SEPA
United States
Environmental Protection
Agency
Industrial Environmental Research
Laboratory
Research Triangle Park NC 27711
EPA-600 7-79-091
March 1979
Nuclear Power Plant
Waste Heat Horticulture
Interagency
Energy/Environment
R&D Program Report
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RESEARCH REPORTING SERIES
Research reports of the Office of Research and Development, U.S. Environmental
Protection Agency, have been grouped into nine series. These nine broad cate-
gories were established to facilitate further development and application of en-
vironmental technology. Elimination of traditional grouping was consciously
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The nine series are:
1. Environmental Health Effects Research
2. Environmental Protection Technology
3. Ecological Research
4. Environmental Monitoring
5. Socioeconomic Environmental Studies
6. Scientific and Technical Assessment Reports (STAR)
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This report has been assigned to the INTERAGENCY ENERGY-ENVIRONMENT
RESEARCH AND DEVELOPMENT series. Reports in this series result from the
effort funded under the 17-agency Federal Energy/Environment Research and
Development Program. These studies relate to EPA's mission to protect the public
health and welfare from adverse effects of pollutants associated with energy sys-
tems. The goal of the Program is to assure the rapid development of domestic
energy supplies in an environmentally-compatible manner by providing the nec-
essary environmental data and control technology. Investigations include analy-
ses of the transport of energy-related pollutants and their health and ecological
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This report has been reviewed by the participating Federal Agencies, and approved
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This document is available to the public through the National Technical Informa-
tion Service, Springfield, Virginia 22161.
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EPA-600/7-79-091
March 1979
Nuclear Power Plant
Waste Heat Horticulture
Editors
i
Thomas Sproston (Plant Biologist Inc.),
E.P. Gaines, and D.J. Marx
Vermont Yankee Nuclear Power Corporation
77 Grove Street
Rutland, Vermont 05701
Grant No. R804715
Program Element No. EHE624
EPA Project Officer: Theodore G. Brna
Industrial Environmental Research Laboratory
Office of Energy, Minerals, and Industry
Research Triangle Park, NC 27711
Prepared for
U.S. ENVIRONMENTAL PROTECTION AGENCY
Office of Research and Development
Washington, DC 20460
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ACKNOWLEDGMENT S
Donald R. Price, Cornell University, Ithaca, NY 14853
William J. Jewell, Cornell University, Ithaca, NY 14853
Thomas D. Hayes, Cornell University, Ithaca, NY 14853
H. Reed Witherby, Ropes & Gray, Attorneys, Boston, MA 02110
James D. Batson, Dartmouth College, Hanover, NH 03755
Linda S. Halstead, University of Vermont, Burlington, VT 05401
Joe Kent, Kramer, Chin & Mayo, Inc., Seattle, WA 98101
11
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ABSTRACT
The possibility of using Vermont Yankee condenser
effluent waste heat for commercial food growth enhancement
was examined. It was concluded that, for the Vermont Yankee
Nuclear Station, commercial success, both for horticulture
and aquaculture projects, could not be assured without
additional research in both areas. This is due primarily to
two problems. First, the low heat quality (temperature) of
the condenser discharge, being nominally 22°C + 1°C (72° +
2°F)* and second, to the capital-intensive support systems.
The capital required for support systems includes costs of
pumps, piping, controls and site work necessary to conduct
heated water to growing facilities and the costs of large,
efficient heat exchangers that may be necessary to avoid
regulatory difficulties caused by the 1958 Delaney Amendment
to the U.S. Food, Drug and Cosmetic Act.
Recommendations for further work include construction
of a permanent aquaculture research laboratory and a test
greenhouse complex designed by Cornell University staff,
wherein several different heating configurations would be
installed and tested. One greenhouse would be heated with
biogas (60% methane) from an adjacent anaerobic digester
thermally augmented during the winter months by Vermont
Yankee condenser effluent heat.
The aquaculture laboratory would initially be used to
raise fingerling Atlantic salmon (Salmo salar) to smolt size
within seven months using water warmed to approximately 15°C
(60°F). The growth rate by this technique is increased two
to threefold over conventional hatcheries or natural conditions.
*Whenever possible, throughout this report, data have been
presented in both metric and English units. There are
sections of the report, however, where metric units have not
been used. This is because some data were obtained from
engineering consultants who customarily use English units
for professional design services. When adding metric units
to the text or drawings would overly complicate reading and
interpretation, they have been omitted and the reader is
referred to the following conversion table:
Centimeter (cm) = Inches (in) x 0.3937
Meters (m) = Feet (ft) x 0.3048
Square meters (m2,) = Square feet (SF or ft2) x 0.0929
Square meters (m ) = Acres (AC) x 4047
Cubic meters (m3) = Gallons X 0.0038
Cubic meters (m3) = Cubic feet (ft3) x 0.0283
Degrees Celsius (°C) = (°F - 32) x 0.56
Kilograms (kg) = Pounds (Ibs) x 0.4536
lit
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PREFACE
This report is a summary of results of work sponsored
by the U.S. Environmental Protection Agency (EPA) under
Grant No. R804715-01-1 having the principal objective of
investigating the practical possibilities of using Vermont
Yankee power plant waste heat for horticultural enhancement.
