emergy: Minnesota
Section 6
Data Sources
1) USDA Nutrient Data Laboratory, Food Composition
and Nutrition, http://www.nal.usda.gov/fnic/cgi-
bin/nut_search.pl
2) U.S. Census, Commodity Flow Survey for 1997.
http://www.census.gov/econ/www/cdstate.html
3) Energy Information Administration:
http://www.eia.doe.gov
4) International Trade:
http://dataweb.usitc.gov/scripts/user_set.asp
5) Energy Information Administration (EIA) natural
gas:
http://www.eia.doe.gov/pub/oil_gas/natural_gas/data_pu
blications/natural_gas_annual/historical/1997/nga_l 997.
html
6) Energy Information Administration coal:
http://tonto.eia.doe.gov/FTPROOT/coal/058497.pdf
7)http://garnet.acns.fsu.edu/~tchapin/urp5261/topics/eco
nbase.htm
8)http: //www .nylovesbiz. com/ny sdc/Personalincome/stp
cpi9702.pdf
9) Minnesota Pollution Control Agency,
http://www.pca.state.mn.us/index.cfm
10) MN ethanol production,
http://blogs.citypages.com/blotter/2007/10/boom_boom
_bust.php, http://www.nass.usda.gov/mn/
11) http://www.deed.state.mn.us/facts/PDFs/food.pdf
12) http://www.allbusiness.com/government/3754093-
Lhtml,
http: //www .netstate. com/economy/mn_economy .htm
13) http://www.census .gov/statab/ranks/rank29 .html
14) http://www.eia.doe.gov/oss/forms.html#eia-7a
15) Snow:
http://www.windows.ucar.edu/tour/link=/earth/Water/w
ater_cycle_climate_change .html
16) Electricity from uranium,
http://www.ems.psu.edU/~elsworth/courses/cause2003/e
ngineofindustry/teamnuclear.ppt
17) Uranium Industry Annual report 2002, DOE/EIA-
0478(20020) http://www.eia.doe.gov/fuelnuclear.html
18) U.S. uranium mining
http://www.eia.doe.gov/cneaf/nuclear/uia/table03.html
19)http ://minerals .usgs .gov/minerals/pubs/commodity/ir
on_ore/stat/
20)http://wwwl.eere.energy.gov/industry/mining/pdfs/c
over.pdf
21)http://www.epa.gov/ttnecas l/regdata/IPs/Taconite_I
P.pdf
22)http ://minerals .usgs .gov/minerals/pubs/commodity/ir
on_ore/stat/
23) http://www.the-innovation-
group.com/ChemProfiles/Sulfur.htm
24)http://www.netstate.com/states/geography/mn_geogr
aphy.htm
25) http://www.dnr.state.mn.us/faq/mnfacts/water.html
26) NASA Surface Meteorology and Solar Energy
Website, http://eosweb.larc.nasa.gov/cgi-
bin/sse/register.cgi?task=login&next_url=/cgi-
bin/sse/ion-p&page=globe_main.ion&app=sse
27) National Renewable Energy Laboratory, Renewable
Resource Data Center.
http: //rredc .nrel .gov/wind/pubs/atlas/table s/1 -1 T.html
http://www.met.utah.edu/jhorel/html/wx/climate/windav
g.html
64
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Data Sources
28) Global Heat Flow Database of the International Heat
Flow Commission,
http: //www .heatflow .und. edu/index2 .html
29) Western Regional Climate Center, Average
precipitation (1900-2000)
http://www.wrcc.dri.edu/cgi-bin/divplotl_form.pl?2102
30) MN temperatures.
http: //www .dm. state .mn .us/faq/mnfacts/climate .html
31) Center for Natural Resources, UM- Duluth
http://www.cnr.umn.edu/FR/research/centcoop/mfric/tab
Ie3a.htm
32) Evapotranspiration Data,
http://walkerbranch.ornl.gov/ Estimated from graphs.
http://www.esd.ornl.gov/programs/WBW/NASA.htm
33) Net-State.com
http://www.netstate.com/states/tables/st_size.htm
3 4)http: //www .grow. arizona.edu/water/temperature/eva
poration.shtml
35) Precipitation
http://www.wcc.nrcs.usda.gov/climate/climate-map.html
36) MN County Areas
http://www.mnplan.state.mn.us/cgi-bin/datanetweb/
landuse?map=n&stats=y&topic=P&area=C
37) http://www.crh.noaa.gov/ncrfc/?n=2007outlook
38) Drainage Basin Information
http://www.pca.state.mn.us/water/basins/index.html
3 9) Runoff data
http://mn.water.usgs.gov/ann-repts/annrpt01/index.htm
40) Lake Superior Wave Statistics:
http://www.meds-sdmm.dfo-
o .gc .ca/alphapro/WAVE/TDCAtlas/TDCProducts .htm
41) Coastline
http://www.dnr.state.mn.us/waters/lakesuperior/feis/part
3.html
42) Flow of the St. Croix River
http://mn.water.usgs.gov/ann-
repts/annrptOO/05340500.2000.sw.pdf
43) Elevation at Danbury, WL,
http ://water.usgs .gov/pubs/wri/wri934076/stations/05 3 3
3500.html
44) Elevation at Reno, MN
http://download.geocomm.com/download.php
45) National Atmospheric Deposition Program/NTN
http://nadp.sws.uiuc.edu/
46) Ag Census 1997, Crop amounts. Table #1, #42.
http://www.nass.usda.gov/census/census97/volumel/ac9
7-mn.pdf
47) Ag Census 1997. Pounds/bushel for various crops.
Appendix F.
http://www.nass.usda.gov/census/census97/volumel/ac9
7-mn.pdf
48) Nutrient Data Laboratory
http ://www .nal .usda.gov/fnic/foodcomp/index.html
49) http://www.nass.usda.gov/census/indexl997.htm
50) http://www.unicamp .br/fea/ortega/creta/emergy .htm
51) Ag Census 2001 http://www.nass.usda.gov/mn/
52)http://jan.mannlib.cornell.edu/reports/nassr/livestock/
pls-bb/2000/lstk!200.pdf
53) Energy Information Administration, Total
Electricity Production (1997)
http: //www. eia. doe .gov/cneaf/electricity/epa/generation
_state.xls
54) http://www.engineeringtoolbox.com/wood-biomass-
combustion-heat-9_440 .html
http://mb-soft.eom/juca/print/311 .html
55) Forest growth
http://files.dnr.state.mn.us/forestry/um/2004mn_forest_r
esources.pdf
http://www.dnr.state.mn.us/forestry/um/index.html
56) U.S. Geological Survey, Ground Water Used (1995)
http ://water.usgs .gov/watuse/pdf 1995/pdf/summary .pdf
57)Water Quality http://mn.water.usgs.gov/ann-
repts/annrptOO/40000001.2000.wq.pdf
65
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Environmental Accounting Using Emergy: Minnesota
58) Municipal Solid Waste Generation and Disposal
http://www.pca.state.mn.us/programs/indicators/iom-
0201.html
59) EIA, Coal Consumption,
http://www.eia.doe.gov/cneaf/coal/cia/html/t67p01pl.ht
ml
72) 1997 Economic Census: Summary Statistics for
Minnesota,
http://www.census.gov/epcd/ec97/mn/MNOOO.HTM
73) U.S. Statistical Abstract 2002,
http: //www. census .gov/compendia/statab/past_years .ht
ml
60) EIA, Natural Gas,
http://www.eia.doe.gov/pub/oil_gas/natural_gas/data_pu
blications/natural^gas_annual/current/pdf/table_049.pdf
61) EIA, Petroleum
http://www.eia.doe.gov/emeu/states/sep_use/pet/use_pet
_mn.html
62) EIA, Electricity Production
http://www.eia.doe.gov/cneaf/electricity/epa/generation
_state.xls
63) EIA, Electricity Consumption.
http://www.eia.doe.gov/cneaf/electricity/st_profiles/sept
05mn.xls
64) http: //www. eia. doe .gov/cneaf/nuclear/
page/at_a_glance/state s/state smn .html
65) U.S.G.S. Mineral Yearbook
http://minerals.usgs.gov/minerals/pubs/state/mn.html
66) Wind Erosion,
http://www.nrcs.usda.gov/technical/NRI/1997/summary
_report/table 11 .html
67)Water Erosion,
http://www.nrcs.usda.gov/technical/NRI/1997/summary
_report/table 10 .html
68) Natural Resources Conservation Service,
http://www.mn.nrcs.usda.gov/technical/nri/tables/82-
971cu_basin.htm
69) http://server.admin.state.mn.us/mm/
indicator.html?Id=60&G=39&CI=60
70) Minnesota Department of Trade and Economic
Development, http://www.dted.state.mn.us/04xOOf.asp
71) Uranium price
http: //www .uranium .info/price s/longterm .html
74) IRS, http://www.irs.gov/pub/irs-soi/00db06co.xls,
http: //www. census .gov/population/censusdata/90den_stc
o.txt
75) 1997 Economic Census: Summary General Statistics
http://www.census.gov/epcd/ec97/wv/WVOOO.HTM
Summary Statistics for the U.S.,
http://www.census.gov/epcd/ec97/us/USOOO.HTM
By industry,
http://www.census.gov/epcd/ec97/industry/E3331 .HTM
Tables for Minnesota,
http://www.census.gov/govs/apes/96fedst.txt,
http://www.census.gov/govs/apes/97stlmn.txt
76) IRS, http://www.irs.gov/pub/irs-soi/00db06co.xls
77) Estimate from Minnesota DNR.
78) Water Quality for Minnesota's Water Basins,
http://www.pca.state.mn.us/water/groundwater/gwmap/
basins2.pdf
79) Lake Superior Volume/Shoreline,
http://www.glerl.noaa.gov/pr/ourlakes/lakes.html
80) Electrical Conductivity, Lake Superior,
http://wow.nrri.umn.edu/wow/under/parameters/conduct
ivity.html
81) Taconite Reserves,
http://www.taconite.org/pdfs/factsheet4.pdf
82) Twin cities Aggregate Resources
http://www.dnr.state.mn.us/lands_minerals/metroaggreg
ate .html
83) Aggregate maps
http: //www. dnr. state .mn .us/lands_minerals/aggregate_m
aps/index.html
84) Cu, NI, Pt, Assay
http://www.prnewswire.co.uk/cgi/news/release?id=9435
2
66
-------
Data Sources
85) Peat 87) Bureau of Economic Analysis, State GSP,
http://www.lmic.state.mn.us/chouse/metadata/peatmaps. http://www.bea.gov/bea/regional/gsp/
html
88) http://mup.asu.edu/research2006.pdf
86) U.S. Census Bureau, Population Statistics,
http://quickfacts.census.gov/qfd/states/27000.html 89) Propagation of error.
http://www.chem.usu.edu/~sbialkow/Classes/3600/Over
heads/Propagation/Prop .html
67
-------
Environmental Accounting Using Emergy: Minnesota
Section 7
Appendix A
Primary Symbols of the Energy Systems Language
68
-------
Appendix A
Energydrcut Apathv^whcseflowisprcpcdiaraltolhestoragea'saiBe
upstream
Source Afoxi^furdim(Talsidesajroe(i'aH^ddi\airgfcrces
accordingto aprogramoatrdled fixmcutside.
Tank AcarpartmentcrstatewiaHewitlinlhesystemsta^
as the balance cf inflows and outflows.
Heat sink Dispersion of potential energy into heat acooipanies all real
transfomatimprooessesardskrages. This energy is no longer usable by
the system
Interaction Meradiveinteraedimoftwopathv^yscxipledtoprodLioean
outflowmprcpatim to a function of both; a wok gate
Consumer An autocatalytic unit that transform energy, stores it and feeds
it backto improve inflow
Producer Hit that o3flelsandtiHrfanBlow<^tymergyundertheaxitrd
of high quality flows.
Box Msoeflaneou3synixitoiBefa'whate\eruata'funcdaiisneeded
SwitclvrgAfion AsymbolthatindcatescnecrmaBswitdm^adiaBcxrilrolled
by a logic program
Figure Al. Primary symbols of the Energy Systems Language.
69
-------
Environmental Accounting Using Emergy: Minnesota
Appendix B
Sources, Adjustment, and Calculation of Transformities
70
-------
Appendix B
Bl. Information Sources For The Emergy Per Unit Values Used In This Report.
The note number links the emergy per unit values listed in this table to the values used in Tables 4-8. The emergy
per unit values used in Table Bl.l are given to three significant figures and shown for the 9.26 and 15.83 E+24 sej/y
baselines. Values are transformities with units of sej/J except where other units are noted. For example where emergy
per unit mass is given a (g) for mass is noted next to the item and the units are sej/g. The emergy per unit of
education level is sej per individual and the emergy to dollar ratio (sej/$) is used for services. Table B3.1 gives the
factors used to convert one baseline to another. The 9.44 baseline was used by Odum (1996) and was revised to the
9.26 baseline by Campbell (2000a). The 9.44 values are not reported, because this baseline should no longer be used.
The 15.83 baseline values are reported because some emergy researchers have been using this baseline, which was
reported in Folio #2 (Odum 2000). All numbers given in the text of this report have been converted to the 9.26E+24
sej/y baseline by multiplying the number reported in the original source by the appropriate factor.
Table Bl.l The values and sources for transformities and specific emergies used in this report.
Note Item (per J unless noted)
Source of transformity or specific Emergy/unit Emergy/unit
emergy calculation 9.26 15.83
1 Incident solar radiation
2 Wind -
3 Earth Cycle
4 Rain, chemical potential
5 Evapotranspiration,
6 Rain, geo-potential, land
7 Snow, geo-potential, land
8 Rain, geo-potential runoff
9 Snow, geo-potential runoff
10 Rivers, chemical pot.
11 Rivers, geo-potential
12 Evapotranspiration
13 Ammonia fertilizer (g)
13 Ammonia, global (g)
13 NO,NO2,NO3 (g)
14 Sulfur, S (g)
15 Chlorine, Cl" (g)
16 Agricultural Products
A weighted average of:
17 Livestock
Beef cattle
18 Hydroelectricity
19 Net Timber Growth
20 Timber Harvest
21 Ground Water
22 Solid Waste (g)
23 Coal
24 Natural Gas
25 Crude Oil
26 Electricity
(by definition) 1
Odum (1996), p. 309 1470
Odum (1996), p. 309 33700
Odum (1996) Campbell (2003a) 18100
Odum (1996) Campbell (2003a) 28100
Odum (1996), p. 309 10300
This study 101000
Odum (1996) (errata) 27200
This study 101000
Odum (1996), Campbell (2003a) 50100
Odum (1996), p. 43 27200
Campbell (2003a) 28100
Odum (1996) 3.73E+09
Campbell (2003a) 1.39E+09
Campbell (2003b) 6.84E+09
This study 1.58E+11
This study 1.31E+10
Brandt-Williams (2002) variable
See B3 #7.
Odum et al. (1998) 3.36E+06
See B3 #7. 9.48E+05
Odum (1996), p. 186 120258
Tilley(1999),p.l50 20600
Tilley (1999) 68700
Odumetal. (1998a) 159000
Brown & Buranakarn (2000) 6.28E+09
Odum (1996), p. 310 39200
Bastianoni et al. (2005) 43500
Bastianoni et al. (2005) 54200
Odum (1996), p. 305& 311 170400
1
2.51E+03
5.76E+04
3.12E+04
4.80E+04
1.76E+04
1.73E+05
4.66E+04
1.73E+05
8.13E+04
4.66E+04
4.81E+04
6.37E+09
2.37E+9
1.17E+10
2.70E+11
2.24E+10
variable
2.06E+05
3.52E+04
1.17E+05
2.72E+05
1.07E+10
6.71E+04
7.44E+04
9.27E+04
2.91E+05
71
-------
Environmental Accounting Using Emergy: Minnesota
Note
27
28
32
33
33
34
34
35
37
37
38
39
40
49
53
NA
NA
Item (per J unless
Iron Ore
Sand and Gravel
Limestone
Dolomite
Dolomite
Peat
Peat
Erosion, topsoil
Nuclear Electricity
Uranium
Petroleum fuels
noted)
(g)
(g)
(g)
(g)
(g)
(g)
Aluminum ore, bauxite,
Steel
Forest Biomass
(g)
People (per individual)
Preschool
School
College Grad
Post-College
Elderly (65+)
Public Status
Legacy
Net Prod.
Aluminum
(md.)
(md.)
(md.)
(md.)
(md.)
(md.)
(md.)
(g)
Source of transformity or specific
emergy calculation
This study, 20% Fe
Campbell et al. (2005a)
Odum (1996)
This Study
This Study
Odum (1996) Tab. 5.4
Odum (1996) Tab. 5.4
Odum (1996)
This Study.
Cohen et al (2007)
Odum (1996)
Odum (1996)
This Study
Campbell et al. (2005a)
Odum (1988, 1996)
Campbell et al. (2005a)
Tilley(1999)p.l50
Brown & Buranakarn (2000)
Emergy/unit
9.26
3.51E+9
1.31E+09
9.81E+08
1.98E+07
1.08E+10
3.89E+08
1.86E+04
72600
4.81E+04
5.49E+11
64100
1.47E+07
1.47E+10
28200
3.E+16
9.E+16
3.E+17
l.E+18
1.69E+17
4.E+18
8.E+18
10800
1.23E+10
Emergy/unit
15.83
6.00E+09
2.24E+09
1.68E+09
3.38E+07
1.85E+10
6.65E+08
3.19E+04
1.24E+0
8.22E+4
9.39E+11
1.10E+05
2.52E+07
2.52E+10
4.82E+04
5.70E+16
1.58E+17
4.70E+17
2.20E+18
2.89E+17
6.59E+18
1.32E+19
1.84E+04
2.10E+10
B2. Estimation of Transformities for the SCTG Commodity Classes. Transformities and specific
emergies for each SCTG commodity classes were determined by averaging items within the class, for which
transformities were known. For classes where no transformities were available the transformity of the raw
materials was used as a first order estimate. Transformities for the SCTG commodity class codes are given
below as estimated from the transformities of the items listed. See Appendix D Table D1.1 for a definition of
the items represented by the SCTG Class Code numbers. Emergy per unit is relative to the 9.26 baseline.
Table B2.1 Transformities and Specific Emergies for the SCTG Commodity Classes.
Transformity Spec. Em.
Code Items in Class Average se/J sej/g
Avg. poultry and cattle, Odum et al (1987) Brandt-Williams (2001)
2 Avg. wheat, grain corn, rice, oats, sorghum, Odum et al. (1987) Brandt
Williams (2001)
3 Avg. soybeans, cotton, pecans, cabbages, oranges, etc. Odum et al. (1987)
Brandt-Williams (2001)
4 Forage Ulgiati et al (1994) Cornstalks & wool Odum (1996), eggs Brandt-
Williams (2001)
5 Meat ,veal, mutton, shrimp, Odum (1996).
439,300
181,800
233,400
1.22E6
3.27E6
72
-------
Code Items in Class Average
Transformity
sej/J
Appendix B
Spec. Em.
sej/g
6 use flour (wheat + energy to process) 18,1800
7 Sugar, palm oil and cacao from Odum et al. (1986b), milk Brandt-Williams
(2001). 1.12E6
8 Use ethanol and avg. 10% alcohol by volume for beer and wine,, Odum
(1996). 58,900
9 Use tobacco, Scatena et al (2002). 650,000
10 Use limestone Odum (1996). 9.81 E8
11 Use sand, this study. 1.31 E9
12 Use granite rocks Odum (1996). 4.91 E8
13 Use clay, Odum (1996). 1.96 E9
14 Use ore rocks, iron, alumina, copper, nickel, zinc Odum (1996). 2.71 E9
15 Use coal Odum (1996). 39,200
17 Use crude oil, petroleum fuels Odum (1996). 64,700
18 Use petroleum fuels Odum (1996). 64,700
19 Use fuel oil Odum (1996) 64,700
20 Use hydrated lime, caustic soda, diatomite, and sulfuric acid Odum et al. 2.75 E9
(2000b)
21 Pharmaceutical and biological products (use chemicals as feedstock) 2.75 E9
22 Fertilizer from Brandt-Williams (2001) and Odum (1996). 2.99 E9
23 Insecticide, paint and glue (Brown and Arding 1991cited in Buranakarn 9.90 E9
(1998).
24 (plastic, tires, etc.,) Odum et al. (1987) 2.71 E9
25 Use avg. Softwood and hardwood logs Odum (1996). 19,600
26 Use wood chips, lumber, particle board, plywood, Buranakarn (1998). 1.49 E 9
27 (Use avg. Wood pulp, paper, paper board), Tilley (1999) 139,800
28 Bags, packing, toilet paper, envelopes, wallpaper, Tilley (1999) 167,400
29 Paper from Tilley (1999) Ink assumed similar to other chemical preparations. 4.95 E9
30 Use avg. Of textiles and leather Odum et al. (1987) 7.18 E6
31 Use avg. Ceramics, glass flat and float, brick, concrete, Buranakarn (1998) 3.09 E9
32 Avg. Iron , steel, copper, aluminum Buranakarn (1998), Al 1/2 weight in avg. 5.91 E9
33 Assume articles of metal have similar transformities to the unformed metal. 5.91 E9
34 Machinery non electrical, Odum et. al. (1987), updated Cohen et al. (2007. 1.47E+10
35 Assume the transformity for machinery applies Odum et. al. (1987), updated 1.47E+10
Cohen et al. (2007).