The report necessarily includes summary results of a
corollary effort sponsored by the U.S. Energy Research and
Development Agency (ERDA)* under Contract No. EY-76-C-02-2869.M001
This contract had similar objectives with regard to commercial
aquaculture using Vermont Yankee waste heat. Because the
two projects are interdependant by virtue of mutual support
facilities (piping, pumps, service buildings, etc.), the
two projects were combined into an integrated system concept.
Additional aquaculture details are described in ERDA Report
No. C002869-1.
The Vermont Yankee Nuclear Power Corporation believes
the recommendations made herein, representing completion of
the conceptual design phase of the horticulture enhancement
investigation, can be satisfactorily implemented without
interfering with plant electrical generating capabilities.
The Corporation therefore plans to make available company-
owned sites suitable for the construction of the horti-
culture test complex described. Furthermore, the Corporation
plans to make available main condenser discharge water in
volumes up to plant capacity at no cost to waste heat
projects, provided such projects do not interfere with
electrical generating capabilities. Finally, the Corporation
plans to make available suitable personnel to function as
project coordinators between plant operations and waste heat
utilization programs and experiments. The Corporation
looks forward to making substantial contributions to energy
conservation efforts.
*Subsequent to the commencement of thxs project ERDA was reor-
ganized and incorporated into the U.S. Department of Energy.
IV
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TABLE OF CONTENTS
ACKNOWLEDGMENTS ii
PREFACE iv
ABSTRACT iii
LIST OF FIGURES vii
LIST OF TABLES viii
CHAPTER 1 - SUMMARY 1
1.1 INTRODUCTION 1
1.2 SYSTEM CONCEPT 5
1. 3 RESULTS 9
1.4 CONCLUSIONS 15
1.5 TEST PROGRAM IMPLEMENTATION 15
CHAPTER 2 - HORTICULTURE PROGRAM 19
2.1 GREENHOUSES 19
2.2 BIOGAS GENERATOR 20
2.3 HORTICULTURE LAYOUT 21
CHAPTER 3 - SUPPORT SYSTEMS 23
3.1 PUMP STATION 23
3.2 HEAT EXCHANGER BUILDING 25
3.3 WASTEWATER TREATMENT FACILITIES 26
3.4 ON SITE AND OFF SITE WORK 27
3.5 PLANT DISCHARGE WATER 28
CHAPTER 4 - COST ESTIMATES 29
4.1 CAPITAL COSTS INCLUDING CONSTRUCTION 29
4.2 OPERATION AND MAINTENANCE COSTS 35
v
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TABLE OF CONTENTS
APPENDICES Page
APPENDIX A - FEDERAL LAWS AFFECTING VERMONT YANKEE
WASTE HEAT PROJECT 37
APPENDIX B - WASTE HEAT BOOSTING FOR ANAEROBIC
FERMENTER EFFICIENCY IMPROVEMENT 59
APPENDIX C - WASTE HEAT UTILIZATION DEMONSTRATION
GREENHOUSE DESIGN CONCEPT 83
APPENDIX D - ORNAMENTAL HORTICULTURE USING BIOGAS-
BOOSTED GREENHOUSES 121
Vl
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LIST OF FIGURES
Figure Page
1.1 Heat Dissipation System, Vermont
Yankee Nuclear Power Station ....... 2
1.2 Average Vermont Temperature ..... ... 3
1.3 Ambient Connecticut River Temperatures . . 4
1.4 Sketch of Vermont Yankee Waste Heat
Utilization Concept ............ 5
1.5 Fluid Flow Balance Diagram ........ 6
1.6 Plan View of Aqualab ........... 7
1.7 Cornell Greenhouse ............ 8
1.8 Greenhouse Heating Methods ........ 8
1.9 Plan View of the Greenhouse Complex. ... 12
1.10 Aqualab Construction Schedule ....... 16
1.11 Horticulture Test Complex Construction
Schedule ................. 17
2.1 Power Plant Site Horticulture Program. . . 21
3.1 Power Plant Site Support Systems ..... 23
3.2 Support Systems: Pump Station and Heat
Exchanger,
24
VII
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LIST OF TABLES
Table Page
1-1 AQUALAB CAPITAL COST SUMMARY 10
1-2 OPERATION AND MAINTENANCE COSTS .... 11
1-3 ESTIMATED PRODUCTION INCOME 13
1-4 SUMMARY OF COMMERCIAL HORTICULTURE. . . 14
4-1 CAPITAL COSTS - CONSTRUCTION COST
SUMMARY 31
4-2 CAPITAL COST ESTIMATE (UNIT COSTS)... 32
4-3 OPERATION and MAINTENANCE COSTS .... 36
viii
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CHAPTER 1
SUMMARY
1.1 INTRODUCTION
Early in the evolution of current concerns over the
diminishing availability of primary energy sources, the role
of conservation was recognized as a major component in any
practical, long-term energy program. Besides population
control, discovery and recovery of additional sources of
fossil fuels and the development of new "alternative" energy
conversion schemes, there is the potential for improving
efficiencies of the overall thermal balance of heat machines
in use today so that more work is obtained from the energy
consumed.