36 Assume the transformity for machinery applies Odum et. al. (1987), updated 1.47E+10
Cohen et al. (2007).
37 Assume the transformity for machinery applies Odum et. al. (1987), updated 1.47E+10
Cohen et al. (2007).
38 Assume the transformity for machinery applies Odum et. al. (1987), updated 1.47E+10
Cohen et al. (2007).
39 Household furniture, lamps, mattresses use hardwood, Buranakarn (1998) 2.89 E9
40 Miscellaneous manufactured goods 1.61 E9
41 Tire waste, wood waste, slag. Buranakarn (1998) 2.16 E9
43 Corn and steel for groceries and hardware 6.32 E9
73
-------
Environmental Accounting Using Emergy: Minnesota
B3. Calculation of New or Revised Transformities. In all cases transformity is determined by dividing
the emergy (sej or sej/y) required for product or service by the energy (J or J/y) in the product or service.
Table. B3.1 Transformity of Snow
Average precipitation on land from 5 global water budgets in Campbell (2003a) was :
1 Oki(1999) 1.15E+14
2 Peixoto(1993) 9.90E+13
3 Baumgartner and Reichel ( 1975) 1.11E+14
4 L'vovich (1974) 1.10E+14
5 Odum 1996) 1.05E+14
Average precipitation on land from the 5 global water budgets 1 .08E+14
The transformity of snow was estimated from the mass fraction of total
precipitation assuming that all global precipitation is required for the ann
snowfall.
Average snow fall in a year 1 . 1 OE+ 1 3
Average residence time of snow (1 5) 120 days
Snow as a fraction of total precipitation (15) 1 .02E-0 1
Transformity of geopotential energy of precipitation on land is 10,300 sej/J
Transformity of geopotential energy delivered as snow 1.01E+05 sej/J
The dynamics of snow pack formation and its residence time could be used to make an alternate
determination of the transformitv of snow, but this was not done in this studv.
B3.2 Transformity of Dolomite
(l)Assume the production rate of dolomite is proportional to abundance.
(2) The production ratio of limestone to dolomite in the U.S. is 10/1, we assume this rate holds for the entire
world, and therefore, we can estimate the crustal abundance of dolomite. We also assumed that despite the
fact that dolomite production has not been observed, that it has been produced in the global sedimentary
cycle over the last cycle of mineral formation (Odum 1996).
Global Sedimentary Cycle Material Flux 9.36E+15 g/yr
The proportion of the continental area that is limestone is 18%, therefore, under the assumption statec
proportion of continental area of dolomite is 1.8%.
Limestone flux 1.68E+15 g/yr
Dolomite flux 1.68E+14 g/yr
Fraction mass flux 1.80E-02
Gibbs free energy of the weathered limestone (Odum 1996) 50 J/g
Calculation #1;
Solar transformity (sej/J)=(fraction*baseline)/(Gibbs free energy/g*flux in g/yr) Odum (1996) p. 46
Solar Transformity of Dolomite 1.98E+07 sej/J
74
-------
Appendix B
Calculation #2:
Specific emergy of dolomite =(0.981E9 sej/g) / (Gibbs Free 1.96E+07 sej/J
Energy) Odum (1996) p. 46
0.981E+9 sej/g is the emergy/mass of global sedimentary cycle on the 9.26 baseline
(Campbell 2000a)
Calculation #3:
sej/g based on limestone as 9.81E+08 sej/g
Mass ratio limestone/dolomite
Fraction total limestone dolomite 0.09090909
Specific emergy dolomite 1.08E+10 sej/g
B3.3 Updated Transformity for Electricity from Nuclear Power
Cohen et al. (2007) gives the specific emergy of uranium as 1.6E+1 Isej/g = 9.36E+10 sej/g
on the 9.26 baseline. Items in the table are from Lapp (1991) quoted in Odum (1996) on p.154.
Item sej/y
Emergy from the economy 9.128E+23
Emergy from the environment 4.90E+22
Emergy from uranium 6.37E+22
Total Emergy 1.03E+24
On 9.26 baseline 1.01E+24
Joules of electricity generated 2.09E+19
Transformity of nuclear electricity 4.81E+04 sej/J
Parameters
kWh per kg U fuel (16) 50000
kWh per year generated, Lapp (1991) 5.80E+12
tons U in fuel used (calculated) 1.16E+05
tons ore used (calculated) 7.63E+07
Specific Emergy U.S. Uranium* 5 492+1 \
* Specific Emergy from Cohen et al. (2007) is 1.6E+11 sej/g U adjusted to the 9.26 baseline is 9.36E+10 sej/g
U., adjusting for stoichiometry the average transformity of U3O8 is 7.94E+10 sej/g. Cohen's Ore Grade Cutoff
(OGC) is 0.026 % U and the percent U in U.S. mined ore is 0.152 giving an enrichment of 4.974.
Average uranium produced in the U.S. Mine n=10 Data Source (17)
Million Ibs U308 3.49
1000 MTU 1.35
75
-------
Environmental Accounting Using Emergy: Minnesota
Million Ibs U3O8
1000 MTU
Fraction U in U3O8 from data above
Stochiometry
Oxygen, MW 16
Uranium, MW 238
For $30 per pound U, all sources (mining + leaching)
Average ore grade percent U3O8
Concentrate n=10
4.26
1.64
0.850703226
0.847980998
128
714
0.17928
Data Source (1 7)
calculated
calculated
Data source (18)
B3.4 Transformity for Taconite
Energy use for Iron Extraction (20).
Year
Iron Ore Produced (1000 tons)
Energy Requirements for Extraction
Fuel Oil (1000 bbl.)
Natural Gas (billion cu. Ft.)
Gasoline (1000 bbl.)
Electricity Purchased (million kWh)
Total
Specific Emergy Added (sej/g)
Average Specific Emergy Added (sej4
1992
61288.5
669.6
29.7
26.2
7300
0
1997
69255.1
910.7
34.3
33.3
6200
1992
Joules
4.30E+15
3.27E+16
1.51E+11
2.63E+16
1997 Transformity 1992
Joules sej/J sej
5.85E+15
3.77E+16
5.03E+12
2.23E+16
64100
40000
64100
170400
2.76E+20
1.31E+21
9.67E+15
4.48E+21
6.06E+21
1.09E+08
1997
sej
.75E+20
.51E+21
.69E+21
.05E+07
76
-------
Appendix B
Production Costs 1997 (21)
Total $ Costs and Emergy of Service
Total Capital Expenditures
Buildings
Mineral Exploration
Mineral Land Rights
Total Labor
Payroll
Fringe
Total Cost of Supplies
Minerals and Machinery
Fuels
Electricity
Avg. service (sej /g)
1997 emergy/$ (sej/$)
$
1.68E+09
9.10E+07
8.14E+07
9.42E+06
1.06E+05
5.42E+08
3.94E+08
1.48E+08
1.04E+09
6.04E+08
1.17E+08
2.59E+08
6.56E+07
2.56E+12
sej/y
4.13E+21
2.08E+20
2.41E+19
2.71E+17
1.01E+21
3.78E+20
1.55E+21
3.00E+20
6.63E+20
Specific Emergy of Taconite Production
sej/g
Sedimentary Iron Ore (22) Cohen et al. (2007) (20% Fe) 3.51E+09
Emergy for Extraction and Processing 9.97E+07
Emergy in Services 6.56E+07
Emergy Per Gram of Taconite without Services 3.61E+09
Emergy per Gram Taconite with Services 3.68E+09
Emergy Magnification Factor For Extraction And Beneficiation 22.23
Emergy Magnification Factor Compared to 63% Fe Iron Ore 47.07
Specific Emergy of Taconite Production for Comparison
sej/g
Sedimentary Iron Ore Odum (1996) 9.81E+08
Emergy for Extraction and Processing 9.97E+07
Emergy in Services 6.56E+07
Emergy per Gram Taconite 1.15E+09
Emergy Magnification Factor For Extraction And Beneficiation 6.93
Emergy Magnification Factor Compared to 63% Fe Iron Ore 13.15
Nature's work in making ores with high iron concentration equivalent to that in taconite
pellets can be estimated as follows: The ratio of the fraction of iron in beneficiated pellets
to ore mined was 3.217 (0.6328/0.1967). Adjusting the specific emergy of iron (Cohen et
al. 2007) to an ore grade cut-off (OGC) of 63% iron gives a specific emergy of 1.13E+10
sej/g. The emergy magnification factors for the extraction and beneficiation technologies
using ore that is 20% iron are given above based on this number.
77
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Environmental Accounting Using Emergy: Minnesota
B3.5 Specific Emergy of Sulfur
Specific Emergy of Sulfur Estimated For Petroleum Refining (23)
Recovered Sulfur in the U.S. in 1999 (1000 Mt)
76% is from Petroleum Refining (1000 Mt)
Sulfur Recovered from Petroleum Refining (G) 6
Sulfur Production Capacity, U.S. Refineries 1999 (Long Tons)
Production Capacity (G)
Capacity Utilization
Emergy of Refining Average 1993-2004* (Sej/Y)
Specific Emergy of Recovered Sulfur (Sej/G)
Specific Emergy, if Process Was Run at Capacity (Sej/G)
Alternative Estimate for the Specific Emergy of Sulfur
8220
6247.2
.25E+12
12125
.23E+13
50.66%
.95E+24
.12E+11
.58E+11
* Bastianoni et al. manuscript, Campbell unpublished data
g/y
Sulfur Emissions, Volcanoes (Andreas & Kasgnoc 1998) 1.04E+13
Volcanic Extrusion at Surface (Odum 1996) 2.1 OE+15
Estimate of Sulfur Extruded 1.30E+12
Sulfur as a Fraction of Extruded Mass
Average Upper Crust Cone. S ppm (Rudnick & Gao
2003)
0.006
620
sej/g
Specific Emergy of Volcanic Extrusions (Odum 1996)
Specific Emergy Sulfur Based on Mass Concentration
4.41E+09
7.92E+11
78
-------
Appendix B
B3.6 Specific Emergy of the Chlorine Ion.
Adapted from the Calculation for Caustic Soda in Odum et al. (2000b) p. 263. All numbers converted to the
9.26 E+24 sej/y baseline
Solar Emergy Raw Units
Note
1
2
3
4
5
Notes:
1
Item
Salt (NaCl)
Water in Steam
Fuel
Capital and Labor
50% Caustic Soda
Salt. Amount necessa
(sej/g)
1.43E+09
7.91E+05
3.69E+09
5.39E+08
5.66E+09
,ry from stochiometric relation =
(J, g, $)
g
g
J
$
g
1.46g/gNaOH.
Emergy /Mass
(sej/g)
5.67E+09
Emergy/gram NaCl = 9.81 E8 sej/g (Odum 1996)
Emergy = (1.46 g/g NaOH)*(9.81 E8 sej/g) = 1.43 E9 sej/g NaOH
Water in steam. 8.85 g/g NaOH produced (Wehle, 1974, p. 197). Gibbs free
energy of water = 4.94 J/g. Transformity (rain) = 1.81 E4 sej/J (Odum 1996)
Emergy = (8.85 g)*(4.94 J/g)*(1.81 E4 sej/J) = 791313.9
Fuel for Electrolysis. 7.29 E7 BTU/ton NaOH (Wehle, 1974, p. 197)
Transformity of fuel (natural gas) = 43500 sej/J
Emergy = (7.29 E7 BTU/ton)*(l ton/9.07 E5 g)*(1054.8 J/BTU)*(43500 sej/J)
Labor & Service Purchased Goods. Price of Caustic Soda: $208/ton (4th quarter 2000)
Emergy to money ratio in 2000: 2.35E12 sej/$
Emergy = ($208/ton)*(l ton/9.07 E5 g)*(2.35 E12) = 5.39 E8
50% Caustic Soda. Sum of Inputs 1-4.
Molar Conversion from NaOH to Cl?:
Ig NaOH = 0.02439 mol
.02439 mol Cl —> 0.0122 mol C12 Specific emergy for C12:
.0122 mol C12 = 0.8662 g C12 6.55E+09 sej/g
Transformity for Cl : Use the reaction in water, assuming deposition is due to rain:
2H2O+C12 -> HC1O+H3O++ Cl"
0.0122 mol C12^ 0.0122 mol Cl"
0.0122 mol Cl" -> 0.4331 g Cl" Specific Emergy for Cl":
1.31E+10 sej/g
79
-------
Environmental Accounting Using Emergy: Minnesota
B3.7 Revised Transformities for Agricultural Products Including Some New Determinations for Minnesota.
Transformities for the agricultural products given in Brandt-Williams (2002) and Odum et al. (1998) were
recalculated with and without services using the 28100 sej/J as the transformity for evapotranspiration as in
Campbell et al. (2005) and using new values for the emergy to money ratio of the United States (Campbell and Lu
manuscript). The transformities without services included were used to determine the emergy of agricultural
commodity flows. All transformities are on the 9.26 E+24 sej/y planetary baseline. Table numbers and year of
study refer to Brandt-Williams (2001, revised 2002).
Key to Transformities Used
Item
Evapotranspiration
Topsoil loss
Fuel
Electricity
Potash
Lime
Phosphorus
Nitrogen
Pesticides
Labor
Services
Source
Campbell (2003a)
Odum 1996*0.981
Odum 1996*0.981
Odum 1996* 0.981
Odum 1996*0.981
Odum 1996*0.981
Brandt-Williams (2001 revised 2002)
*0.981
Brandt-Williams (2001 revised 2002)
*0.981
Brown and Arding (1991)
Unskilled, Odum 1996 * 0.981
Campbell and Lu (manuscript)
B3.7.1 Revised Transformities for Florida and Arkansas Crops and Livestock.
Modified from Brandt-Williams (2002)
Beef cattle (2 per ha)
Table 2
Item
Inputs
Units
Emergy per Unit
sej/(J, g, $)
1981 Evapotranspiration
Topsoil loss
Fuel
Potash
Lime
Phosphorus
Nitrogen
Pesticides
Labor
Services
Total w/o services
Total w services
Yield dry wt.
Yield energy
Specific emergy
Transformity w/o services
Transformity with services
1.15E+11
6.33E+07
1.20E+10
6.84E+04
5.52E+05
7.63E+03
3.09E+04
1.08E+04
8.40E+07
3.68E+02
5.72E+15
7.92E+15
1.84E+05
1.04E+10
3.11E+10
5.50E+05
7.62E+05
J
J
J
g
g
g
g
g
J
$
sej
sej
g
J
sej/g
sej/J
sej/J
28,100
72,398
64,746
1.707E+09
9.81E+08
2.158E+10
2.364E+10
1.452E+10
4.41E+06
4.97E+12
80
-------
Appendix B
Modified from Brandt-Williams (2002)
Eggs per 100 hens per year
Table 4
Modified from Brandt-Williams
Milk per cow per year
Table 16
Item
1988 Evapotranspiration
Topsoil loss
Fuel
Electricity
Potash
Lime
Phosphorus
Nitrogen
Pesticides
Labor
Services
Total w/o services
Total w services
Yield dry wt.
Yield energy
Specific emergy
Transformity w/o services
Transformity with services
(2002)
Item
1980 Evapotranspiration
Topsoil loss
Fuel
Electricity
Potash
Lime
Phosphorus
Nitrogen
Pesticides
Labor
Services
Total w/o services
Total w services
Yield dry wt.
Yield energy
Specific emergy
Transformity w/o services
Transformity with services
Inputs
ha1 y1
6.05E+10
4.25E+09
4.89E+10
3.06E+09
1.57E+05
5.25E+05
2.95E+04
7.99E+04
O.OOE+00
1.56E+10
1.21E+03
9.00E+15
8.17E+16
8.55E+05
2.08E+10
1.05E+10
4.33E+05
3.93E+06
Inputs
ha1 y1
1.51E+11
7.69E+09
1.75E+10
5.02E+09
1.49E+05
9.28E+05
3.35E+04
5.07E+04
2.33E+03
1.28E+08
2.19E+03
9.91E+15
2.26E+16
7.63E+05
1.98E+10
1.30E+10
5.01E+05
1.14E+06
Units
J
J
J
J
g
g
g
g
g
J
$
sej
sej
g
J
sej/g
sej/J
sej/J
Units
J
J
J
J
g
g
g
g
g
J
sej
sej
g
J
sej/g
sej/J
sej/J
Emergy per Unit
sej/(J, g, $)
28,100
72,398
64,746
170,694
1.71E+09
9.81E+08
2.16E+10
2.36E+10
1.45E+10
4.41E+06
3.17E+12
Emergy per Unit
sej/(J, g, $)
28,100
72,398
64,746
170,694
1.71E+09
9.81E+08
2.16E+10
2.36E+10
1.45E+10
4.41E+06
5.54E+12
81
-------
Environmental Accounting Using Emergy: Minnesota
Odum et al. (1998) Arkansas
Poultry (50,000 per ha, 3 months)
1977
Odum et al. (1998) Arkansas
Wheat
Item
Evapotranspiration
Topsoil loss
Fuel
Machinery (oil equivalent)
Ration corn
Ration soybeans
Electricity
Groundwater
Buildings (oil equivalent)
Services 1977$
Total w/o services
Total w services
Yield dry wt.
Yield energy
Specific emergy
Transformity w/o services
Transformity with services
Item
Evapotranspiration
topsoil loss
fuel
Machinery (oil equivalent)
Pesticide (oil equivalent)
Phosphate
Nitrogen
seed (oil equivalent)
electricity
groundwater
services 1977$
Total w/o services
Total w services
Yield dry wt.
Yield energy
Specific emergy
Transformity w/o services
Transformity with services
Inputs
ha1 y1
1.48E+10
9.95E+08
2.66E+11
1.64E+10
1.35E+12
5.82E+11
2.70E+10
1.79E+10
2.98E+11
8.02E+04
2.63E+17
8.63E+17
9.00E+07
8.02E+11
2.93E+09
3.28E+05
1.08E+06
Inputs
ha1 y1
1.48E+10
9.92E+08
4.98E+10
1.32E+09
1.79E+08
3.90E+05
1.95E+08
9.11E+08
1.79E+09
1.76E+10
2.60E+02
7.48E+15
9.36E+15
2.60E+06
3.81E+10
2.88E+09
1.96E+05
2.46E+05
Units
J
J
J
J
J
J
J
J
J
sej
sej
g
J
sej/g
sej/J
sej/J
Units
J
J
J
J
J
J
J
J
J
J
sej
sej
g
J
sej/g
sej/J
sej/J
Emergy per Unit
sej/(J, g, $)
28,100
72,398
64,746
64,746
66,123
2.54E+05
1.71E+05
1.67E+05
6.47E+04
7.23E+12
Emergy per Unit
se)/(J, g, $)
28,100
72,398
64,746
64,746
64,746
l.OOE+07
1.90E+06
6.47E+04
1.71E+05
1.67E+05
7.23E+12
82
-------
Appendix B
Odumetal. (1998)
Rice
Odumetal. (1998)
Corn
Item
Evapotranspiration
topsoil loss
fuel
Machinery (oil equivalent)
Pesticide (oil equivalent)
Nitrogen
Potassium
seed (oil equivalent)
electricity
groundwater
services 1977$
Total w/o services
Total w services
Yield dry wt.
Yield energy
Specific emergy
Transformity w/o services
Transformity with services
Item
Evapotranspiration
topsoil loss
fuel
Machinery (oil equivalent)
Pesticide (oil equivalent)
Nitrogen
Potassium
seed (oil equivalent)
electricity
Phosphate
services 1977$
Total w/o services
Total w services
Yield dry wt.
Yield energy
Specific emergy
Transformity w/o services
Transformity with services
Inputs
ha1 y1
1.48E+10
9.92E+08
1.35E+10
2.87E+08
3.97E+09
2.92E+08
2.36E+07
2.63E+09
3.78E+09
3.72E+10
7.30E+02
8.91E+15
1.42E+16
4.72E+06
6.95E+10
1.89E+09
1.28E+05
2.04E+05
Inputs
ha1 y1
1.48E+10
9.92E+08
6.82E+09
4.14E+09
9.28E+08
2.68E+08
4.00E+07
1.29E+09
6.85E+07
1.81E+07
3.53E+02
2.11E+15
4.66E+15
3.90E+06
6.95E+10
5.72E+10
3.03E+04
6.71E+04
Units
J
J
J
J
J
J
J
J
J
J
$
sej
sej
g
J
sej/g
sej/J
sej/J
Units
J
J
J
J
J
J
J
J
J
J
$
sej
sej
g
J
sej/g
sej/J
sej/J
Emergy per Unit
sej/(J, g, $)
28,100
72,398
64,746
64,746
64,746
1.86E+06
2.94E+06
6.47E+04
1.71E+05
1.57E+05
7.23E+12
Emergy per Unit
sej/(J, g, $)
28,100
72,398
64,746
64,746
64,746
1.86E+06
2.94E+06
6.47E+04
1.71E+05
7.70E+06
7.23E+12
83
-------
Environmental Accounting Using Emergy: Minnesota
Odumetal. (1998)
Sorghum
Item
Evapotranspiration
Topsoil loss
Fuel
Machinery (oil equivalent)
Pesticide (oil equivalent)
Phosphate
Nitrogen
Seed (oil equivalent)
Potassium
Ground-water
Services 1977$
Total w/o services
Total w services
Yield dry wt.
Yield energy
Specific emergy
Transformity w/o services
Transformity with services
Modified from Brandt-Williams (2002)
Corn (grain)
Table 15 Item
1987 Evapotranspiration
topsoil loss
fuel
electricity
potash
lime
phosphorus
nitrogen
pesticides
labor
services
Total w/o services
Total w services
Yield dry wt.
Yield energy
Specific emergy
Transformity w/o services
Transformity with services
Inputs
ha1 y1
1.48E+10
9.92E+08
2.99E+09
5.27E+08
5.78E+08
1.18E+06
8.20E+07
1.97E+08
6.31E+05
1.76E+10
1.47E+02
3.87E+15
4.93E+15
1.82E+06
3.87E+10
2.13E+09
l.OOE+05
1.27E+05
Inputs
ha1 y1
6.05E+10
4.25E+10
8.12E+09
7.85E+08
1.12E+05
3.73E+05
2.11E+04
5.71E+04
1.69E+03
1.32E+07
4.39E+02
7.82E+15
9.28E+15
9.17E+05
1.81E+10
8.53E+09
4.32E+05
5.12E+05
Units
J
J
J
J
J
J
J
J
J
J
$
sej
sej
g
J
sej/g
sej/J
sej/J
Units
J
J
J
J
g
g
g
g
g
J
$
sej
sej
g
J
sej/g
sej/J
sej/J
Emergy per Unit
sej/(J, g, $)
28,100
72,398
64,746
64,746
64,746
l.OOE+07
1.90E+06
6.47E+04
3.00E+06
1.67E+05
7.23E+12
Emergy per Unit
se)/(J, g, $)
28,100
72,398
64,746
170,694
1.71E+09
9.81E+08
2.16E+10
2.36E+10
1.45E+10
4.41E+06
3.17E+12
84
-------
Appendix B
Modified from Brandt-Williams (2002)
Corn (sweet)
Table 7
Modified from
Soybeans
Table 18
Item
1990 Evapotranspiration
topsoil loss
fuel
potash
lime
phosphorus
nitrogen
pesticides
labor
services
Total w/o services
Total w services
Yield dry wt.
Yield energy
Specific emergy
Transformity w/o services
Transformity with services
Brandt-Williams (2002)
Item
1989 Evapotranspiration
topsoil loss
fuel
electricity
potash
lime
phosphorus
nitrogen
pesticides
labor
services
Total w/o services
Total w services
Yield dry wt.
Yield energy
Specific emergy
Transformity w/o services
Transformity with services
Inputs
ha1 y1
6.05E+10
2.44E+10
1.25E+10
1.39E+05
O.OOE+00
3.95E+04
5.71E+04
1.11E+04
2.54E+08
7.76E+02
6.88E+15
1.02E+16
5.29E+06
1.04E+11
1.30E+09
6.61E+04
9.84E+04
Inputs
ha1 y1
6.15E+10
1.81E+07
7.01E+06
2.97E+08
3.73E+04
3.72E+05
1.05E+04
2.38E+03
7.07E+02
7.34E+06
1.48E+02
2.50E+15
2.98E+15
4.04E+05
9.86E+09
6.19E+09
2.54E+05
3.02E+05
Units
J
J
J
g
g
g
g
g
J
$
sej
sej
g
J
sej/g
sej/J
sej/J
Units
J
J
J
J
g
g
g
g
g
J
$
sej
sej
g
J
sej/g
sej/J
sej/J
Emergy per Unit
se)/(J, g, $)
28,100
72,398
64,746
1.71E+09
9.81E+08
2.16E+10
2.36E+10
1.45E+10
4.41E+06
2.88E+12
Emergy per Unit
se)/(J, g, $)
28,100
72,398
64,746
170,694
1.71E+09
9.81E+08
2.16E+10
2.36E+10
1.45E+10
4.41E+06
2.99E+12
85
-------
Environmental Accounting Using Emergy: Minnesota
Modified from Brandt-Williams (2002)
Oats
Table 17 Item
1985 Evapotranspiration
topsoil loss
fuel
electricity
potash
lime
phosphorus
nitrogen
pesticides
labor
services
Total w/o services
Total w services
Yield dry wt.
Yield energy
Specific emergy
Transformity w/o services
Transformity with services
Modified from Brandt-Williams (2002)
Peanuts
Table 11 Item
1987 Evapotranspiration
topsoil loss
fuel
electricity
potash
lime
phosphorus
nitrogen
pesticides
labor
services
Total w/o services
Total w services
Yield dry wt.
Yield energy
Specific emergy
Transformity w/o services
Transformity with services
Inputs
ha"1 y"1 Units
6.05E+10 J
7.69E+09 J
2.59E+09 J
O.OOE+00 J
9.29E+05 g
O.OOE+00 g
1.32E+04 g
5.11E+04 g
O.OOE+00 g
4.79E+06 J
1.30E+02 $
5.50E+15 sej
5.98E+15 sej
1.36E+06 g
2.72E+10 J
4.05E+09 sej/g
2.02E+05 sej/J
2.20E+05 sej/J
Inputs
ha1 y1
5.27E+10
7.69E+09
1.01E+10
2.05E+09
8.38E+04
9.04E+05
1.19E+04
3.56E+03
1.52E+03
3.00E+07
6.67E+02
4.43E+15
6.68E+15
2.95E+05
9.50E+09
1.50E+10
4.67E+05
7.04E+05
Emergy per Unit
1.
9.
Units
J
J
J
J
g
g
g
g
g
J
$
sej
sej
g
J
sej/g
sej/J
sej/J
sej/(J, g, $)
28,100
72,398
64,746
170,694
.71E+09
.81E+08
2.16E+10
2.36E+10
1.45E+10
4.41E+06
3.51E+12
Emergy per Unit
se)/(J, g, $)
28,100
72,398
64,746
170,694
1.71E+09
9.81E+08
2.16E+10
2.36E+10
1.45E+10
4.41E+06
3.17E+12
86
-------
Appendix B
Modified from Brandt-Williams (2002)
Cabbages
Table 6
Item
Inputs
ha1 y1
Units
Emergy per Unit
sej/(J, g, $)
1989 Evapotranspiration
topsoil loss
fuel
electricity
potash
lime
phosphorus
nitrogen
pesticides
labor
services
Total w/o services
Total w services
Yield dry wt.
Yield energy
Specific emergy
Transformity w/o services
Transformity with services
Modified from Brandt-Williams (2002)
Potatoes
Table 12 Item
1990 Evapotranspiration
topsoil loss
fuel
electricity
potash
lime
phosphorus
nitrogen
pesticides
labor
services
Total w/o services
Total w services
Yield dry wt.
Yield energy
Specific emergy
Transformity w/o services
Transformity with services
6.30E+10
7.69E+09
1.74E+10
1.36E+09
1.86E+05
5.65E+05
4.60E+04
4.75E+04
6.60E+03
2.05E+08
4.43E+02
6.77E+15
9.00E+15
2.31E+06
4.47E+10
2.93E+09
1.51E+05
2.01E+05
Inputs
ha1 y1
5.77E+10
7.69E+09
1.75E+10
1.36E+09
1.63E+05
5.65E+05
3.95E+04
4.75E+04
3.45E+04
1.37E+08
1.59E+03
6.85E+15
1.20E+16
5.43E+06
8.55E+10
1.26E+09
8.01E+04
1.41E+05
J
J
J
J
g
g
g
g
g
J
sej
sej
g
J
sej/g
sej/J
sej/J
Units
J
J
J
J
g
g
g
g
g
J
sej
sej
g
J
sej/g
sej/J
sej/J
28,100
72,398
64,746
170,694
1.71E+09
9.81E+08
2.16E+10
2.36E+10
1.45E+10
4.41E+06
2.99E+12
Emergy per Unit
se)/(J, g, $)
28,100
72,398
64,746
170,694
1.71E+09
9.81E+08
2.16E+10
2.36E+10
1.45E+10
4.41E+06
2.88E+12
2.22E+09
87
-------
Environmental Accounting Using Emergy: Minnesota
Modified from Brandt-Williams (2002)
Cucumbers
Table 8
Item
Inputs
Units
Emergy per Unit
sej/(J, g, $)
1990 Evapotranspiration
topsoil loss
fuel
electricity
potash
lime
phosphorus
nitrogen
pesticides
labor
services
Total w/o services
Total w services
Yield dry wt.
Yield energy
Specific emergy
Transformity w/o services
Transformity with services
Modified from Brandt-Williams (2002)
Green Beans
Table 9 Item
1990 Evapotranspiration
topsoil loss
fuel
electricity
potash
lime
phosphorus
nitrogen
pesticides
labor
services
Total w/o services
Total w services
Yield dry wt.
Yield energy
Specific emergy
Transformity w/o services
Transformity with services
6.02E+10
7.69E+09
2.19E+10
O.OOE+00
1.49E+05
5.65E+05
4.20E+04
4.75E+04
4.90E+04
6.41E+08
1.50E+03
7.22E+15
1.44E+16
1.33E+07
2.61E+11
5.43E+08
2.76E+04
5.50E+04
Inputs
ha1 y1
5.65E+10
7.69E+09
1.94E+10
1.65E+09
6.98E+04
5.65E+05
1.98E+04
2.38E+04
1.22E+04
6.23E+07
1.87E+03
5.52E+15
1.12E+16
5.55E+05
1.12E+10
9.95E+09
4.93E+05
9.98E+05
J
J
J
J
g
g
g
g
g
J
$
sej
sej
g
J
sej/g
sej/J
sej/J
Units
J
J
J
J
g
g
g
g
g
J
$
sej
sej
g
J
sej/g
sej/J
sej/J
28,100
72,398
64,746
170,694
1.71E+09
9.81E+08
2.16E+10
2.36E+10
1.45E+10
4.41E+06
2.88E+12
Emergy per Unit
se)/(J, g, $)
28,100
72,398
64,746
170,694
1.71E+09
9.81E+08
2.16E+10
2.36E+10
1.45E+10
4.41E+06
2.88E+12
-------
Appendix B
Modified from Brandt-Williams (2002)
Lettuce (Romaine)
Table 10 Item
1990 Evapotranspiration
topsoil loss
fuel
electricity
potash
lime
phosphorus
nitrogen
pesticides
labor
services
Total w/o services
Total w services
Yield dry wt.
Yield energy
Specific emergy
Transformity w/o services
Transformity with services
Modified from Brandt-Williams (2002)
Bell Peppers
Table 3 Item
1981 Evapotranspiration
topsoil loss
fuel
electricity
potash
lime
phosphorus
nitrogen
pesticides
labor
services
Total w/o services
Total w services
Yield dry wt.
Yield energy
Specific emergy
Transformity w/o services
Transformity with services
Inputs
ha1 y1
5.27E+10
7.69E+09
2.63E+10
O.OOE+00
1.86E+05
O.OOE+00
2.63E+04
4.75E+04
4.43E+04
3.87E+08
1.65E+03
6.39E+15
1.28E+16
8.08E+05
1.87E+10
7.91E+09
3.42E+05
6.87E+05
Inputs
ha1 y1
5.43E+10
7.69E+09
5.57E+10
7.49E+08
1.72E+05
O.OOE+00
5.27E+04
4.40E+04
1.31E+05
1.64E+09
2.11E+03
1.02E+16
2.79E+16
1.82E+06
3.87E+10
5.60E+09
2.63E+05
7.22E+05
Units
J
J
J
J
g
g
g
g
g
J
$
sej
sej
g
J
sej/g
sej/J
sej/J
Units
J
J
J
J
g
g
g
g
g
J
sej
sej
g
J
sej/g
sej/J
sej/J
Emergy per Unit
sej/(J, g, $)
28,100
72,398
64,746
170,694
1.71E+09
9.81E+08
2.16E+10
2.36E+10
1.45E+10
4.41E+06
2.88E+12
Emergy per Unit
se)/(J, g, $)
28,100
72,398
64,746
170,694
1.71E+09
9.81E+08
2.16E+10
2.36E+10
1.45E+10
4.41E+06
4.97E+12
89
-------
Environmental Accounting Using Emergy: Minnesota
Modified from Brandt-Williams (2002)
Tomatoes
Table 13
Modified from
Watermelons
Table 14
Item
1990 Evapotranspiration
topsoil loss
fuel
electricity
potash
lime
phosphorus
nitrogen
pesticides
labor
services
Total w/o services
Total w services
Yield dry wt.
Yield energy
Specific emergy
Transformity w/o services
Transformity with services
Brandt-Williams (2002)
Item
1981 Evapotranspiration
topsoil loss
fuel
electricity
potash
lime
phosphorus
nitrogen
pesticides
labor
services
Total w/o services
Total w services
Yield dry wt.
Yield energy
Specific emergy
Transformity w/o services
Transformity with services
Inputs
ha1 y1
6.02E+10
6.33E+07
7.37E+10
O.OOE+00
1.39E+05
3.29E+06
4.60E+04
4.75E+04
1.59E+05
8.56E+08
4.38E+03
1.44E+16
3.07E+16
2.43E+06
4.54E+10
5.91E+09
3.16E+05
6.77E+05
Inputs
ha1 y1
5.43E+10
7.69E+09
2.07E+10
O.OOE+00
7.44E+04
O.OOE+00
2.63E+04
2.86E+04
3.79E+04
4.00E+08
1.05E+03
5.34E+15
1.23E+16
1.88E+07
3.29E+11
2.84E+08
1.62E+04
3.75E+04
Units
J
J
J
J
g
g
g
g
g
J
$
sej
sej
g
J
sej/g
sej/J
sej/J
Units
J
J
J
J
g
g
g
g
g
J
$
sej
sej
g
J
sej/g
sej/J
sej/J
Emergy per Unit
sej/(J, g, $)
28,100
72,398
64,746
170,694
1.71E+09
9.81E+08
2.16E+10
2.36E+10
1.45E+10
4.41E+06
2.88E+12
Emergy per Unit
se)/(J, g, $)
28,100
72,398
64,746
170,694
1.71E+09
9.81E+08
2.16E+10
2.36E+10
1.45E+10
4.41E+06
4.97E+12
90
-------
Appendix B
Modified from Brandt-Williams (2002)
Oranges
Table 5
Modified from
Pecans
Table 22
Item
1983 Evapotranspiration
topsoil loss
fuel
electricity
potash
lime
phosphorus
nitrogen
pesticides
labor
services
Total w/o services
Total w services
Yield dry wt.
Yield energy
Specific emergy
Transformity w/o services
Transformity with services
Brandt-Williams (2002)
Item
1989 Evapotranspiration
topsoil loss
fuel
electricity
potash
lime
phosphorus
nitrogen
pesticides
labor
services
Total w/o services
Total w services
Yield dry wt.
Yield energy
Specific emergy
Transformity w/o services
Transformity with services
Inputs
ha1 y1
6.51E+10
6.33E+08
1.99E+10
4.68E+08
2.36E+05
2.40E+05
1.12E+04
3.01E+04
1.79E+04
2.71E+08
3.01E+02
5.09E+15
7.43E+15
4.91E+06
8.65E+10
1.04E+09
5.89E+04
8.59E+04
Inputs
ha1 y1
6.50E+10
6.33E+08
1.32E+10
2.96E+08
7.54E+04
3.73E+05
2.11E+04
4.88E+04
7.20E+03
4.53E+07
2.11E+03
4.99E+15
1.15E+16
8.00E+05
2.30E+10
6.23E+09
2.17E+05
5.00E+05
Units
J
J
J
J
gK
g
g P
gN
g
J
$
sej
sej
g
J
sej/g
sej/J
sej/J
Units
J
J
J
J
g
g
g
g
g
J
$
sej
sej
g
J
sej/g
sej/J
sej/J
Emergy per Unit
sej/(J, g, $)
28,100
72,398
64,746
170,694
1.71E+09
9.81E+08
2.16E+10
2.36E+10
1.45E+10
4.41E+06
3.79E+12
Emergy per Unit
se)/(J, g, $)
28,100
72,398
64,746
170,694
1.71E+09
9.81E+08
2.16E+10
2.36E+10
1.45E+10
4.41E+06
2.99E+12
91
-------
Environmental Accounting Using Emergy: Minnesota
Modified from Brandt-Williams (2002)
Sugarcane
Table 19
Modified from
Cotton
Table 20
Item
1985 Evapotranspiration
topsoil loss
fuel
electricity
potash
lime
phosphorus
nitrogen
pesticides
labor
services
Total w/o services
Total w services
Yield dry wt.
Yield energy
Specific emergy
Transformity w/o services
Transformity with services
Brandt-Williams (2002)
Item
1987 Evapotranspiration
topsoil loss
fuel
electricity
potash
lime
phosphorus
nitrogen
pesticides
labor
services
Total w/o services
Total w services
Yield dry wt.
Yield energy
Specific emergy
Transformity w/o services
Transformity with services
Inputs
ha1 y1
6.83E+10
7.69E+09
5.46E+09
O.OOE+00
1.49E+05
O.OOE+00
1.05E+04
O.OOE+00
1.96E+03
1.37E+07
1.35E+03
3.34E+15
3.40E+15
2.27E+07
4.12E+11
1.47E+08
8.10E+03
8.25E+03
Inputs
ha1 y1
5.80E+10
8.23E+10
9.70E+09
3.15E+08
7.44E+04
5.65E+05
1.58E+04
1.90E+04
4.97E+03
8.90E+07
4.07E+02
9.81E+15
1.15E+16
7.38E+05
1.25E+10
1.33E+10
7.85E+05
9.20E+05
Units
J
J
J
J
g
g
g
g
g
J
$
sej
sej
g
J
sej/g
sej/J
sej/J
Units
J
J
J
J
g
g
g
g
g
J
$
sej
sej
g
J
sej/g
sej/J
sej/J
Emergy per Unit
sej/(J, g, $)
28,100
72,398
64,746
170,694
1.71E+09
9.81E+08
2.16E+10
2.36E+10
1.45E+10
4.41E+06
1.99E+03
Emergy per Unit
sej/(J5 g, $)
28,100
72,398
64,746
170,694
1.71E+09
9.81E+08
2.16E+10
2.36E+10
1.45E+10
4.41E+06
3.17E+12
92
-------
Appendix B
Modified from Brandt-Williams (2002)
Pasture (Bahia Grass)
Table 21
Item
Inputs Emergy per Unit
ha"1 y"1 Units sej/(J, g, $)
1985 Evapotranspiration
topsoil loss
fuel
electricity
potash
lime
phosphorus
nitrogen
pesticides
labor
services
Total w/o services
Total w services
Yield dry wt.
Yield energy
Specific emergy
Transformity w/o services
Transformity with services
5.43E+10
6.33E+07
2.46E+09
2.22E+08
3.63E+04
3.73E+05
7.38E+03
1.55E+04
O.OOE+00
4.85E+06
2.24E+01
2.68E+15
2.78E+15
3.63E+06
6.88E+10
7.39E+08
3.90E+04
4.04E+04
J
J
J
J
g
g
g
g
g
J
$
sej
sej
g
J
sej/g
sej/J
sej/J
28,100
72,398
64,746
170,694
1.71E+09
9.81E+08
2.16E+10
2.36E+10
1.45E+10
4.41E+06
3.51E+12
B3.7.2. Minnesota Agriculture
New transformities calculated for a study to determine the empower density of Minnesota agriculture.
Dairy (Minnesota)
Milk per cow per year
Item
Inputs Emergy per Unit
ha"1 y"1 Units sej/(J, g, $)
1980
Evapotranspiration
Topsoil loss
Fuel
Electricity
Potash
Lime
Phosphorus
Nitrogen
Pesticides
Labor
Services
Total w services
Total w/o services
Yield dry wt.
Yield energy
Specific emergy
Transformity w/o services
Transformity with services
1.51E+11
7.69E+09
2.26E+09
l.OOE+09
1.49E+05
9.28E+05
3.35E+04
5.07E+04
2.33E+03
1.28E+08
2.19E+03
8.24E+15
2.09E+16
7.63E+05
1.98E+10
1.08E+10
4.16E+05
1.06E+06
J
J
J
g
g
g
g
g
J
$
sej
sej
g
J
sej/g
sej/J
sej/J
28,100
72,398
64,746
170,694
1.71E+09
9.81E+08
2.16E+10
2.36E+10
1.45E+10
4414500
5.54E+12
93
-------
Environmental Accounting Using Emergy: Minnesota
Spring Wheat (Minnesota)
Grain Corn (Minnesota)
1987
Item
Evapotranspiration
Topsoil loss
Fuel
Potash
Pesticide and herbicide
Phosphate
Nitrogen
Labor
Electricity
Groundwater
Services 2003$
Total w services
Total w/o services
Yield dry wt.
Yield energy
Specific emergy
Transformity w/o services
Transformity with services
Item
Evapotranspiration
Topsoil loss
Fuel
Electricity
Potash
Herbicide
Phosphorus
Nitrogen
Pesticides
Labor
Operator
Services
Total w/o services
Total w services
Yield dry wt.