In the case of large electrical generating stations,
whether nuclear or fossil, more than 50 percent of the total
energy input is lost in the conversion of heat to electricity.
Ideas of how to recover this energy have ranged from the
design of ancillary heat engines operating in temperature
regimes between exhaust gases or condenser effluent and
adjacent cooling ponds and rivers to using the reject heat
for melting snow and ice in nearby communities. Most of
these ideas, for the present at least, can be eliminated for
obvious practical reasons. Heat engines might be possible
but, except for so-called combined cycle systems operated in
conjunction with machines having relatively high exhaust gas
temperatures, their massive dimensions require such large
capital investments as to make the energy they recover
uneconomical.
However, direct utilization of "waste heat" for augmented
food production or growth acceleration seems worthy of
further assessment. The work reported herein is the result
of an initial examination into possible benefits to be
obtained from using large quantities of water heated to a
nominal 22°C + 1°C (72°F + 2°F) by the Vermont Yankee Nuclear
Power Station.
1.1.1 Station Description
The Vermont Yankee Nuclear Power Station is located on the
west bank of the Connecticut River immediately upstream
of the Vernon hydro-electric station, in the town of Vernon,
Vermont. The Vermont Yankee facility occupies about 500,000
square meters (125 acres) bounded by privately owned land to
the north, south, and west and by the Connecticut River to
the east.
The reactor for the Vermont Yankee Station is of the
boiling water design, having a licensed thermal power of
1593 megawatts and designed net electrical rating of 514
megawatts.
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In a boiling water nuclear plant, steam is passed
directly from the reactor to the turbine-generator, then to
the main condensers and back to the reactor vessel. The main
condensers provide a dynamic heat sink for steam condensation.
At Vermont Yankee this heat sink is maintained by continuously
pumping water from the Connecticut River and returning the
heated cooling water to the river or by pumping water cooled
by the cooling towers through the condenser and back to the
towers or by a combination of both these modes. The cooling
towers provide the means of discharging condenser effluent
heat to the atmosphere. Under nominal operating conditions,
the plant condenser delta-T* is 11°C to 17°C (20°F to 30°F).
At full power the plant discharges more than 1300 cubic
meters (366,000 gallons) per minute of heated water, dis-
carding approximately 3 billion BTU's per hour of "waste
heat" (Figure 1.1).
REACTOR
Mi V,FWV»- >TV^1_1VP ^
^^^^^>^5^^-=-, . ^cXy/-' -:
Figure 1.1 Heat Dissipation System, Vermont Yankee
Nuclear Power Station
*The temperature rise of cooling water after passage through
the condenser.
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1.1.2
Seasonal Temperature Profiles
Figure 1.2 illustrates typical ambient air temperatures
in Vermont (11-year average, Burlington International
Airport) showing that Vermont temperatures frequently
average below 10°C (50°F) for more than six months of the
year.
w
&4
S
W
EH
J F M A
Figure 1.2
MJJASONDJ
MONTH
Average Vermont Temperatures
When possible, Vermont Yankee operates its cooling
system to maintain an optimum pressure differential across
the steam turbine. This requires a condenser discharge
temperature of 22°C + 1°C (72°F + 2°F) which is achieved in
winter by mixing ambient river water with warm water re-
circulated from the inner section of the discharge structure.
Thus, under normal operating conditions, large quantities
of water, initially at about 22°C (72°F), are available all
winter for waste heat programs. Even considering temperature
losses of 5°C (10°F) through heat exchangers and conduit
plumbing while in transit to waste heat projects, the poten-
tial benefits from the use of power plant discharge water
are easily envisaged (the "enhanced" growing regions of
Figure 1.3).
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oo o
C °F
25-
80
20--70
Hi
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-5
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•50
-40
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•20
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MONTH
Figure 1.3 Ambient Connecticut River Temperatures
1.1.3
Project Objectives
The objectives of the Vermont Yankee waste heat study
included examination and identification of Vermont Yankee
operating and environmental conditions that could affect the
success of commercial aquaculture and horticulture which are
thermally optimized during winter months using Vermont Yankee
main condenser discharge water. In pursuit of these
objectives, (1) an investigation of the impact of the 1958
Delaney Amendment* to the U.S. Food, Drug and Cosmetic Act
(FDCA) was undertaken; (2) plant and animal species having
good potential for commercial aquaculture and horticulture
were studied and selections made; and (3) a system concept
integrating both horticulture and aquaculture concepts with
the required support facilities was developed and analyzed.