Yield energy
Specific emergy
Transformity w/o services
Transformity with services
Inputs
ha1 y1
1.29E+10
1.91E+10
5.06E+08
4.00E+03
5.66E+02
5.95E+03
1.37E+04
3.88E+06
4.35E+07
O.OOE+00
4.09E+02
2.27E+15
3.09E+15
2.14E+06
3.04E+10
1.06E+09
7.48E+04
1.02E+05
Inputs
ha1 y1
2.55E+10
1.11E+10
9.96E+08
5.19E+07
9.98E+03
2.84E+03
7.83E+03
2.49E+04
6.16E+02
3.88E+06
7.75E+06
6.27E+02
2.42E+15
4.43E+15
3.46E+06
6.81E+10
7.00E+08
3.55E+04
6.50E+04
Units
J
J
J
g
g
g
g
J
J
J
$
sej
sej
g
J
sej/g
sej/J
sej/J
Units
J
J
J
J
g
g
g
g
g
J
J
$
sej
sej
g
J
sej/g
sej/J
sej/J
Emergy per Unit
sej/(J, g, $)
28,100
72,398
64,746
1.71E+09
1.45E+10
2.16E+10
2.36E+10
4.41E+06
1.71E+05
1.67E+05
2.00E+12
Emergy per Unit
se)/(J, g, $)
28,100
72,398
64,746
170,694
1.71E+09
1.4519E+10
2.1582E+10
2.3642E+10
1.4519E+10
4.41E+06
7.19E+07
3.17E+12
94
-------
Appendix B
Soybeans (Minnesota)
1989
Item
Evapotranspiration
Topsoil loss
Fuel
Electricity
Potash
Herbicide
Phosphorus
Nitrogen
Pesticides
Labor
Operator
Services
Total w/o services
Total w services
Yield dry wt.
Yield energy
Specific emergy
Transformity w/o services
transfbrmity with services
Inputs
ha1 y1
2.55E+10
1.11E+10
5.15E+08
4.95E+05
1.63E+03
1.61E+03
1.27E+03
1.01E+03
8.63E+02
3.88E+06
7.75E+06
4.20E+02
1.64E+15
2.92E+15
9.41E+05
2.30E+10
1.75E+09
7.16E+04
1.27E+05
Units
J
J
J
J
g
g
g
g
g
J
J
$
sej
sej
g
J
sej/g
sej/J
sej/J
Emergy per Unit
sej/(J, g, $)
28,100
72,398
64,746
170,694
1706940000
1.4519E+10
2.1582E+10
2.3642E+10
1.4519E+10
4.41E+06
7.19E+07
2.99E+12
B3.7.2.1 Inputs for Minnesota Dairy per cwt Milk and assuming 172 cwt/cow
Prices 1995
Diesel
Gasoline
LPG
Electricity
$/gal, cents/kWh
0.77
1.11
0.73
0.05
Note: 1995 Prices are used to estimate fuel and electricity inputs to all Minnesota crops.
Milk Production
$ Cost/acre
Nitrogen
Phosphorus
Potash
Fuel type
gal, per acre kWh/ ac. J/m2/cwt/y
Fertilizer (Ibs per treatment * # treatments *%treated)
Ibs/acre/y g/ha/y
75
32
22
13,714
5,947
3,996
J/cow/y
0.10
0.02
0.08
0.20
0.40
Diesel
Gasoline
LPG
Total Fuels
Electricity
Total Cost
0.13
0.02
0.11
7.60E+06
1.11E+06
4.41E+06
1.31E+07
4 5.83E+06
1.31E+09
1.91E+08
7.59E+08
2.26E+09
l.OOE+09
95
-------
Environmental Accounting Using Emergy: Minnesota
Pesticide
(Ibs per treatment * # treatments *%treated)
Chlorpyrifos
Permethrin
Phorate
Terbufos
Total
Ibs/acre/y
0.94
0.11
1.11
1.19
g/ha/y
172.71
20.21
203.94
218.64
615.51
Herbicides: 2,4D, Bromoxynil, Dicamba, Diclofop-methyl, Fenoxaprop-ethyl,
Imazamethabenz-methy, MCPAC, Thifensulfron, Triallate, Tribenuron-methyl
Total
Ibs/acre/y
3.08
g/ha/y
565.53
Services 2003
$/acre
165.75
Labor
$/ha
409.40
hours/acre
hours/ha
J/ha/y Labor expense,
Operator
Unskilled
Avg. Yield
1995-2001
0.00
1.00
bu/acre
136
0.00
2.47
g/acre
3,457,664
0.00
3.88E+06
7.01
B3.7.2.2 Inputs for Minnesota Corn
Use 1995 prices for fuels.
Corn Production
$ cost/acre
Fertilizer
Pesticide
Fuel type
gal, per acre
kWh/ acre
J/ha/y
7.21
1.28
6.99
1.78
17.27
Diesel
Gasoline
LPG
Total Fuels
Electricity
Total
9.37
1.15
9.58
5.48E+08
6.38E+07
3.84E+08
9.96E+08
35.63 5.19E+07
(Ibs per treatment * # treatments *%treated)
Ibs/acre/y g/ha/y
Nitrogen
Phosphorus
Potash
105
43
54
19,263
7,826
9,983
(Ibs per treatment * # treatments *%treated)
Ibs/acre/y
g/ha/y
Ibs/acre/y
g/ha/y
Chlorpyrifos
Permethrin
Phorate
Terbufos
0.94
0.11
1.11
1.19
172.71
20.21
203.94
218.64
615.51
135.36 24870
96
-------
Appendix B
Herbicide: 2,4D, Alachlor, Atrazinw, Bromoxynil, Cyanazine, Dicamba, ETC, Metolachlor,
Nicosulfuron, Pendimethakin, Propaclor
Ibs/acre/y g/ha/y
All in order
Services 2002
15.47
$/acre
2,842.36
$/ha
Labor
Operator
Unskilled
Yield
B3.7.2.3 Inputs for
Transpiration rate
Growing season
Transpiration
Energy Wheat
trans.
Erosion Rate
Erosion Rate
Energy of Erosion
Use 1995 Prices
254
hours/acre
2
1
bu/acre
136
Minnesota Wheat
3
90
0.27
1.29E+10
12.6
28.2338784
1.91E+10
627.38
hours/ha
4.94
2.47
R
3,457,664
mm/d
day
m
J/y
short tons/acre/y
MT/ha
J/y
J/ha/y
7.75E+06
3.88E+06
J/R
19,690
Wheat Production
$ cost/acre
Fuel type
gal./ acre kWh/ acre J/ha/y
5.57
0.99
0.60
1.49
8.66
Diesel
Gasoline
LPG
Total Fuels
Electricity
Total Cost
7.24
0.89
0.82
4.23E+08
4.94E+07
3.29E+07
5.06E+08
29.88 4.35E+07
Fertilizer, herbicide and service inputs are assumed similar to dairy above.
Wheat Yield bu/acre Ibs dry wt./bu J/g
34
B3.7.2.4 Inputs for Minnesota Soybeans
Use 1995 Prices given above.
56
14,230
Soybean Production
$ cost/acre Fuel type
gal ./acre kWh/ acre
J/ha/y
5.72
1.01
0.55
0.02
7.30
Diesel
Gasoline
LPG
Total Fuels
Electricity
Total Cost
7.43
0.91
0.75
4.35E+08
5.05E+07
3.01E+07
5.15E+08
0.34 4.95E+05
97
-------
Environmental Accounting Using Emergy: Minnesota
Fertilizer (Ibs per treatment * # treatments *%treated)
Ibs/acre/y g/ha/y
Nitrogen
Phosphorus
Potash
6
7
9
1,011
1,269
1,627
Pesticide (Ibs per treatment * # treatments *%treated)
Ibs/acre/y g/ha/y
Chlorpyrifos
Permethrin
Phorate
Terbufos
Total
No data
No data
No data
No data
No data
No data
No data
No data
863.46
Herbicides used: 2,4-D, Aciflourfen, Alachlor, Bentazon, Ethalfluralin, Fluazifop-p
butyl, Glphosate, Imazethapyr, Metolachlor, Metribuzin, Pendimethalin,
Quizalofop ethyl, Sethoxydim, Thifensulfuron, Trifluralin, Propachlor
Ibs/acre/y g/ha/y
All herbicides 8.76 1,610
Services 2002
Labor
Operator
Unskilled
Yield
$/acre
170
hours/acre
2
1
bu/acre
37
$/ha
419.9
hours/ha
4.94
2.47
g/ha
940,688
J/ha/y
7.75E+06
3.88E+06
J/g
24,420
B3.8 Revised Transformities for Fossil Fuels
There are two major ways to determine the transformities of fossil fuels. The first
method is based on back calculation from solar based electricity using relative quality
factors. This was the original way that the fossil fuel transformities were determined
by Odum (1996), The second method is to calculate the transformity based on the
geological process of formation of the mineral. Odum used both the first and second
methods for coal in Odum (1996). The transformities for oil and natural gas were
determined by the first method only in 1996, but coal was determined using both
methods. Bastianoni et al. (2005) calculated the transformity for oil and petroleum
natural gas by the second method. Their results closely conformed to Odum's original
numbers determined by the first method. The transformity of oil being slightly and
higher and the transformity of natural gas slightly lower than the original numbers.
Odum (1996) used an average of the two methods to determine a transformity for coal.
If a similar average is used for oil and natural gas we obtain the following numbers.
All numbers are expressed relative to the 9.26E+24 sej/y planetary baseline, which is
the corrected version of Odum's 9.44 line used in Odum (1996).
98
-------
Appendix B
Fossil Fuel Transformities sej J"1
Relative Efficiency Geologic Processes Average 3 sig. figs.
Coal
Natural gas
Oil
42,180
47,080
52,640
33,350
40,000
55,400
37,770
43,540
54,020
37,800
43,500
54,000
Table B4.1 The factors needed to convert one planetary baseline to another.
To convert,
Multiply
Baseline X
9.44
9.44
9.26
9.26
15.83
15.83
To baseline, Y
9.26
15.83
9.44
15.83
9.26
9.44
by
0.981
1.677
1.019
1.710
0.585
0.596
Table B4.2 Emergy to Money Ratio of the United States for 1997 and 2000
These numbers are different from those used in the West Virginia Report (Campbell et al.
2005a). These preliminary values are taken from a new study of the Emergy to Money
Ratio for the United States from 1900 to 2004, which is a manuscript by Campbell and Lu
to be published later this year.
Year sei/$
1997 2.56E+12
2000 2.35E+12
99
-------
Environmental Accounting Using Emergy: Minnesota
Appendix C
Calculation of Energy and Economic Values
Used to Determine the 1997 Energy
and Emergy Accounts for Minnesota
100
-------
Appendix C
Cl Notes for Table 4 - Annual Renewable Resources and Production in 1997.
The numbers in parentheses and italics refer to data sources given above. The notation E+3 = 103.
Note
Total Area (24) 2.25E+11 m2
Land area 1.72E+11 m2
Water Area (25) 1.55E+10 m2
Area of inland water and wetlands 5.32E+10 m2
Wetlands 2003 3.76E+10 m2
Wetlands 1850 7.53E+10 m2
Surface Waters 1.55E+10 m2
1 Solar Energy Received 1.074E+21JV1
Absorbed 8.841E+20 J y'1
Solar energy received (J) = (avg. insolation)(area)(365 day/y)(4186 J/kcal)
Solar energy absorbed = (received) (1-albedo)
The average insolation and albedo were obtained from the NASA website (26) referenced in sources. Twenty-
six, one-degree latitude by one-degree longitude, sectors covering the state were averaged.
kWh/m2/y J/m2/y
Solar energy received over the state 1324 4.77E+09
Solar energy absorbed by the state 1091 3.93E+09
2 Kinetic Energy of Wind Used at the Surface 1.2639+19 J y"1
Wind energy = (density)(drag coefficient)(geostrophic wind velocity)3(area)(sec/year)
This formula is given in a manuscript by Odum (1999) titled "Evaluating Landscape Use of
Wind Kinetic Energy".
The wind velocity used was taken from the National Renewable Energy Laboratory (NREL)
web site (59). The common drag coefficient over water is about 1 .OE-3 for ordinary winds
of 10 m/s or less (Miller 1964) 2.OE-3 over land and 3.OE-3 over low mountains Garratt (1977).
Winds over land are about 0.6 of the wind velocity that the pressure system would generate in
the absence of friction (Reiter 1969).
Area NREL Class #2 (27)
Air Density 1.3 kg m"3
Geostrophic Wind 7.92 m/s
Drag Coefficient 2.00E-03 dimensionless
Area of Class 9.5490 E+10 m2
Sec/Year 3.16E+07
Energy 3.89E+18 J/yr
Area NREL Class #3 (27)
Air Density 1.3 kg m"3
Geostrophic Wind 8.92 m/s
Drag Coefficient 2.00E-03 dimensionless
101
-------
-1
Environmental Accounting Using Emergy: Minnesota
Area 5.3927E+10m2
Sec/Year 3.16E+07
Energy 3.14E+18J/yr
Area NREL Class #4 (27)
Air Density 1.3 kg m"3
Geostrophic Wind 9.67 m/s
Drag Coefficient 2.00E-03 dimensionless
Area 7.5762E+10 m2
Sec/Year 3.16E+07
Energy 5.61E+18 J/yr
3 Earth Cycle Energy 2.80E+17 J y
Earth cycle energy (steady-state uplift balanced by erosion) =
(land area) (heat flow/area)
The heat flow per area is an average of nine wells throughout the state (28).
Area 2.252E+llm2
Heat flow/area 39.40 mW m'2
1.24E+06 Jm2yr1
4 Rain Chemical Potential 7.07E+17 J y'1
Chemical potential energy in rain =
(area)(rainfall)(density water)(Gibbs Free Energy water relative to seawater)
Average annual rainfall based on a one hundred year average from the
Western Regional Climate Center (29) and temperature of the growing season (30).
Area 2.2518 E+llm2
Rainfall 0.658 m/y
Gibbs Free Energy (Odum 1996) 4.77 J/g
Density 1.00E+06g/m3
5 Chemical Potential Energy of Evapotranspiration 3.14E+17 J y"1
Chemical potential energy in evapotranspiration =
(Area in land use)(Evapotranspiration for that use)(Density)(Gibbs Free Energy per gram)
In general, forest evapotranspiration can be estimated as 0.85 times pan evaporation
(Odum et al. (1998). Forest area data is from UM-Duluth (31) and forest evapotranspiration
was estimated using Oak Ridge National Laboratory data from Walker Branch, TN (32). Evapotranspiration
rates for crops and pasture from Arnold and Williams (1985) and
Ritter et al. (1985). The area of wetlands is from Net-State data (33) and wetland
evapotranspiration was estimated using Hussey and Odum (1992) by using the average
of peak beginning and end from their data, along with Water Resources data from the
University of Arizona (34).
Deciduous Forest Area 4.80E+10 m2
Evapotranspiration l.SSE-Olmy"1
1.00E+06gm-3
4.771^
102
-------
Appendix C
Energy
Coniferous Forest Area
Evapotranspiration
Energy
Crop Area
Evapotranspiration
Energy
Wetlands Area
Evapotranspiration
Energy
Total Area
Urban & Barren Area
(by difference)
4.19E+16 J/y
1.82E+10m2
1.83E-01my-
1.59E+16 Jy"1
8.70E+10 m2
4.50E-01 my"
1.87E+17 Jy"1
3.76E+10m2
3.88E-01my"
6.97E+16 Jy1
1.91E+llm2
3.43E+10m2
Geopotential Energy of Rain and Snow on Land
Rain
Snow
4.58E+17JV1
7.22E+16 J y'1
Geo-potential energy = (area)(mean elevation)(rainfall)(density)(gravity)
An area weighted average of rainfall (35) and elevation by county (36) was used
to determine the geopotential energy of rain and snow on land. We assumed that
on average snow is 7.5% water (37). In the Table below the superscripts have the following meaning
*: Estimated Elev.
T: Estimated Precipitation and Snow. Averaged from the given values of the bordering
counties.
103
-------
Environmental Accounting Using Emergy: Minnesota
Table Cl.l. Data used to determine the geopotential energy of rainfall.
County
Aitkin
Anoka
Becker
Beltrami
Benton *T
Big Stone
Blue Earth *T
Brown
Carlton
Carver
Cass
Chippewa
Chisago
Clay
Clearwater
Cook
Cottonwood
Crow Wing
Dakota
Dodge*1
Douglas*1
Faribault
Fillmore
Freeborn
Goodhue
Grant*
Hennepin
Houston
Hubbard
Isanti
Itasca
Jackson
Kanabec
Kandiyohi
Kittson
Koochiching
Lac Qui Parle
Lake
Lake of the Woods
Le Seuer*
Lincoln
Lyon
McLeod
Area m2
5163064408
1153730438
3743560721
7911341260
1968803109
1368974637
1981729403
1600944494
2265235967
972997830
6248852173
1523188195
1145151102
2728649599
2666918850
4158606316
1679591102
2993787491
1517453800
1137712980
1865204219
1868101768
2231752286
1869481746
2018053986
1491505356
1570580930
1472687474
2587993010
1167821592
7577079013
1862581856
1380767177
2233225342
2860888726
8162614622
2016645680
5922744342
4609203544
1226270339
1421612099
1869975463
1308542930
Elev. (m)
384.048
277.368
451.104
387.096
347.472
329.184
231.648
294.132
362.712
219.456
408.432
310.896
277.368
271.272
454.152
185.928
420.624
371.856
295.656
335.28
362.712
335.28
329.184
374.904
256.032
298.704
274.32
381
438.912
304.8
396.24
198.12
301.752
362.712
356.616
371.856
316.992
402.336
329.184
237.744
533.4
377.952
326.136
Precip. (m)
0.721360
0.796290
0.616204
0.735076
0.721868
0.612902
0.769366
0.715772
0.779018
0.769874
0.663448
0.628396
0.802132
0.564642
0.6858
0.626618
0.733552
0.71374
0.837438
0.81407
0.64897
0.79502
0.864362
0.840994
0.844804
0.591566
0.743204
0.8636
0.662686
0.743204
0.71501
0.866902
0.723392
0.771398
0.637286
0.664464
0.619252
0.757682
0.568706
0.734314
0.658622
0.660146
0.699008
Snow (m)
1.2573
1.397
1.03124
1.13284
1.17602
1.01346
1.04394
1.09728
1.3462
1.12522
1.20396
1.143
1.21666
0.97028
1.21158
1.25476
1.10236
1.14554
1.14554
1.17602
1.02362
1.05918
1.07188
1.0541
1.19634
0.9525
1.2446
1.13538
1.22428
0.9906
1.1811
0.92202
1.08712
1.29032
1.13284
1.30048
1.02362
1.75006
1.09474
0.86868
0.88138
1.08966
0.94996
Geopotential Geopotential
rain J y"1 snow J y"1
1.21E+16
2.15E+15
8.84E+15
1.94E+16
2.29E+15
2.35E+15
3.09E+15
2.90E+15
5.41E+15
1.42E+15
1.42E+16
2.49E+15
2.20E+15
3.54E+15
7.00E+15
3.99E+15
4.47E+15
6.79E+15
3.28E+15
2.69E+15
3.76E+15
4.36E+15
5.61E+15
5.20E+15
3.80E+15
2.25E+15
2.72E+15
4.25E+15
6.29E+15
2.32E+15
1.83E+16
2.87E+15
2.60E+15
5.31E+15
5.47E+15
1.67E+16
3.37E+15
1.44E+16
7.16E+15
1.90E+15
4.37E+15
3.97E+15
2.61E+15
1.96E+15
3.51E+14
1.37E+15
2.72E+15
3.43E+14
3.58E+14
3.76E+14
4.06E+14
8.68E+14
1.89E+14
2.41E+15
4.25E+14
3.03E+14
5.64E+14
1.15E+15
7.61E+14
6.11E+14
l.OOE+15
4.03E+14
3.52E+14
5.43E+14
5.21E+14
6.18E+14
5.80E+14
4.85E+14
3.33E+14
4.21E+14
5.00E+14
1.09E+15
2.77E+14
2.78E+15
2.67E+14
3.55E+14
8.20E+14
9.07E+14
3.10E+15
5.14E+14
3.27E+15
1.30E+15
1.99E+14
5.25E+14
6.04E+14
3.18E+14
104
-------
Appendix C
Geopotential Geopotential
County
Marshall
Martin
Meeker
Mille Lacs
Morrison
Mower
Murray
Nicollet
Nobles
Norman
Olmsted
Otter Tail
Pennington
Pine
Pipeston
Polk
Pope
Ramsey
Red Lake
Redwood
Renville
Rice
Rock
Roseau
St. Louis
Scott
Sherburne
Sibley
Stearns
Steele
Stevens
Swift
Todd
Traverse
Wabasha
Wadena
Waseca
Washington
Watonwan
Wilkin*
Winona
Wright
Yellow Medicine
Total
Area m2
4698630977
1888303675
1669194728
1763207250
2984896547
1841457265
1864220833
1208112095
1872245749
2271144960
1693241149
5762399797
1601025432
3711343697
1208059486
5177770684
1857126693
440018746
1121525555
2283127128
2556520608
1334689670
1251081616
4346870123
17450352454
953063015
1166340443
1554551332
3598254294
1119117675
1490663610
1948314509
2536083983
1518712372
1421956082
1406695386
1120615012
1095245269
1138170275
1947254233
1660409003
1849874727
1977544953
2.1849E+11
Elev. (m)
307.848
362.712
277.368
332.232
341.376
393.192
509.016
259.08
478.536
268.224
396.24
371.856
344.424
316.992
521.208
335.28
365.76
280.416
316.992
329.184
326.136
286.512
457.2
323.088
432.816
283.464
301.752
310.896
371.856
350.52
347.472
316.992
393.192
307.848
252.984
411.48
350.52
216.408
329.184
234.696
201.168
304.8
377.952
29445.204
Precip. (m)
0.52959
0.796798
0.747522
0.706374
0.668274
0.842772
0.694944
0.753618
0.707898
0.55499
0.798322
0.622808
0.518414
0.791464
0.657098
0.579628
0.629666
0.825754
0.580644
0.683514
0.700278
0.80391
0.706628
0.546354
0.736092
0.741172
0.744982
0.739394
0.719582
0.80391
0.646938
0.70739
0.747776
0.572516
0.849884
0.67183
0.878332
0.809244
0.704342
0.544322
0.837438
0.72009
0.65278
61.849254
Snow (m)
1.00076
1.08966
1.0287
1.05918
1.27
1.11252
1.07442
0.75184
1.01092
0.73914
1.30302
1.20904
0.91694
1.34366
0.86106
1.00838
0.93218
1.32842
1.23444
0.98298
1.10236
1.07442
1.11252
0.92456
1.62814
0.63246
1.15062
1.016
1.17856
1.04394
1.2065
1.0541
1.30302
1.05664
0.96266
1.22682
1.39446
1.02362
1.06172
1.016
0.90424
0.94742
1.06426
96.35236
rain J y"1
6.38E+15
4.77E+15
3.02E+15
3.57E+15
5.66E+15
5.35E+15
5.67E+15
2.13E+15
5.51E+15
2.96E+15
4.57E+15
1.11E+16
2.41E+15
7.89E+15
3.63E+15
8.50E+15
3.70E+15
8.71E+14
1.68E+15
4.46E+15
5.01E+15
2.69E+15
3.47E+15
6.51E+15
4.49E+16
1.83E+15
2.25E+15
3.12E+15
8.21E+15
2.77E+15
2.80E+15
3.77E+15
6.30E+15
2.24E+15
2.73E+15
3.26E+15
2.95E+15
1.69E+15
2.28E+15
2.08E+15
2.51E+15
3.56E+15
4.16E+15
4.58E+17
snow J y"1
1.14E+15
5.86E+14
3.74E+14
4.87E+14
1.02E+15
6.32E+14
8.00E+14
1.85E+14
7.11E+14
3.53E+14
6.86E+14
2.03E+15
3.97E+14
1.24E+15
4.25E+14
1.37E+15
4.97E+14
1.29E+14
3.44E+14
5.80E+14
7.21E+14
3.22E+14
4.99E+14
1.02E+15
9.65E+15
1.34E+14
3.18E+14
3.85E+14
1.24E+15
3.21E+14
4.90E+14
5.11E+14
1.02E+15
3.88E+14
2.72E+14
5.57E+14
4.30E+14
1.90E+14
3.12E+14
3.64E+14
2.37E+14
4.19E+14
6.24E+14
7.22E+16
105
-------
Environmental Accounting Using Emergy: Minnesota
7 Geopotential of Runoff Total 7.21E+16JV1
Rain 2.55E+16 J y'1
Snow 4.67E+16 J y'1
Geopotential energy of runoff (physical energy of streams) = (area)(mean elevation)(runoff)
(density) (gravity)
The annual runoff is a 100 year average. Drainage basin (38) and runoff data (39) were obtained on-
line from the United States Geological Survey and the State of Minnesota.
Assume 8% sublimation (Essery et al. 2003) for snow and that all snow melt runs off; thus 65% of
runoff is from snow melt.
Watershed
(Scanlon, MN)
(St. Louis River)
* Assumed to be the whole Lake
(Crookston, MN)
(Red Lake River)
(Manitou Rapids, MN)
(Rainy River)
St. Paul, MN
(Mississippi River)
Area*
Elevation
Runoff
Density
Gravity
Energy
Superior Drainage
Area
Elevation
Runoff
Density
Gravity
Energy
Area
Elevation
Runoff
Density
Gravity
Energy
Area
Elevation
Runoff
Density
Gravity
Energy
1.61E+10m2
335.6m
0.2423 16 my1
1000 kg m'3
9.81ms-2
1.28E+16 Jy1
Basin
9.61E+10m2
254m
0.078232 my1
1000 kg m-3
9.81ms'2
1.87E+16 Jy1
2.91E+10m2
324m
0.231 my1
1000 kg m-3
9.81ms'2
2.14E+16 Jy1
m2
208.4m
0.1 12 my1
1000 kg m'3
9.81ms'2
1.92E+16 Jy"1
Wave Energy (Lake Superior) 1.55E+16 Jy"1
Assuming deep water waves and data from an offshore buoy (40). Calculation method from Pierson et
al. (1958).
Length of Coastline (41) 3.30E+05 m
Density l.OOE+03 kg m'3
106
-------
Appendix C
Gravity 9.81ms"2
Average Wave Height* 0.57 m
Period, Tmax 4.8 s
Wave length 35.95 m
Phase speed 7.49 m s"1
Group speed 3.74ms"1
9 River Chemical Potential Absorbed 6.44E+12 J y1
Received 9.15E+15 J y"1
River chemical potential energy received = (volume flow)(density)(Gibbs free energy relative to
seawater)
River chemical potential energy absorbed = (volume flow)(density) (Gibbs free energy solutes at river
entry - Gibbs free energy solutes at river egress)
The St. Croix River begins outside state boundaries and flows along the border with Wisconsin
delivering part of the chemical potential energy that it carries to the state.
Total Dissolved solids concentration from the USGS data (42).
Gibbs Free Energy, G = RT/w ln(C2/Cl) = [(8.3143 J/mol/deg)(288 °K)/(18 g/mol H2O)] * In [(1E6 -
S)ppm)/965000]
St. Croix*
Volume flow 3.87E+09 m3/1
Density 1000000 g m"3
Solutes in 106 ppm
Solutes out 131 ppm
Gin 4.73 Jg"1
Gout 4.72 Jg-1
Absorbed 1.29E+13 Jy"1
Received 1.83E+16 Jy'1
*The river flows along the border the state, so the energy was distributed equally between the states on
opposite sides of the river.
10 River Geopotential Absorbed l.SlE+lSJy1
Received 5.09E+15 J y'1
Geopotential energy = (flow vol.)(density)(height entry - height egress)(gravity)
Data on water flow and height of the gauge are from USGS Water Resources Data (42, 43, and 44).
St. Croix
River* Vol. Flow 3.86E+09 m3/yr
Density 1000 kg/m3
Height In 268.8m
(Height at Danbury, MN)
Height Out 189.3m
(Height at Reno, MN)
Gravity 9.81 m/s2
Absorbed 3.01E+15 J/y
Received 1.02E+16J/y
* If the river borders the state half the calculated energy was used
107
-------
Environmental Accounting Using Emergy: Minnesota
11 Nitrogen (Atmospheric Deposition)
Deposition is a 5 year average (77% NH4 and 23% NOX).
2.00E+11 gy1
1.36E+15 Jy1
Area
Rate (45)
Conversion
Total Deposition
Energy per gram
Energy
12 Sulfur (Atmospheric Deposition)
Deposition is a 5 year average.
Area
Rate (45)
Conversion
Total Deposition
Energy per gram
Energy
13 Chlorine, Cl~ (Atmospheric Deposition)
Deposition is a 5 year average.
Area
Rate (45)
Conversion
Total Deposition
Energy per gram
Energy
2.25E+llm2
8.8636 kg ha1 y1
10000 m2 ha1
2.00E+08 kg y1
6789.5 J g'1 (Weast, 1981)
1.36E+15 Jy-1
5.26E+10 g y'1
3.91E+14 J y'1
2.25E+11 Jy
2.33547 kg ha1 y'1
10000 m2 ha1
5.26E+07kgy-1
7429.06 Jg-1 (Weast, 1981)
3.91E+14JV"1
8.81E+09 g y'1
3.26E+13 J y'1
2.25E+llm2
0.3913 kg ha1 y'1
10000 m2 ha1
3700 J g-1 (Weast, 1981)
3.26E+13 J-1
6.99E+17 J y'1
14 Agricultural Products
(amount sold)(energy/unit)
From the 1997 Census of Agriculture. See Appendix B for energy per unit values except as noted.
Hay
Oats
Corn
Mass (dry) (46)
Energy/unit
Energy
Production (46)
Conversion (47)
Mass
Energy/unit
Energy
Production (46)
Conversion (47)
Mass
Energy/unit
Energy
4.57E+12gy'1
18901 Jg-1
8.63E+16 Jy1
1.62E+07buy1
MSlSgbu'1
2.35E+llgy-1
16280 Jg-1
3.82E+15 Jy-1
7.84E+08buy'1
25401 gbu'1
1.99079E+13gy-1
19736 Jg'1
3.93E+17 Jy-1
108
-------
Appendix C
Soybeans
Wheat
Barley
Sunflower
Wool
Honey
Goat's Milk
Flaxseed
Production (46)
Conversion (47)
Mass
Energy/unit
Energy
Production (46)
Conversion (47)
Mass
Energy/unit (48)
Energy
Production (46)
Conversion (47)
Mass
Energy/unit (48)
Energy
Production (46)
Conversion factor
Mass
Energy/unit (48)
Energy
Production (49)
Conversion factor
Mass
Energy/unit
Odumetal. (1987)
Energy
Production (49)
Conversion factor
Mass
Energy/unit (48)
Energy
Production (49)
Conversion factor
Mass
Energy/unit (48)
Energy
Production (46)
Conversion factor
Mass
Energy/unit (48)
Energy
2.34E+08 bu y'1
27216gbu-1
636E+\2gyl
17410 Jg'1
1.11E+17 Jy-1
27216gbu-1
4.06E+12gy-1
14230 Jg'1
5.77E+16Jy'1
2.19E+07buy'1
21772gbu-1
4.77E+llgy-1
14810 Jg-1
7.07E+15 Jy'1
1.06E+08 Ib.y1
454 gib.'1
4.83E+10gy-1
23850 Jg-1
1.15E+15 Jy-1
9.47E+05 Ib. y'1
454 g Ib;1
4.29E+08 g y-1
20934 J g-1
8.99E+12Jy-1
9.3 1E+06 Ib.y1
454 gib.'1
4.22E+09 g y-1
12720 J g-1
5.37E+13 Jy-1
1.37E+05galy'1
3904 g gal.'1
2880 Jg-1
1.54E+12 Jy-1
8.17E+04buy-1
2540 Igbu'1
2.07E+09 g y-1
20590 Jg-1
4.27E+13 Jy-1
109
-------
Environmental Accounting Using Emergy: Minnesota
Potatoes Production (46)
Conversion factor
Mass
Energy/unit (48)
Energy
Sugar Beets Production (46)
Conversion factor
Mass
Energy/unit (50)
Energy
Milk Production (50)
Conversion factor
Mass
Energy/unit (48)
Energy
Eggs Number (49)
Energy/unit
Energy (50g per
egg)
1.89E+07cwty"1
45359 g cwt"1
S.SSE+llgy"1
2990 J g'1
2.56E+15 J'1
907 1 85 g ton"
7.50E+12gy'1
3390 Jg-1
2.54E+16JV"1
4.75E+06 tons y"1
907185 g ton'1
4.31E+12gy'1
2680 Jg'1
1.15E+16 Jy-1
3.27E+09#y'1
2010 Jg-1
3.29E+14 Jy-1
15 Livestock
(annual production mass)(energy/mass)
The amount sold is taken from the 1997 Census of Agriculture (49).
Turkeys
Cows
Hogs/Pigs
# sold (49)
wt (Live) (51)
Energy /unit (48)
Energy
# sold (49)
wt (Live) (51)
Energy /unit (48)
Energy
# sold (49)
wt (Live) (51)
Energy /unit (48)
Energy
Sheep/Lambs # sold (49)
wt (Live) (52)
Energy /unit (48)
Energy
16 Fish Production
(mass)(energy/mass)
Trout, from the 1997 Census of Agriculture.
4.72E+07
11063 g animal"1
8200 J g-1
4.28E+15 Jy"1
8.25E+05
625050 g animal"1
12225 J g-1
6.31E+15 Jy"1
1.29E+07
118388 g animal"1
15742 Jg"1
2.41E+16 Jy"1
1.65E+05
4808 Ig animal"1
27820 J g-1
2.20E+14 Jy"1
3.49E+16 J y'1
All classes, meat and skin
Choice carcass
Fresh carcass
Raw leg, shoulder, arm
1.32E+11JV1
110
-------
Appendix C
17
18
19
20
Mass (49)
Energy/mass (48)
Hydroelectricity (1999)
E.I.A. (53)
Other Renewable (Wind)
Total Renewable Electricity
47,000 Ibs.y'1
453.59 gib'1
6,190 Jg'1
1,034,697,000 kWh y1
1,174,570,000 kWhy'1
2,209,267,000 kWh y1
Net Timber Growth (1990)
See Haugen and Mielke (2002) and web references below.
(vol. forest growth)(density)(G)
G (no moisture, (54J)=20086 J g"1
Forest Growth (55) 4.51E+08 ft3
1.28E+13 cm3
Green wt. 1 g cm"3
Forest growth 1.28E+13 g y"1
G at 50% moisture 10043 J g"1
Timber Harvest (1997)
Reading and Krantz (2002) give data on harvest and waste.
(vol forest growth)(density)(organic fraction)(G)
G=(4.2kcalg-1)(4186Jkcar1)
Forest Harvest 2.85E+08 ft3
8.06E+12 cm3
Dry wt. 0.5 g cm"3
Forest mass 4.03E+12 g y"1
Energy (20% moisture) 16069 J g"1
Waste 1.42E+08ft3
4.10E+15 J y'1
3.72E+15 Jy'1
4.23E+15 Jy'1
7.95E+15 Jy-1
1.28E+17 J yj
6.47E+16 J y'1
4.61E+15 J y
Groundwater Chemical Potential Energy
(vol.)(density)(Gibbs free energy)
Based on the volume of ground water withdrawn in 1995 (56).
G = RT/w ln(C2/Cl) = [(8.3143 J/mol/deg)(288 K)/(18 g/mol)] * In [(1E6 - S)ppm)/965000]
Concentration taken as an average of all groundwater quality data given for the year 2000.
Volume used (56)
Density
Solute cone. (57)
G
9.87E+08 m3 y1
1000000 g m'3
510 ppm
4.67 Jg'1
21 Solid Waste Production (1997)
From the Minnesota Pollution Control Agency (58).
4.55E+12 g y-1
Note
5,019,980 short tons y'1
907185 g ton'1
4.55E+12gy'1
C2 Notes for Table 5 - Annual Production and Use of Nonrenewable Resources in 1997.
Coal, natural gas and oil are not produced in commercial quantities in the state.
Ill
-------
Environmental Accounting Using Emergy: Minnesota
22 Coal Used in the State (59)
Amount
23 Natural Gas Used in the State (60)
Amount
24 Petroleum Used in the State (61)
Amount
5.09E+17 Jy1
1.91E+07 short tons y"1
9.07E+05 g ton"1
2.94E+04 J g'1
3.54E+08 1000ft3
1.1E+09 J 1000ft'3
1.17E+08 Barrels
3.89E+17 Jy
25 Electricity Produced (w/o hydroelectric and wind)
Energy Information Administration (62).
Amount 4.103E+10kWh
26 Electricity Used in the State
Energy Information Administration (63)
Amount
27 Nuclear Electricity Produced in the State
Energy Information Administration (64)
Amount
7.4E+17 J y-1
1.5E+17 J y'1
2.0E+17 J y'1
6.017E+10 kWh
3.89E+16 J y'1
1.082E+10kWh
Mineral Production
Taken from the preliminary estimates of production found in the
US Geological Survey Minerals Yearbook - 2000 (65). Energy per mass from Odum (1996)
except dolomite (Rock et al 2001)).
28 Iron
29 Sand and Gravel
30 Limestone
31 Dolomite
32 Peat
33 Soil Erosion
(farmed area)(erosion rate)(organic fraction)(energy)
Energy /Mass
Energy /Mass
Energy/Mass
Energy /Mass
Energy /Mass
4.79E+07 MT
14.2 Jg1
3.45E+07 MT
6.11E+02 Jg'1
7.35E+06 MT
50 Jg1
3.08E+06 MT
5.00E+01 Jg-1
2.90E+04 MT
2.15E+04 Jg-1
Total
Agricultural lands
4.79E+13 g y'1
6.80E+14 J y'1
3.45E+13 g y'1
2.11E+16 Jy1
7.35E+12 g y-1
3.68E+14 J y'1
3.08E+12 g y'1
1.54E+14 J y'1
2.90E+10 g y'1
6.24E+14 J y'1
9.79E+16 J/y
9.73E+16 J/y
112
-------
Appendix C
The farmed area was taken from the 1997 census of Agriculture (49).
The organic fraction was taken from Odum (1996). Erosion rates from wind and water (66)
and (67) for cropland and pasture. Energy per gram of soil Campbell (1998).
Erosion rate for forests was from personal communication of one of us (Ohrt) with personnel
of the National Resources Conservation Service (WEPP, 2002).
Cropland Area (49)
Erosion rate
Erosion
Organic fraction
Energy
Pastureland Area (68)
Erosion rate
Erosion
Organic fraction
Energy
Forest Land Area (69)
Erosion rate
Erosion
Organic fraction
Energy
2.15E+07acres
7.3 tons acre"1 y"1
1.57E+08tony"1
0.03
9.07E+05 g ton'1
22604 J g'1
9.65E+16Jy1
3.43E+06 acres
0.4 tons acre'1 y"1
1.37E+06tony-1
0.03
9.07E+05 g ton'1
22604 J g'1
8.45E+14 Jy'1
1.65E+07 acres
0.05 tons acre"1 y"1
0.03
9.07E+05 g ton'1
22604 J g-1
5.08E+14JV1
C3. Notes for Table 6 Imports to the Minnesota economy in 1997
34 Tourism 7.20E+09 $
Estimate for 1997 provided by the Minnesota Department of Trade and Economic Development
(70).
35 Electricity Imported
Use - Production
36 Uranium Imported in 2000
2000 price Average (71)
37 Coal
Energy Information Association
Short tons/yr (59)
g/short ton
J/g
12,433,998,000 kWh
60000000 $
0.0204 $/g
2.94E+09 g
4.48E+16 J y'1
2.94E+09 g y'1
5.09E+14 J y'1
1.91E+04
9.07E+05
2.94E+04
113
-------
Environmental Accounting Using Emergy: Minnesota
38 Petroleum 7.45E+17Jy-1
Value is the difference between the production and consumption within the state.
39 Natural Gas 3.89E+17 J y'1
The difference between the production and consumption within the state (60).
40 Imported Minerals
Data from The 1997 Commodity Flow Survey (2).
41 Goods (Materials minus Fuels and Minerals)
1997 Commodity Flow Survey of Minnesota (Table C3.1)
1.06E+22 sej y'1
3.92E+13 g y'1
2.75E+23 sej y'1
42 Goods (Services) w/o fuels and minerals (Table C3.1)
42 Emergy of Services in all Imported Goods
6.63E+10 $ y'1
1.84E+23 sej y'1
Estimated from data on shipments in the 1997 Commodity Flow Survey, US. Census Bureau
(2). This number includes fuels and minerals, but not electricity.
Total In Bound Shipments
Shipments Of Minnesota Origin
Dollar Value Of Imported Goods
Emergy To Money Ratio For The US In 1997
Emergy In The Services Required For Imported Goods
43 Fuels Services (Table 3.6.1)
44 Minerals Services (2)
45 Electricity Services (Table 3.6.1)
46 Pure Services
Base-Nonbase Analysis using data from the U.S. Census Bureau's
1997 Economic Census (72).(See Table C3.2)
47 Immigration (1997)
Assume that the skill level of immigrants to Minnesota is similar to
the skill levels entering the U.S. in 1997 (73).
48 Federal Government
Total Outlay in 1991 (74).
Units
1.31E+11 Sy"1
5.94E+10$y1
7.19E+10$y1
2.56E+12 sej S'1
1.84E+23sejy1
5.51E+09 $ y'1
6.60E+10 $ y'1
6.22E+08 $ y-1
1.62E+10 $ y'1
8223 Ind.
1.13E+21 sej y'1
1.98E+10 $
114
-------
Appendix C
Table C2.1 Detailed Account of the Emergy Imported in Material Inflows.
This table contains detailed data for note 41 above (2).
SCTG
Code
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
43
0
Commodity Class
Live animals and live fish.
Cereal grains
Other agricultural product
Animal feed and products of animal origin
Meat, fish, seafood, and their preparations
Milled grain products and preparations
Other prepared foodstuffs , fats and oils
Alcoholic beverages
Tobacco products
Monumental or building stone
Natural sands
Gravel and crushed stone
Nonmetallic minerals
Metallic ores and concentrates
Coal
Gasoline and aviation turbine fuel
Fuel oils
Coal and petroleum products
Basic chemicals
Pharmaceutical products
Fertilizers
Chemical products and preparations
Plastics and rubber
Logs and other wood in the rough
Wood products
Pulp, newsprint, paper, and paperboard
Paper or paperboard articles
Printed products
Textiles, leather, and articles
Nonmetallic mineral products
Base metal in primary or semi-finished form
Articles of base metal
Machinery
Electronic and other electrical equipment
Motorized and other vehicles
Transportation equipment
Precision instruments and apparatus
Furniture, mattresses, lamps, lighting
Miscellaneous manufactured products
Waste and scrap
Mixed freight
Commodity unknown
Total
Total without fuels and minerals
J org y"1
6.72E+14
1.50E+17
7.91E+15
2.68E+16
6.30E+15
9.46E+15
5.98E+16
1.24E+16
1.31E+14
2.05E+10
1.51E+12
7.09E+12
1.70E+12
2.94E+11
4.79E+17
1.17E+17
7.47E+16
1.28E+17
9.90E+11
5.19E+10
7.31E+11
7.61E+11
1.09E+12
1.09E+15
1.47E+12
2.67E+16
4.98E+15
5.75E+11
2.35E+15
4.11E+12
2.17E+12
8.79E+11
5.01E+11
4.20E+11
8.27E+11
3.14E+10
1.55E+10
1.64E+11
5.26E+11
8.17E+11
4.05E+11
1.80E+11
Emergy
per unit
4.39E+05
1.82E+05
2.33E+05
1.22E+06
3.27E+06
1.82E+05
1.12E+06
5.89E+04
6.50E+05
9.81E+08
1.96E+09
4.91E+08
1.96E+09
2.71E+09
3.92E+04
6.47E+04
6.47E+04
6.47E+04
2.75E+09
2.75E+09
2.99E+09
9.90E+09
2.71E+09
1.96E+04
1.49E+09
1.40E+05
1.67E+05
4.95E+09
7.18E+06
3.09E+09
5.91E+09
5.91E+09
7.76E+09
7.76E+09
7.76E+09
7.76E+09
7.76E+09
2.89E+09
1.61E+09
2.16E+09
6.32E+09
4.26E+09
Units
sej/J
sej/J
sej/J
sej/J
sej/J
sej/J
sej/J
sej/J
sej/J
sej/g
sej/g
sej/g
sej/g
sej/g
sej/J
sej/J
sej/J
sej/J
sej/g
sej/g
sej/g
sej/g
sej/g
sej/J
sej/g
sej/J
sej/J
sej/g
sej/J
sej/g
sej/g
sej/g
sej/g
sej/g
sej/g
sej/g
sej/g
sej/g
sej/g
sej/g
sej/g
sej/g
sej/y
sej/y
Emergy
sej y"1
2.95E+20
2.72E+22
1.87E+21
3.26E+22
2.06E+22
1.72E+21
6.71E+22
7.56E+20
1.09E+20
2.01E+19
2.96E+21
3.48E+21
3.34E+21
8.07E+20
1.88E+22
7.58E+21
8.19E+21
8.32E+21
3.74E+21
1.43E+20
2.19E+21
7.54E+21
3.09E+21
2.15E+19
3.99E+21
3.75E+21
2.37E+21
2.85E+21
1.73E+22
1.29E+22
1.32E+22
5.35E+21
7.99E+21
6.87E+21
1.22E+22
1.09E+21
2.28E+20
5.27E+20
1.37E+21
1.78E+21
2.56E+21
1.31E+21
3.20E+23
2.75E+23
115
-------
Environmental Accounting Using Emergy: Minnesota
Table C2.2 Export and Import of Services Between Minnesota and the Nation
The emergy of imported and exported services was determined using a variation of the base-nonbase method
from economic analysis. Data on employment and revenues for economic sectors classified using the North
American Industry Classification System (NAICS) for MN and the U.S. (75) were used to estimate the services
exported and imported from the state. The formulae in the text are evaluated using data in the table below. The
rows in the table below are (1) U.S. employment by sector, (2) Minnesota employment by sector, (3) the fraction
of total U.S. employment in each sector, (4) the fraction of total state employment in each sector. Row (5) and
(6) give the money received per paid employee in the nation and state, respectively. Row (7) is the location
quotient, i.e., row 4 divided by row 3, while (8) is the number of employees, Sl5 in each state sector (row 2)
divided by the number of employees, Ni; (row 1) in the corresponding national sector. Row (9) is the sum of
state employees in all sectors divided by sum of employees in all sectors of the national economy. Row (10)
calculates basic sector jobs as the difference between rows (8) and (9) times the U.S. employment in each sector,
and (11) estimates the dollar value of potential exports by multiplying the state dollars generated per employee
by the number of basic employees (row 10) that could be making products or services for export. We extend this
calculation to potential imports by multiplying any deficient in employment in row 10 by the dollars generated
per employee in that sector of the national economy.
Parameters Agricult. Mining
Economic Sectors
Utilities Construct. Manufact.
Wholesale Retail trade Transport. Informal.
U.S. Employees
MN Employees
US (sector /total)
MN (sector/total)
$/employee US
$/employee MN
Location Quotient
(Si) "-(NO
(StK(Nt)
Basic jobs (B)
Potential Imp./Exp.
Exp(+) or imp(-) $*
Services in Sector
Assumed type
3085992
101593
0.0249
0.0414
63793
81603
1.6621
0.0329
0.0231
30246
2.47E+09
O.OOE+00
All goods
Basic
509006
7154
0.0041
0.0029
341840
243130
0.7096
0.0141
0.0231
-4614
-1.58E+09
-1.35E+09
Imported
Basic
702703
13205
0.0057
0.0054
585899
336321
0.9487
0.0188
0.0231
-3041
-1.78E+09
O.OOE+00
Local
Nonbasic
5664840
103200
0.0457
0.0420
151563
179574
0.9198
0.0182
0.0231
-27769
-4.21E+09
O.OOE+00
Local
Nonbasic
16888016
382530
0.1362
0.1558
227502
199317
1.1436
0.0227
0.0231
-7914
-1.58E+09
O.OOE+00
All goods
Basic
5796557
131787
0.0468
0.0537
700357
754585
1.1478
0.0227
0.0231
-2227
-1.68E+09
O.OOE+00
Local
Nonbasic
13991103
282413
0.1128
0.1150
175889
170311
1.0191
0.0202
0.0231
-41056
-6.99E+09
O.OOE+00
Local
Nonbasic
2920777
53811
0.0236
0.0219
108959
1052356
0.9301
0.0184
0.0231
-13716
-1.49E+09
O.OOE+00
Local
Nonbasic
3066167
58855
0.0247
0.0240
203255
164138
0.9691
0.0192
0.0231
-12034
-2.45E+09
-1.22E+09
Imported
Basic
* We assume that only basic sectors can export. Some of the potential export and import sectors summed here are
only part service at this level of sector aggregation. Subtracting the dollar value of the goods exported in the
sector from total estimated exports may give a better estimate of the services exported. An alternate method
considers higher resolution sector data where more detailed sectors can be identified as primarily service.
Considering higher resolution data the fraction of potential service imports was estimated, but a full analysis using
this method was not used here.
116
-------
Appendix C
Economic Sectors continued:
U.S. Employees
MN Employees
US (sector /total)
MN (sector/total)
$/employee US
$/employee MN
Location Quotient
(SO •*• (NO
(SO •*• (NO
Basic jobs (B)
Potential
Imp./Exp.
Exp(+) imp(-)$#
Services in Sector
Assumptions
Finance& Real Estate/
Insurance Rental
5835214
65996
0.0471
0.0269
376639
262568
0.5710
0.0113
0.0231
-10081
-1.40E+09
-7.00E+08
Imported
Basic
1702420
30172
0.0137
0.0123
141515
128809
0.8948
0.0177
0.0231
-9187
-1.30E+09
O.OOE+00
Local
Nonbasic
Profession.
Scientific
5361210
97818
0.0432
0.0398
111029
108001
0.9212
0.0182
0.0231
-26131
-2.90E+09
-1.45E+09
Imported
Basic
Admin.
Managem. Support
2617527
86754
0.0211
0.0353
35328
49107
1.6733
0.0331
0.0231
26238
1.29E+09
1.29E+09
Exported
Basic
7347366
133839
0.0593
0.0545
40278
39132
0.9197
0.0182
0.0231
-36006
-1.45E+09
O.OOE+00
Local
Nonbasic
Education HealthCare Arts&
Services Social Ser. Entertain.
321073
6064
0.0026
0.0025
63659
63249
0.9535
0.0189
0.0231
-1359
-8.65E+07
-4.33E+07
Imported
Basic
13561579
298312
0.1094
0.1215
65262
56416
1.1106
0.0220
0.0231
-15226
-8.59E+08
O.OOE+00
Local
Nonbasic
1587660
37343
0.0128
0.0152
65956
52030
1.1875
0.0235
0.0231
637
3.31E+07
3.31E+07
Exported
Basic
Accomo.
&Food
9451226
179487
0.0762
0.0731
37074
33062
0.9588
0.0190
0.0231
-39022
-1.45E+09
O.OOE+00
Local
Nonbasic
Economic Sectors
U.S. Employees
MN Employees
US (sector /total)
MN (sector/total)
$/employee US
$/employee MN
Location Quotient
(SO •*• (NO
(SO •*• (Nt)
Basic jobs (B)
Potential Imp./Exp.
Exp(+) imp(-)$*
Services in Sector
Assumptions
Total Employment
Total Employment
continued:
Other Ser.
3256178
77235
0.0263
0.0315
81659
71947
1.0194
0.0237
0.0231
1953
1.41E+08
3.51E+07
Local
Nonbasic
U.S
Minnesota
Auxiliary
792370
13734
0.0064
0.0056
14231
4650
0.7449
0.0173
0.0231
-4585
-6.53E+07
-1.63E+07
Imported
Nonbasic
107,274,984
2,480,156
Govern.
19521000
294388
0.1576
0.1199
42453
26899
5.1086
0.1189
0.0231
194895
8.27E+09
O.OOE+00
Local
Nonbasic
Table C2.3 Determination of Imported and Exported Services
Potential for Importing ($) 8.39E+09
Estimate of Imported Ser. ($) 4.22E+09
Multiply deficit employment times U.S. worker productivity
in sectors assumed to be capable of importing services and
sum over the sectors.
Use detailed NAICS categories; determine a fraction of
potential imports that is non local service. Assume MN
imports everything that they need
Estimate of Exported Ser ($) 1.36E+09 The sum of basic exporting sectors in Table C3.2 above.
117
-------
Environmental Accounting Using Emergy: Minnesota
Emergy exported services 3.47E+21
(sej y"1)
Emergy imported services 1.08E+22
(sej y1)
Multiply the exports in dollars by the emergy to dollar ratio
of the U.S. in 1997 to estimate the emergy exported
Multiply the dollar value of the imported services times the
emergy to dollar ratio of the U.S. in 1997.
C4. Notes for Table 7 - Exports from the Minnesota Economy in 1997.
49 Materials in Goods Exported Minus Fuels and Taconite
Data from Commodity Flow Survey of Minnesota (2).See Table C4.1 for totals.
50
Taconite Exported (2)
Total Shipments
Instate Shipments
Exported
4.30E+13 g
7.25E+12 g
3.58E+13g
3.85E+23 sej y'1
3.58E+13 g
51
Services in Goods Exported.
Data on shipments from the 1997 Commodity Flow Survey (2).
Emergy to dollar ratio for the US in 1997
Dollar value of shipments to all destinations
Dollar value final destinations in MN
Dollar value of exported goods w/o iron
Emergy exported in services in goods w/o iron
Value of exported metallic ores
Total value shipments (2)
Fraction leaving the state
Dollar value metallic mineral exports
Emergy in services associated with iron export
Total value of services in exported goods
Units
2.56E+12 sej/$
1.55E+11 $/y
5.94E+10 $/y
9.46E+10 $/y
2.42E+23 sej y'1
1.44E+09 $
0.83
1.20E+09$/y
3.06E+21 sej y'1
2.45E+23 sej y'1
Table C3.1 Emergy in the materials exported from Minnesota. Data on material shipments from Minnesota to all
states by commodity is from The U.S. Census Bureau's 1997 Commodity Flow Survey (2), Additional State Data, Table
12. In some cases in Table C4.1 shipment weight was converted to energy. See Appendix B for the calculation of average
emergy per unit for the commodity classes and a table giving the mass to energy conversions for the commodity class.
SCTG Emergy Emergy
Code Commodity Class
Jorg
per unit
Units
sej y"
1
2
3
4
5
6
7
8
9
10
11
Live animals and live fish.
Cereal grains.
Other agricultural product.
Animal feed and products of animal origin.
Meat, fish, seafood, and their preparations.
Milled grain products and preparations.
Other prepared foodstuffs and fats and oils.
Alcoholic beverages.
Tobacco products.
Monumental or building stone
Natural sands
0
2.55E+17
4.61E+16
2.26E+16
1.10E+16
2.62E+16
1.05E+17
4.90E+15
1.06E+14
0
1.21E+12
4.393E+05
1.818E+05
2.334E+05
1.217E+06
3.270E+06
1.818E+05
1.120E+06
5.886E+04
6.500E+05
9.810E+08
1.962E+09
sej r1
sej r1
sej r1
sej J'1
sej r1
sej I'1
sej r1
sej r1
sej r1
sej g'1
sej g"1
0
4.63E+22
1.08E+22
2.75E+22
3.61E+22
4.76E+21
1.17E+23
2.88E+20
6.91E+19
0
2.37E+21
118
-------
Appendix C
Table C3.1 continued
12 Gravel and crushed stone
13 Nonmetallic minerals
14 Metallic ores and concentrates
15 Coal
17 Gasoline and aviation turbine fuel
18 Fuel oils
19 Coal and petroleum products
20 Basic chemicals
21 Pharmaceutical products
22 Fertilizers
23 Chemical products and preparations
24 Plastics and rubber
25 Logs and other wood in the rough
26 Wood products
27 Pulp, newsprint, paper, and paperboard
28 Paper or paperboard articles
29 Printed products
30 Textiles, leather, and articles
31 Nonmetallic mineral products
32 Base metal primary or semi-finished form
33 Articles of base metal
34 Machinery
35 Electronic and other electrical equipment
36 Motorized and other vehicles
37 Transportation equipment
38 Precision instruments and apparatus
39 Furniture, mattresses, lamps, lighting
40 Miscellaneous manufactured products
41 Waste and scrap
43 Mixed freight
0 Commodity unknown
Natural Gas (joules)
Total
Total without fuels (15,17,18, natural gas)
Exported fuels
Total without fuels and iron ore
6.14E+12
0
3.57E+13
1.60E+15
8.38E+16
6.80E+16
2.58E+17
1.04E+12
8.71E+10
5.72E+11
7.72E+11
6.90E+11
0
2.07E+12
3.08E+16
5.17E+15
8.99E+11
3.85E+15
4.73E+12
3.29E+12
8.24E+11
4.65E+11
3.85E+10
7.82E+11
5.26E+10
6.44E+10
1.70E+11
8.13E+11
3.18E+12
1.32E+12
1.38E+11
0
4.905E+08
1.962E+09
3.61E+09
3.78E+04
6.475E+04
6.475E+04
6.475E+04
2.750E+09
2.750E+09
2.993E+09
9.902E+09
2.709E+09
1.962E+04
1.490E+09
1.398E+05
1.674E+05
4.951E+09
7.177E+06
3.094E+09
5.906E+09
5.906E+09
1.47E+10
1.47E+10
1.47E+10
1.47E+10
1.47E+10
2.890E+09
1.613E+09
2.161E+09
6.316E+09
5.710E+09
4.80E+04
sej g'1
sej g'1
sej g'1
sej I'1
sej J'1
sej I'1
sej J'1
sej g'1
sej g'1
sej g'1
sej g'1
sej g'1
sej J'1
sej g'1
sej J'1
sej I'1
sej g'1
sej I'1
sej g'1
sej g'1
sej g'1
sej g'1
sej g'1
sej g'1
sej g"1
sej g'1
sej g"1
sej g'1
sej g"1
sej g'1
sej g'1
sej/J
3.01E+21
0
1.29E+23
6.07E+19
5.43E+21
4.40E+21
1.67E+22
2.86E+21
2.39E+20
1.71E+21
7.64E+21
1.87E+21
0
3.08E+21
4.31E+21
8.66E+20
4.45E+21
2.77E+22
1.46E+22
1.94E+22
4.86E+21
6.84E+21
5.65E+21
1.15E+22
7.73E+20
9.47E+20
4.90E+20
1.31E+21
6.87E+21
8.35E+21
7.87E+20
0
5.41E+23
5.15E+23
2.66E+22
3.85E+23
119
-------
Environmental Accounting Using Emergy: Minnesota
52 Pure Service Exported at the U.S. Em/$ Ratio
3.47E+21 sej y'1
1.36E+09S
53 Federal Government
Taxes 1997 (76).
54 Tourists (experiences taken home)
Money spent
Emergy purchased
2.60E+10 $
7.2E+09 $
3.352E+22 sej y"1
A rough approximation of the experiences taken home by tourists is the dollars spent in
recreation times the emergy to money ratio of Minnesota in the year of their visit.
C5. Notes for Table 8 - Value of Minnesota Storages in 1997.
55 Forest Storage
Based on the forest inventory for Minnesota in Haugen and
Mielke (2002)
Timberland Standing Mass
56 Water (Lakes)
Total Volume (77)
Density
Concentration (78)
Gibbs
4.29E+6 Tons dry wt.
3.895E+15 g
16069 Jg'1
1.43E+llm3
1000000 g/m3
7.9 ppm
4.74 J/g
57 Water (Minnesota Part of Lake Superior)
Chemical Potential
6.26E+18 J
6.76E+17 J
3.30E+17 J
Total Volume (79)
% of Shoreline in MN
Density
Solute Concentration (80)
Gibbs
Energy Stored in The Lake
Turnover Time
Net Volume Water per Year
Gibbs Free Energy at 5 ppm
Energy Inflow per Year
Transformity Chemical Potential Of Rain
Emergy Input per Year
Emergy to Support Storage
Transformity Lake Superior Water
58 Soil (Organic Matter)
Soil Org M. In The Upper 1m*
Average Calories In Soil OM
Low
1.88E+15
5.04
1.22E+13m3
0.0755 Dimensionless
1000000 g/m3
63 ppm
4.73 J/g
4.37E+18 J
191 y
6.41E+10m3
4.74 J/g
3.04E+17J/y
1.81E+04sej/J
5.49E+21 sej/y
1.05E+24sej
2.40E+05 sej/J
High
8.10E+15
Mean
4.46E+15
Units
kcal g"
120
-------
Appendix C
Energy in Soil Organic Matter 21097 J/g
Energy of Stored OM In Soils 3.96E+19 1.71E+20 9.42E+19 J
Transformity of Topsoil 7.26E+04 sej/J
Emergy Stored In Soils 2.87E+24 1.24E+25 6.84E+24 sej
Soil organic matter estimates were made by Denis White of the Office of Research and Development
Western Ecology Division with the assistance of Jeff Kern of Dynamic Corporation. The formula given
below was used for the calculation of OM in each horizon (or layer in STATSGO) in each component
of each map unit (USDA 1994):
Layer OM = Depth * Bulk Density * Proportion Organic Matter * Proportion Not.Rock
The variable called "proportion.not.rock" (Tan et al. 2004) was computed from seven STATSGO
variables. The script used for the mean value computation was written in R by Denis White. The results
above were derived using the low values of bulk density (bdl) and organic matter (oml) for each layer
and also the high values (bdh and omh), The mean values are taken as our best estimate for this study.
Mineral Reserves
59 Iron (81) 1.40E+10MT 1.40E+16 g
Energy/Mass 14.2 J/g 1.98E+17 J
60 Sand & Gravel Short tons 3.19E+16 g
(construction) 3.51E+10
6.11E+02J/g 2.15E+19J
Estimate based reserves in a seven county metro area (82) prorated to areas of the state where the
Minnesota Department of Natural Resources is assessing the sand and gravel resource (83). We
assume the maximum value for the reserves.
61 Limestone 2.82E+09 MT 2.82E+15 g
Energy/Mass 50 J/g 1.41E+17 J
Based on the projected reserves of Vetter Stone Co. in Kasota, MN and present production rate
62 Dolomite 1.32E+08 MT 1.32E+14 g
Energy/Mass 11635.6 J/g 1.54E+18 J
Assumes dolomite has the same projected resources as limestone.
63 Copper* 4.50E+09 MT 4.50E+15 g
Energy/Mass l.OOE+06 g/moon
64 Nickel* 4.50E+09 MT 4.50E+15 g
Energy/Mass l.OOE+06 g/moon
* There is a Copper/Nickel complex of 4.5 billion tons of ore, according to Ojakangas and Matsch
1982. Assume that Ni and Cu are by-products. Ore grade is given at (84).
121
-------
Environmental Accounting Using Emergy: Minnesota
Minnesota Nickel, Copper and Platinum ore relative to Cohen etal. (2007) OGC.
Element
Copper
Nickel
Platinum
Concentration %
0.694
0.218
5.73E-05
Ore Grade Cutoff %
Cohen et al. (2007)
0.35
1.0
1.1E-04
Transformity
adjustment
1.983
0.218
0.521
65 Peat 3.52E+09 MT 3.52E+15 g
Energy/Mass 2.15E+04J/g 7.57E+19 J
Estimate based on Minnesota Department of Natural Resources estimate of peat lands (85) and the dry weight
and area of peat lands in Aiken county, which is about 7% of the total resource.
66 Platinum
Platinum (PtEq) 3.20E+07 short tons 2.90E+13 g
67 People 1.41E+24 sej
Using the population percentages from the 2000 Census (86).
1997 Population (Estimate) 4735830 people
Number of individuals
Preschool
School
College Grad
Post-College
Public Status*
Legacy*
2000
329605
2402204
1882631
255844
49195
765
Fraction
6.70%
48.83%
38.27%
5.20%
1.00%
1997
317301
2312528
1812350
246293
47358
765
sej/ind.
3.34E+16
9.22E+16
2.75E+17
1.29E+18
3.86E+18
7.70E+18
sej
1.06E+22
2.13E+23
4.98E+23
3.17E+23
3.65E+23
5.89E+21
Total 4919479 100% 4735830 1.41E+24
*Public Status is estimated as one per cent of total population.
All individuals listed in the index to Minnesota: A History of the State by Theodore C. Blegen
are counted as part of Minnesota's legacy.
A few of those legacy individuals are:
Ignatius Donnelly - Minnesotan congressman
F. Scott Fitzgerald - Author
Alexander Ramsey - First governor
Dr. Archibald Graham - Author, "Shoeless Joe" (Field of Dreams)
Walter Mondale - Politician
Hubert Humphrey - Presidential Candidate, Vice President
122
-------
Appendix C
C6. Notes for Table 9- Summary Flows for Minnesota in 1997
68 The largest renewable emergy sources are the wind energy absorbed in the planetary boundary layer, the
wave energy absorbed on the shore of Lake Superior and the geo- and chemical- potential energy
delivered to the state in the St. Croix River.
69 Electricity from renewable sources includes wind, hydropower, and other renewable sources. This
renewable class of energy was added for this study. It represents the amount of energy for concentrated
use that has been extracted from the renwebale emergy base o fthe system.
70 Nonrenewable sources (Table 5) include fuels and minerals coal, natural gas, petroleum, sand and gravel,
limestone dolomite, iron ore and soil erosion where it exceeds soil building, i.e., in agricultural areas.
71 Extracted fuels and minerals from within the state. This flow was used in the West Virginia study but it
was given a symbol that was inconsistent with past usage. Here it has been designated uniquely by adding
a prime to Nl.
72 Dispersed Rural Source (Table 5) is the soil erosion in agricultural areas. This category includes any
renewable resource that is being used more rapidly then it is being replaced.
73 Concentrated Use is the emergy in the mined tonnage of fuels and minerals used within the state plus the
emergy of electricity, from nuclear, hydropower, wind and other nonfossil fuel and internal renewable
sources.
74 Fuels and minerals exported without use are the quantities of iron ore exported directly and as taconite. In
the case of taconite pellets some value is added to the Minnesota economy before export; however, this
value is relatively small compared to the wealth generating potential of the ore when used in steel-making.
75 Imported fuels are coal, petroleum, natural gas and uranium plus some minerals (Table 6).
76 Fuels and minerals used. Add mineral production and fuel and mineral imports and subtract minerals
exported without use.
77 In state minerals used: Subtract minerals exported without use from mineral production.
78 The material imported in goods was determined from the 1997 Commodity Flow Survey by summing the
tonnage by commodity class from states with significant exports to Minnesota. (Table C3.1).
79 Dollars paid for imports is the sum of the dollar value of imported goods including fuels and minerals and
all other goods and services.
80 The services in imported fuels and minerals and electricity are determined below.
Table C4.1 Services in Imported Fuels and Minerals
Fuel Quantity Unit Price ($/Unit) $ y"1
Coal
Petroleum
Natural Gas
Electricity
Uranium
1.91E+07
4.92E+09
3.54E+08
l.E+10
6.49E+6
short tons
gallons
1000 cu-ft
kWh
Lb.
26.64
0.8
3
0.05
9.25
5.08E+08
3.94E+09
1.06E+09
6.22E+08
6.00E+07
The prices of these items can be found in the data sources given in Campbell et al. (2005)
81 Dollars paid for goods without fuels and minerals is the total dollar value of goods imported from the CFS
minus the dollar value in fuels and minerals calculated above.
82 Dollars paid for imported services as determined using the base-nonbase method (Table C3.3).
83 Dollars spent by tourists in the State of Minnesota, in 1997 or 2000
84 Federal transfer payments are the total outlay of funds in MN by the Federal government.
85 Imported Services Total is the sum of the emergy in services associated with imported goods, fuels, and
minerals, and pure services.
86 Imported Services in fuels and minerals is the emergy equivalent of the human service represented by the
money paid for fuels and minerals. Dollars are converted to emergy using the 1997 emergy/$ ratio for US.
123
-------
Environmental Accounting Using Emergy: Minnesota
87 Imported Services in Goods is the emergy equivalent of the money paid for goods minus that paid for
fuels and minerals.
88 Imported Service is the emergy equivalent of the money paid for services again assuming an average
emergy backing a dollar spent for human service in a given year.
89 Emergy Purchased by Tourists is the emergy purchased when tourists $ are spent in Minnesota, i.e., at
Minnesota's emergy to dollar ratio.
90 Net Emergy purchased by Federal dollars spent in the state. Use Minnesota emergy/$ ratio and the
difference between outlays and taxes. A negative number shows the emergy flow forgone by failure to
spend tax dollars in the state.
91 Exported Products is the emergy in the goods exported including electricity, excluding iron ore.
92 Dollars Paid For All Exports. This is the sum of the money paid for goods, iron ore and services.
93 Dollars Paid for Services in Goods. This is the money paid for products listed in 88 above.
94 Dollars Paid for Services in Iron. This is the money paid for taconite exported..
95 Dollars Paid for Services. This is the money paid for pure services supplied by Minnesota to the rest of the
nation as determined by the Base-Nonbase method.
96 Federal Taxes Paid is the sum of personal income, social security, and business taxes
97 Total Exported Services is the sum of the emergy equivalents in human service in fuels, goods and
services exported.
Table C4.2 Services in Exported Minerals
Amount 1997 prices $/Ton. $
Taconite Pellets 3.94E+07 36.50 1.2E+09
98 Exported Services in Goods. This is the emergy equivalent of the dollar value of all exported goods
excluding taconite. It is determined by multiplying the dollars paid for goods by the emergy to money ratio
for the U.S. in 1997 or 2000. In using P2 to determine services, our implicit assumption is that the emergy of
human service in Minnesota is not much different from the average for the U.S.
99 Exported Services in iron is the emergy equivalent of the human service in the dollars paid for taconite
pellets exported. Service is determined using the US emergy/$ ratio for 1997 or 2000 under the assumption
given in 98 above.
100 Exported service is the emergy equivalent of the dollar value of exported pure services. This number was
determined as in 98 and 99 above.
101 Gross State Product (87) for Minnesota in 1997 or 2000.
102 Emergy-to-dollar ratio for the U.S. in 1997 and in 2000(sej/$).
103 Emergy-to-dollar ratio for the State of Minnesota in 1997 and in 2000 (sej/$).
C7. Notes for Table 10. Calculation of Emergy Indices
104 Renewable Emergy Used (see Note 68).
105 In-State Nonrenewable Use is the sum of dispersed rural sources (No) and in-state mineral production.
106 Imported Emergy is the sum of imported fuels and minerals (F), goods (G), and services (PI).
107 Total Emergy Inflow is the sum of renewable emergy absorbed (RA), and the emergy imported in the
previous note.
108 The total emergy used in the state (U) is the sum of the renewable emergy absorbed (RA), the emergy used
from dispersed rural sources (N0), fuels and minerals used (Fj), and the goods (G) and services (PI)
imported.
124
-------
Appendix C
109 Total exported emergy is the sum of the emergy in the materials of exported goods (B), the emergy of
services associated with goods and with pure service (PE) and the emergy of fuels and minerals exported
without use (N2).
110 The emergy used from home sources is the sum of emergy from dispersed rural sources, in-state minerals
and fuels used (F2), and renewable emergy absorbed divided by total use (U).
Ill Import minus export is the difference between imported emergy and exported emergy.
112 Ratio of exports to imports is the quotient of the expression in Note 109 divided by the expression in Note
106.
113 Fraction of use that is locally renewable is the ratio of renewable emergy absorbed to total use.
114 Fraction of use that is purchased is the ratio of imported emergy to total use.
115 Fraction of use in imported service is PI divided by U.
116 Fraction of use that is free is the sum of the renewable emergy absorbed and emergy from dispersed rural
sources divided by total use.
117 Ratio of purchased to free is the quotient of the sum of imported fuels and minerals (Fi), imported goods
(G) and imported services (PI) divided by the sum of the renewable emergy absorbed (RA) and the emergy
from dispersed rural sources (N0).
118 Environmental loading ratio is the quotient of the sum of the emergy from dispersed rural sources (No),
imported fuels and minerals (Fi), imported goods (G) and imported services (PI) divided by the renewable
emergy absorbed (RA).
119 Investment Ratio. There are several possible investment ratios (Odum 1996). This one compares imported
emergy to the emergy supplied form within the state. The emergy from within the state is the sum of the
renewable emergy absorbed (RA), the emergy from dispersed rural sources (N0), and the emergy from in-
state fuels and minerals (F2).
120 Emergy use per unit area (Empower density) is the total emergy use (U) divided by the area.
121 Use per person is the total emergy U divided by the population.
122 Renewable carrying capacity at the present standard of living is found by dividing the renewable emergy
received by total use and then multiplying this fraction times the present population.
123 Developed carrying capacity at the present standard of living is approximately eight times the renewable
carrying capacity.
124 Minnesota State Economic Product (87) in 1997 or 2000.
125 Ratio of Minnesota emergy use to GSP. Divide U by X, the GDP.
126 Ratio of U.S. Emergy use to GNP. See Appendix B4.2.
127 Ratio of emergy in electricity use to total use (El/U). See Table 5 for electricity use.
128 Ratio of electricity production to total use (Elp/U).). See Table 5 for electricity production.
129 Fuel use per person is the sum of coal, natural gas, and petroleum used in the state divided by population.
130 Population of the State (86) in 1997 and in 2000
131 Area of the State (24)
132 Renewable Empower Density is the emergy flow of renewable energy per unit area.
125
-------
Environmental Accounting Using Emergy: Minnesota
Appendix D
Calculating the Import and Export of Materials
126
-------
Appendix D
Dl. Creating Export/Import Spreadsheets for
Materials
The method used to determine the emergy exported
from and imported to a state was further developed in
this study to take advantage of the extensive data on this
subject provided by the U.S. Census Bureau's
Commodity Flow Survey (2), which is performed every
five years. This innovation resulted in a marked
improvement in the accuracy with which imports and to
a lesser extent exports from a state's economy can be
determined. Even though the CFS provides all the
information needed to document exports and imports it
is not tabulated in the form that we need and some of the
information is hidden rather deeply in the data base. To
make our method transparent and reproducible, we have
described in detail the characteristics of the database,
data sources and methods that we used to determine the
emergy imported and exported from Minnesota. These
methods should be applicable to the determination of
imports and exports for any other state and to regions, if
data at that level can be obtained. To facilitate following
the method described below the appropriate tables from
the CFS should be referred to when needed. If the data
tables or presentation of information change in the
future these instructions will have to be altered.
Export Calculations
Determining material and energy flows for exports is
straightforward with few extrapolations or assumptions
needed, because the data are relatively complete as
provided in the CFS. Data on dollar value and tonnage
of export shipments between states by commodity class
comes from the Commodity Flow Survey (CFS), Table
12 (Additional State Data). This data is also summarized
in Tables 5, 7, and 8 in the CFS report on each state.
The CFS uses several data codes when a numeric
measurement is not given and these codes were handled
in a consistent manner. For example, most states have an
S or a D in one or more data fields for some commodity
shipments. These letters indicate variable data (S) or a
single source of information (D) that would risk
disclosure of the data source, if reported. In the export
calculation method, no estimate of exports was made for
commodity classes with and S or D in both the $ value
and tonnage columns for instate shipments. When this
occurs there is often an S or a D in the "all destinations"
category, as well. In this case there are too many
unknowns to make an estimate. Materials moving in
these classes were assumed to remain within the state or
to constitute a negligible fraction of exports.
Commodities with a dollar value but no information on
tonnage were retained in the data because the tonnage
could be reasonably estimated using the price per ton
obtained from the dollar value and tonnage of the
commodity going to all destinations.
Before transferring data from Table 12 to an interim
spreadsheet, all dashes (indicating no data) were
replaced with zeroes. If there was evidence that some
flows were not actually zero, remain uncounted, or are
different from the estimates provided, additional
information was added when the emergy exported in
each commodity class was determined. For example,
coal exports were determined using Energy Information
Administration (EIA) Data (6). The Commodity Flow
Survey provides a summary table (Table 7) of shipments
to all states from the state of origin. Note that the top
row in this table gives the total dollar value and tonnage
of shipments from the state followed by a set of rows for
dollar value and tonnage shipments to each state to
which the state of origin is shipping. This includes a
row for the state of origin itself, which will be referred
to as instate shipments from now on.
The commodity classes for Standard classification of
Transported goods (SCTG), Standard Industrial
Classification (SIC), and the North America Industry
Classification System (NAICS) industry classification
codes and the approximate conversions used in this
paper are shown in Table Dl. An export table (see Table
D2) with 11 columns was made to use in determining
the tonnage exported in various commodity classes. The
column headings for the export table are as follows (1)
SCTG code, (2) Description of the class, (3) All
Destinations Value($ mil), (4) All Destinations
Tons(OOO) (5) $/Ton, (6) Instate Shipments ($ mil), (7)
Instate Shipments Tons(OOO), (8) Known (directly
measured) exports Tons(OOO), (9) Instate Tons (000)
estimated using $/T, (10) Estimated exports tons (000),
(11) Final Exports (estimated exports are adjusted to
sum to the total missing tonnage).Table D2 omits
column 2, the verbal description, because of space
considerations.
127
-------
Environmental Accounting Using Emergy: Minnesota
Table Dl Approximate conversion between SCTG , SIC and NAICS industry classification codes developed
for this study. These conversions are only approximate and better information might be
developed of used if available.
Class Combined Code SCTG code SIC code NAICS Code
Agricultural products, grain
Livestock, seafood, animal products
Logs, rough wood
Metallic ores
Coal
Non-metallic minerals, gravel, stone,
sand
Prepared food products, alcohol,
tobacco
Textiles, leather, apparel
Lumber wood product
Furniture, fixtures
Paper products
Printed products
Chemicals
Refined petroleum products
Plastics and rubber
Building materials, non-metallic
Primary metal products, semi-finished
Fabricated metal products. Cans etc.
Machinery (not electrical)
Electrical equipment, precision
instruments
Transportation equipment
Miscellaneous manufactured goods
Scrap and waste
Unknown, mixed or special classes
A
B
C
D
E
F
G
H
I
J
K
L
M
N
O
P
Q
R
S
T
U
V
w
Y
2,3
1,4
25
14
15
11,12,13
5,6,7,8,9
30
26
39
27,28
29
20,21,22,23
17,18,19
24
10,31
32
33
34
35.38
36,37
40
41
43
1
2,9
8
10
12
14
20,21
22,23,31
24
25
26
27
28
29
30
32
33
34
35
36,38
37
39
49
92,98,99
111
112
113
2122
2121
2123
311,312
313
321
337
322
323
325
324
326
327,331
331
332
333
334,335
336
339
562
99999
The steps in estimating exports from a state, e.g., Minnesota, using the data in the spreadsheet columns described
above are as follows:
First, copy the Commodity Class code and description from the Commodity Flow Survey Table 12 (Additional
Data) for the state, for which exports are to be calculated Columns (1 and 2). Remember in following the
instructions below that column numbers refer to the 11 column headings recommended above. The 10 columns
shown in Table D2, which is missing column 2, have been numbered to match the verbal description.
1. Copy the $ value and tons moving from the state to all destinations for all commodities, Columns (3) and (4).
2. Calculate or otherwise determine the $ per ton. Column (5)
3. Copy data ($ and Tonnage) for shipments of all commodities with final destination in the state of origin, e.g.,
from MN to MN, Columns (6) and (7).
4 Calculate known exports by subtracting instate shipments (column 7) from the shipments moving to all
destinations (column 4) for all commodities for which tonnage has been measured, directly, Column (8).
5. Sum the tonnage of directly measured export shipments (Column 8) and subtract from the total tonnage moving
to all destinations. The total tonnage is given at the top of the All Destinations column in Table D2 and in CFS
Table 12.
128
-------
Appendix D
6. Calculate the tonnage of instate shipments for any commodity for which a $ value of instate shipments is given
in column 6 by dividing by the $ per ton (column 5). Record in Column 9 the estimated instate shipments.
7 Estimate the tonnage exported in these commodity classes by subtracting the instate tonnage estimates (column
9) from tonnage moving to all destinations (column 4). Record these estimates in Column 10.
8. Sum the estimated export shipments (column 9) and divide into the difference between directly measured
exports and total exports. If this ratio equals 1 combine directly measured and estimated exports in their
respective commodity classes into a single column (11) and you are done. If greater or less than 1 multiply each
estimated commodity by this ratio to adjust the flows so that directly measured and estimated exports will sum
to the known tonnage of total exports shipped to all destinations. Record these numbers in Column (11), Final
Adjusted Exports, and fill in column with the directly measured values from Column (8).
Table D2. Calculation of Minnesota Exports from the state to state commodity shipments found in the
Commodity Flow Survey as Additional Data in Table 12.
All All Instate
SCTG Destinations Destinations Value Instate
Code Value($mil) Tons(OOO) $/ton (mil $) Tons (000)
Col. 1 Column 3 Column 4 Col. 5 Col. 6 Col. 7
Total
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
35570
-
S
129
609
29
223
365
440
S
32
53
S
S
4943
393
227
532
3918
1996
S
1512
2582
370
900
69
123
483
S
937
4158
860
233760
-
S
467
259
14
S
351
19
S
793
5667
S
S
187835
S
964
3335
5152
S
S
946
1316
5627
3869
108
87
S
S
5007
6306
851
0
0
356
276
2351
2071
843
1040
23158
94
40
9
29
689
26
272
235
160
760
32716
216
1598
1962
66
233
639
1414
2499
9097
187
659
1011
8336
-
S
87
50
20
S
365
111
S
4
51
S
S
1107
S
224
78
425
S
S
518
485
132
216
S
58
S
S
263
449
525
66249
-
S
438
21
11
S
351
7
S
347
5484
S
S
44488
S
954
163
897
S
S
290
387
S
1045
S
S
S
S
3658
S
465
Directly Estimate Estimate Final
Measured Instate State Adjusted
Exports Tons(OOO) Exports Exports
Col.8 Col.9 Col. 10 Col. 11
167511
0
0
S
29
238
3
S
0
12
S
446
183
S
S
143347
S
10
3172
4255
S
S
656
929
S
2824
S
S
S
S
1349
S
386
S
S
S
S
S
S
S
S
2007
S
41
S
S
681
167511
0
0
0
29
238
3
0
0
12
0
446
183
0
0
143347
0
10
3172
4255
0
0
656
929
3620 3406
2824
0
46 43
0
0
1349
5625 5294
386
129
-------
Environmental Accounting Using Emergy: Minnesota
Table D2 Continued
All All
SCTG Destinations Destinations
Code Value($ mil) Tons(OOO)
34
35
36
37
38
39
40
41
43
~
2109
1326
2900
320
234
159
692
S
794
187
120
519
S
2
45
134
S
425
99 38
Instate
Value Instate
$/ton (mil $) Tons (000)
11278
11050
5588
10622
117000
3533
5164
148
1868
2605
483
242
212
S
S
57
140
S
605
S
48
S
S
S
-
12
S
S
314
S
Class Totals
Difference (Total - Class Total from Column 7 in this
Fraction (Difference/Class Total (Column 7/Column
table)
Table.
9 this
Directly Estimate Estimate Final
Measured Instate State Adjusted
Exports Tons(OOO) Exports Exports
139
S
S
S
S
33
S
S
111
S
158122
9389
0.941
22
38
S
S
27
S
S
139
98 92
481 453
0
0
33
107 101
0
111
0
9977 167511
Import Calculations
Table 12 from the CFS web site, "Additional State
Data", used in the export calculation, has information on
the exports by commodity class going from all the other
states to the state of destination (Minnesota). Data from
the other 49 states that might be exporting to Minnesota
were combined to determine imports. Inbound
shipments by state of origin to the state of destination
are summarized in Table 8 of the CFS, but commodity
classes are not shown. For states without a U.S.
Customs port, state to state commodity shipments will
capture almost everything entering the state for use or
transshipment. When one or more U.S. customs ports
are located in a state the accounting becomes more
difficult. Should the foreign imports be added, if they
are destined for other places and are thus immediately
exported to another state? If the majority of imports
entering through a major port belong to some other
place the international flows could greatly exceed the
interstate flows and lead to large errors in our estimates.
We assume that most international shipments pass
through Minnesota and do not pertain to the state's
economy, thus our estimate of Minnesota imports will
be conservative, because some unknown fraction of the
international flows will be used in Minnesota directly.
The inbound tonnage shipped in each commodity
category was used to calculate the emergy imported in
goods. The five steps used to estimate imported emergy
to a state are as follows: (1) a quick tally of the total
tonnage coming into the state from other states was
obtained by consulting Table 8 in the CFS report. The
states that had a number entered in the percent of total
inbound shipments column were identified. The total
percentage of imports directly measured was determined
by summing the percentages. The total percent of
tonnage from the states used to estimate imports should
be at least 95% of the tonnage of total inbound
shipments. (2) Once the subset of states exporting to the
study state was identified, missing values for the
tonnage for specific commodities coming from each
state were estimated. (3) If a dollar value of the inbound
commodity shipments was known and tonnage was not
listed, the tonnage was estimated based on the cost per
ton as described above and shown in Table D2. A large
fraction of total inbound shipments from some states
had missing values for both dollar value and tonnage (an
S or D entered into the field). In this case, the missing
data would have resulted in large errors in the estimate
of total imports and thus the development of a method to
handle this situation was warranted. The tonnage fields
for inbound shipments from a state of origin to
Minnesota containing and S or a D were handled by
assuming that a state's exports to any other state would
on average follow its overall export profile, i.e., the
fraction of total shipments accounted for by each
commodity. Missing tonnage data was distributed
130
-------
Appendix D
among commodity classes by adjusting the overall
export profile. The missing tonnage is equal to total
shipments to Minnesota from the state minus
commodities with numeric entries for tonnage. This
tonnage was distributed among the commodity classes
with inbound shipments by adjusting using the state's
overall export profile so that the unknown inbound
shipments made up 100% of the missing inbound
tonnage. (4) The inbound tonnage in each commodity
class for a state was transferred as a single column to a
second worksheet with data from all of the identified
import states. (5) Then each commodity class was
summed across the rows for all states to create the
column of data with imported tonnages in each
commodity class for the emergy table.
1. The following steps describe the estimation of the
unknown tonnage (S and D) as illustrated for
Alabama's shipments to West Virginia (our original
example) shown in Table D3. For all of the states
importing to the study state, copy the total tonnage in
each commodity class exported to all destinations
and the tonnage exported to the state you are
evaluating (columns 2 and 3 in Table D3), onto a
spreadsheet..
2. Calculate the price per ton for all inbound shipments
by commodity class from any state exporting to the
study state according to the instructions given above
for exports.
3. Replace all dashes with a zero. Although Table D3
only presents one state, the same procedure will be
used for all states sending a significant quantity of
imports to the study state.
4. Next, missing tonnage values are estimated for any
commodity class that reported a dollar value of
exports to the state but no tonnage. In some cases
calculating the price per ton for the state of origin is
not possible, but there is still a dollar value for
exports. Prices per ton can be quite variable but find
an adjacent state (or use a better estimation method)
and substitute this price in the spreadsheet making a
note on its origin. Fill in all tonnage movements
possible using this method. Combine the tonnages
estimated on the basis of average price with the
tonnages that were directly measured. Sum this
column and subtract from the total tonnage exported
to the study state to get the tonnage that will be
distributed using the export profile (see the number
in italics at the top of column 4 in Table D3). For
example, the total export from Alabama to West
Virginia is 318 thousand tons but the sum of all
commodities determined directly and estimated
based on dollar value only adds up to 27 thousand
tons, the difference is then 291 thousand tons.
5. Create a fourth column for the export profile, which
will be used to distribute the missing tonnage across
the remaining commodities that had either an S or D
in both the dollar value and tonnage fields. The
export profile is the fraction of the total tonnage
accounted for by each commodity as determined
from the shipments to all destinations. Calculate the
profile by dividing the tonnage for each commodity
exported by the total tonnage exported for that state.
Only those commodities that have an S or D in both
dollar value and tonnage fields are recorded in
column 4. Sum the fractions to determine the fraction
of total tons accounted for by the commodities with
missing data.
6. The next step is to adjust these fractions to represent
the expected fractions of the missing tonnage
imported to the state in each commodity class with
missing data. Create a fifth column, the adjusted
fraction of missing tonnage imported in each class,
where each fraction of the tons in the export profile
(individual values in column 4) will be divided by
the fraction of the total tons that is missing (the sum
of all fractions in column four). The sum of all
values in column 5 should equal one, or 100%.
7. In the last column (column 6), copy over the reported
and estimated data for tonnage for any commodity
where it is available from column 3. For all of the
missing commodities (those with and S or D in both
the $ value and tonnage fields), multiply the total
missing tonnage (at the top of Column 4) by the
corresponding percentage (in Column 5) for each
commodity class known to have a flow but for which
tonnage is unknown, and transfer this number to the
appropriate field in column 6. For example, if data is
missing for textiles, multiply 291 thousand tons by
the fraction of textiles or 0.0172, to get 5 thousand
tons textiles imported. Sum this column to make
sure it adds up to the total tonnage.
8. Transfer this tonnage data for each commodity to an
import table creating a column for each state.
9. Sum across the states (rows) for each commodity to
find the total tonnage imported in each commodity
class and transfer this to the import section of the
emergy evaluation.
131
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Environmental Accounting Using Emergy: Minnesota
Use Table Dl or better conversion system to convert from NAICS to SCTG code. Create a column for this data and
include it in the summation of imports described in step 9 above.
Table D3: Our original example of estimating missing import data. Alabama to West Virginia.
Description
All commodities
Live animals and live fish
Cereal grains
Other agricultural products
Animal feed and products of animal
origin
Meat, fish, seafood, and their
preparations
Milled grain and bakery products
Other prepared foodstuffs and fats and
oils
Alcoholic beverages
Tobacco products
Monumental or building stone
Natural sands
Gravel and crushed stone
Nonmetallic minerals
Metallic ores and concentrates
Coal
Gasoline and aviation turbine fuel
Fuel oils
Coal and petroleum products,
Basic chemicals
Pharmaceutical products
Fertilizers
Chemical products and preparations
Plastics and rubber
Logs and other wood in the rough
Wood products
Pulp, newsprint, paper, and
paperboard
Paper or paperboard articles
Printed products
Textiles, leather, and articles of
textiles or leather
Nonmetallic mineral products
Base metal in primary or semi finished
forms and in finished basic shapes
Articles of base metal
Machinery
Electronic and other electrical
equipment and components
Total Tons
from
Alabama
(thousands)
256234
125
S
1682
7194
1836
386
4408
482
51
S
S
36211
2905
S
30993
12659
3605
4671
7460
33
2382
1271
1585
40817
12443
8949
977
324
2120
16613
11212
4208
753
688
Tons to
WV
(thousands)
318
-
-
-
S
S
S
S
-
S
-
-
-
S
-
-
-
-
S
S
S
S
S
S
S
S
S
-
S
S
S
17
S
1
S
Fraction
of total
tons for
missing
data
297
0.028
0.007
0.002
0.017
0.000
0.011
0.018
0.029
0.000
0.009
0.005
0.006
0.159
0.049
0.035
0.001
0.008
0.065
0.016
0.003
Fraction
of
missing
tonnage
toWV
0.059
0.015
0.003
0.036
0.000
0.000
0.000
0.000
0.000
0.024
0.000
0.000
0.000
0.000
0.038
0.061
0.000
0.020
0.010
0.013
0.334
0.102
0.073
0.000
0.003
0.017
0.136
0.034
0.000
0.006
Total Tons
toWV
(thousands)
0.0
0.0
0.0
17.2
4.4
0.9
10.5
0.0
0.1
0.0
0.0
0.0
6.9
0.0
0.0
0.0
0.0
11.1
17.8
0.1
5.7
3.0
3.8
97.3
29.7
21.3
0.0
0.8
5.1
39.6
17.0
10.0
1.0
1.6
132
-------
Appendix D
Motorized and other vehicles
(including parts)
Transportation equipment
Precision instruments and apparatus
Furniture, mattresses and mattress
supports, lamps, lighting fittings,
and...
Miscellaneous manufactured products
Waste and scrap
Mixed freight
Commodity unknown
957
251
10
501
2965
2130
2000
S
S
S
-
S
9
-
-
-
0.004 0.008
0.001 0.002
0.000
0.002 0.004
2.3
0.6
0.0
1.2
9.0
0.0
0.0
subtotals to check
Custom's Imports
Our present view on customs data is that the portion
of these imports that are used within the state is captured
by the CFS data. Including these flows that really
pertain to the whole nation in the analysis of an
individual state alters the indices so they are not longer
comparable to states without customs facilities.
Nevertheless, we repeat our original instructions for
obtaining customs' data in case it is of interest in a
particular analysis. If the state has a Customs' port,
locate the appropriate data on the USITC data web site
(37). The Customs' site requires a password, but
registration is free. To get the correct data report, a
series of dialogue boxes must be completed. The
choices that should be made are as follows:
27
0.476
1.000
318
Dialogue 1 - U.S. General Imports; NAICS code;
current US Trade
Dialogue 2 - Customs value; 1997; All import
commodities; All countries; All country sub-codes;
create new district list
Enter the name, select the districts, then highlight the
name when you return to original page;
In 1,000,000; annual; NAICS 3 digit; aggregate all
countries together; aggregate import programs;
display districts separately
Dialogue 3 - Arrange in this order: District; NAICS 3
Dialogue 4 - District; General customs value; Show
all; Sort 1997; 5000 records; other display options are
optional
133
-------
Environmental Accounting Using Emergy: Minnesota
Appendix E
Minnesota Emergy Accounts for 2000
134
-------
Appendix E
Table El. Annual Renewable Resources and Production in 2000.
Note*
Item
Data
J, g, $, ind/yr
Units
Emergy/
Unit
sej/unit
Emergy
E+20 sej
2000
Emdollars
E+6 Em$
Renewable Resources within Minnesota
1
1
2
3
4
5
6
6
7
7
8
9
9
10
10
11
11
12
13
14
15
16
17
18
19
20
21
Sun, Incident
Sun, Absorbed
Wind Kinetic Energy
Earth Cycle Energy
Rain, Chemical Potential Energy Received
Evapotranspiration, Chemical Potential Absorbed
Rain, Geo-Potential On Land
Snow, Geo-Potential On Land
Rain, Geo-Potential Of Runoff
Snow, Geo-Potential Of Runoff
Wave Energy (Lake Superior)
Rivers, Chemical Potential Energy Received
Rivers, Chemical Potential Energy Absorbed
Rivers, Geo-Potential Energy Received
Rivers, Geo-Potential Energy Absorbed
NH4-N In Dry /Wet Deposition
NO3-N In Dry /Wet Deposition
Total N Deposition
S In Dry /Wet Deposition
Cl In Dry/Wet Deposition
Minnesota
Agricultural Products
Livestock
Fish Production
Hydroelectricity and Other Renewable
Net Timber Growth
Timber Harvest
Groundwater Chemical Potential
Solid Waste Recycled or Recovered
1.07E+21
8.84E+20
1.26E+19
2.80E+17
7.07E+17
3.14E+17
4.58E+17
7.22E+16
2.55E+16
4.67E+16
1.55E+16
9.15E+15
6.44E+12
5.09E+15
1.51E+15
1.55E+11
4.44E+10
2.00E+11
5.26E+10
8.81E+09
7.00E+17
5.97E+16
1.32E+11
1.07E+16
1.28E+17
6.40E+16
4.61E+15
3.28E+12
J
J
J
J
J
J
J
J
J
J
J
J
J
J
J
g
g
g
g
g
J
J
J
J
J
J
J
g
1
1.21
1,467
33,720
18,100
28,100
10,100
101,100
27,200
101,100
30,000
50,100
50,100
27,200
27,200
1.4E+09
6.8E+09
Variable
1.58E+11
1.31E+10
Variable
Variable
1,961,800
120,300
20,600
68,700
159,100
6.28E+09
10.74
10.74
185.47
94.35
127.95
88.30
46.23
73.04
6.93
47.19
4.66
4.58
0.003
1.39
0.41
2.15
3.04
5.19
83.18
1.15
2,632.5
533.8
0.003
12.9
26.4
43.9
7.3
206.2
456.9
456.9
7892.3
4014.7
5444.6
3757.5
1967.1
3108.1
294.9
2008.0
198.1
195.0
0.1
59.0
17.4
91.6
129.2
220.8
3539.9
49.1
112023.1
22714.9
0.1
548.2
1124.5
1869.5
311.9
8772.8
: The notes for Table 4 can be found in Appendix C at C. 1.
135
-------
Environmental Accounting Using Emergy: Minnesota
Table E2. Annual Production and Use of Nonrenewable Resources in 2000.
Note*
Fuels and
22
23
24
25
26
27
28
29
30
31
32
33
Item
renewables used in a nonrenewable
Coal Used In The State
Natural Gas Used In The State
Petroleum Used In The State
Electricity Production
Electricity Used In The State
Nuclear Electricity
Iron Ore Mined
Sand And Gravel
Limestone
Dolomite
Peat
Soil Erosion
Data
J, g, $, md/yr
manner
5.53E+17
3.98E+17
7.20E+17
1.74E+17
2.15E+17
4.67E+16
4.67E+13
3.95E+13
6.40E+12
3.37E+12
7.50E+10
9.79E+16
Units
J
J
J
J
J
J
g
g
g
g
g
J
Emergy/Unit
sej/unit
37,800
43,500
64,800
170,400
170,400
170,400
3.51E+9
1.31E+9
9.81E+8
1.08E+10
3.53E+8
72,600
Emergy
E+20 sej
209.1
173.2
466.8
297.0
366.4
79.5
1639.0
517.5
63.8
363.3
0.3
71.1
2000
Emdollars
E+6 Em$
8899.7
7370.9
19865.4
12636.6
15592.9
3383.1
69745.5
22019.1
2671.4
15460.6
11.3
3023.6
The notes for Table E2 can be found in Appendix C at C2.
Table E3. Annual Imports to the Minnesota Economy in 2000.
Note*
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
Item
Tourism (Money Imported)
Electricity
Uranium
Coal
Petroleum
Natural Gas
Minerals
Goods (Materials)
Goods (Services)
Fuels (Services)
Minerals including Uranium (Services)
Electricity (Services)
Services
Immigration
Federal Government Outlays
(If spent in US)
Data
J, g, $, md/yr
9.00E+09
3.01E+16
2.94E+09
5.53E+17
7.20E+17
3.98E+17
1.06E+13
3.92E+13
6.60E+10
5.51E+09
4.78E+08
6.22E+08
4.22E+09
8.67E+03
2.24E+10
Units
$
J
g
J
J
J
g
g
$
$
$
$
$
Ind.
$
Emergy/Unit
sej/unit
2.35E+12
1.70E+05
4.66E+11
3.78E+04
6.48E+04
4.35E+04
variable
variable
2.35E+12
2.35E+12
2.35E+12
2.35E+12
2.56E+12
variable
2.35E+12
Emergy
E+20 sej
211.5
51.3
13.7
209.1
466.8
173.2
106.0
2747.9
1550.5
129.5
11.2
14.6
108.1
4.2
526.2
2000 Emdollars
E+6 Em$
9000.0
2182.0
583.1
8899.7
19865.4
7370.9
4512.6
116930.0
65977.0
5509.2
477.9
621.7
4598.8
180.5
22391.9
-------
Appendix E
Table E4. Annual Exports from the Minnesota Economy in 2000.
Note*
Item
Data
J, g, $, ind/yr Units
Emergy/Unit Emergy 2000 Emdollars
sej/unit E+20 sej E+6 Em$
49
50
51
52
53
54
Goods w/o Iron Ore and Fuels (Materials) 7.37E+13
Iron Ore as Taconite 3 . 5 7E+ 1 3
Goods (Services) 9.46E+10
Services 1.36E+09
Federal Government Taxes (Spent in the
US) 2.85E+10
Tourists (Experiences Taken Home) 9.00E+09
* The notes for Table E4 can be found in Appendix C at
Table E5. Assets of Minnesota in 2000.
Note*
55
56
57
58
59
60
61
62
63
64
65
66
67
Item
Forest Biomass Storage
Water (Lakes)
Water (Lake Superior)
Soils
Iron
Sand & Gravel
Limestone
Dolomite
Copper
Nickel
Peat
Platinum
People
Preschool
School
College Grad
Post-College
Public Status
Legacy
Data
J, g, $, ind/yr
6.26E+18
6.76E+17
3.30E+17
9.42E+19
1.40E+16
3.19E+16
2.82E+15
1.32E+14
4.50E+15
4.50E+15
7.57E+19
2.90E+13
329605
2402204
1882631
255844
49195
765
329605
C4.
g mixed 3855 164037.5
g 3.61E+09 1290.4 54909.2
$ 2.35E+12 2223.0 94597.0
$ 2.35E+12 31.9 1356.7
$ 2.35E+12 668.8 28460.0
$ 3.97E+12 357.3 15202.9
Emergy/Unit Emergy
Units
J
J
J
J
g
g
g
g
g
g
J
g
Ind.
Ind.
Ind.
Ind.
Ind.
Ind.
Ind.
sej/unit
28,200
18,100
2.40E+05
72,600
3.51E+09
1.31E+09
9.81E+08
1.08E+10
1.14E+11
2.55E+10
1.86E+04
1.13E+11
Various
3.34E+16
9.22E+16
2.75E+17
1.28E+18
3.85E+18
7.70E+18
E+20 sej
1767
122
792
68375
490324
417826
27661
14231
5115002
1147664
14100
32728
12738
110
2215
5171
3288
1896
59
2000 Emdollars
E+6 Em$
75,202
5,206
33,692
2,909,574
20,864,869
16,321,327
1,177,080
605,577
217,659,670
48,836,772
599,999
1,392,699
542,061
4678
94253
220029
139895
80699
2507
* Evaluation notes for Table E5 are given in Appendix C at C5.
137
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Table E6. Summary of Flows for Minnesota in 2000.
Letter in
Note Fig. 2 Item
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
RA
Ri
N
N/
No
N!
N2
F
Fi
F2
G
I
Ii
I2
I3
I4
I5
P2I
P2Ii
P2I2
P2I3
PiI4
Pils
B
E
Ei
E2
E3
E4
P2E
P2Ei
P2E2
P2E3
X
P2
Pi
Renewable Sources Used
Renewable Electricity
Nonrenewable Source Flows
Extracted Fuels and Minerals
Dispersed Rural Source
Concentrated Use (from state)
Exported (without full use)
Imported Fuels and Minerals)
Fuels, Minerals Used (F+F2)
In State Minerals Used (N/-N2)
Imported Goods (Materials)
Dollars Paid For All Imports
Dollars Paid For Service In Fuels
Dollars Paid For Service In Goods
Dollars Paid For Services
Dollars Spent By Tourists
Federal Transfer Payments
Imported Services Total
Imported Services In Fuels
Imported Services In Goods
Imported Services
Emergy Purchased By Tourists
Net Emergy Purchased By Fed. $
Exported Products w/o Taconite
Dollars Paid For All Exports
Dollars Paid For Goods
Dollars Paid For Mineral Exports
Dollars Paid For Services
Federal Taxes Paid
Total Exported Services
Exported Services In Goods
Exported Services In Iron
Exported Services
Gross State Product
Emergy/ $ Ratio U.S. 2000 sej/$
Emergy/ $ Ratio MN 2000 sej/$
2000
Emergy Dollars
E+20 sej E+9 $/y
191
13
2654
2583
71
1385
1290
1020
2313
1292
2748
82.3
6.9
70.8
4.6
9.0
22.4
1933
161.5
1664
108
357
-241
3855
104.2
101.5
1.3
1.5
28.5
2449
2385
30.1
34.2
185.1
2.35E+12
3.97E+12
2000
Emdollars
E+9 Em$/y
8.1
0.5
112.9
109.9
3.0
58.9
54.9
43.4
98.4
55.0
116.9
82.3
6.9
70.8
4.6
15.3
-10.3
164.0
104.2
101.5
1.3
1.5
-------
Table E7. Minnesota Emergy Indicators and Indices for 2000.
Appendix E
Item Name of Index
Expression
Quantity Units
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
Renewable Use
In State Non-Renewable Use
Imported Emergy
Total Emergy Inflows
Total Emergy Used
Total Exported Emergy
Emergy Used From Home Sources
Imports-Exports
Ratio Of Export To Imports
Fraction Used, Locally Renewable
Fraction Of Use Purchased Outside
Fraction Used, Imported Service
Fraction Of Use That Is Free
Ratio Of Purchased To Free
Environmental Loading Ratio
Investment Ratio
Use Per Unit Area
Use Per Person
Renewable Carrying Capacity
Developed Carrying Capacity
MN State Econ. Product
Ratio MN Emergy Use To GSP
Ratio U.S. Emergy Use To GNP
Ratio Electricity Use/Emergy Use
Ratio Elec. Prod./Emergy Use
Emergy Fuel Use Per Person
Population
Area
Renewable Empower Density
RA
NO + N!
F + G + P2I
R + F + G + P2I
u = (RA+NO+FJ+G+ P2i)
B+ P2E +N2
(N0+F2+ R)/U
(F+G+ P2I)-(B+P2 E+N2)
(B+P!E+N2)/(F+G+P2I)
R/U
(F + G + P2I)/U
P2I/U
(R+N0)/U
(F1+G+P2I)/(R+N0)
(F!+No+G+P2I)/R
(F+G+P2I)/(R+N0+F2)
U/Area
U/Population
(R/U)*(Pop.)
8* (R/U)* (Population)
GSP
U/GSP
U/GNP
El/U
Elp/U
F2/Population
1.91E+22
1.46E+23
5.70E+23
5.89E+23
7.35E+23
7.59E+23
0.21
-1.89E+23
1.33
0.026
0.778
0.271
0.036
26.73
37.08
3.67
3.26E+12
1.49E+17
127,574
1,020,589
1.9E+11
3.97E+12
2.35E+12
0.047
0.034
1.73E+16
4,919,479
2.25E+11
8.46E+10
sej y'1
sej y"1
sej y-1
sej y-1
sej y"1
sej y-1
sej y"1
sej/m2
sej/ind.
people
people
$/yr
sej/$
sej/$
J/sej
J/sej
sej/ind
people
m2
sej/m"2
139
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