In addition, the possibility of obtaining heat at higher
temperatures than available from the condenser discharge was
explored with corporate engineers and consultants. It was
determined, however, that this could not be done until the
economics of cogeneration were better understood and the
value of trading electricity generation for food products
was established.
*This law prohibits carcinogens in any amounts in food
additives.
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1.2 SYSTEM CONCEPT
The Vermont Yankee waste heat concept has three major
components: aquaculture facilities, horticulture facilities,
and mutual support systems (pumps, heat exchangers, controls,
protective buildings, etc.). Figure 1.4 is a conceptual
diagram of the three components. The dotted box on the left
encloses the major parts of the horticulture component. (Not
shown are the manure preheater, sludge holding tanks,
biogas storage tanks, bi-product fertilizer storage crib,
potable water source, and stand-by heating facilities.) The
right hand dotted box encloses the major parts of the
aquaculture component. (Not shown are the stand-by heating
facilities and potable water supply.) The remaining system
support component also includes roadways, conduit pipes,
and an emergency electrical system as well as the pumps and
heat exchangers. A fluid flow balance diagram for
the integrated system is shown in Figure 1.5.
CONNECTICUT RIVER
DISCHARGE
aquaculture
component
horticulture ANAEROBIC
component
DIGESTER
MANURE
Figure 1. 4 Sketch of Vermont Yankee Waste Heat
Utilization Concept
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HOKTlCULTUeS. PBOGKAM 3UPPOST FACILITIES AQUACULTVKE PROGRAM
Figure 1.5 Fluid Flow Balance Diagram
1.2.1 Aquaculture
The aquaculture component includes a commercial fish
rearing facility consisting of eight enclosed raceways, each
about 24 meters x 4 meters (80 feet x 12 feet). The faci ty
is designed for the annual production of approximately
45,000 kilograms (100,000 pounds) of brook trout (Salvelinus
fontinalis). Fish would be stocked as fingerlings in early
October at 10 centimeters (4 inches) in length to be rear
at a near constant 13°C (55°F) until June of the follow!
year when they would be harvested at a length of approx
23 centimeters (9 inches).
Besides the commercial trout aquaculture facility, the
aquaculture system component includes construction and long-
term operation of a research facility for the study of
problems of intensive, closed-system fish culture. A plan
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view of the aquaculture laboratory is shown in Figure 1.6.
The design includes nine circular rearing tanks, each with
23 square meters (250 square feet) of surface area and eight
smaller tanks providing a research area for 1,000 fish.
Water supplied to these tanks will be in continuous
circular motion and maintained at a temperature of approximately
16°C(60°F). The initial goal of the facility is to produce
approximately 25,000 Atlantic salmon from fingerling size to
smolt between the months of September and April of the
following year. This would be in support of efforts to
restore Atlantic salmon to the Connecticut River and its
tributaries. The long-range goal of the laboratory, however,
would be to generally address problems associated with
intensive closed-system aquaculture.
ooo
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Figure 1.6 Plan View of Aqualab
1.2.2
Horticulture
The horticulture component consists of four greenhouses
designed by Cornell University staff. A cross-section
diagram of the greenhouse is shown in Figure 1.7. Each of
the four greenhouses would be heated in a different way so
that cost comparisons can be made. Figure 1.8 illustrates
the four heating methods planned.
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NORTH-
GREENHOUSE SECTION
Figure 1.7 Cornell Greenhouse
POWER PLANT
HEATED WATER
SUPPLY
-N-
:::/''i-^:V": :-•:.-'•: : NQ '
.""'••• SOLAR'.:.'\';: ;.:'.;•
HE] • WASTE HEAT
•:!';'i':'v:J:.--261x601 :"••'
I
1 »HEAT PUMP
HPJ • WASTE HEAT
: 2$'x60'
SYMBOLS:
HE WATER TO AIR HEAT EXCHANGER
HP WATER TO AIR HEAT PUMP
GH UNIT GAS HEATER
WARM WATER SUPPLY
: DISCHARGE BACK TO RIVER
, METHANE GAS SUPPLY
HEl
IS1
DISCHARGE
TO RIVER,
/
:'-::' • RUTGERS DESIGN i'-^X
PLASTIC EXCHANGERS :
. WASTE HEAT '-:"',:." ;
>'••<••" 26*x60'y:v:"'v ;>o-/
V /
• .... ; • ' : .'.-:-. ..; N0.4_ . .,
• • METHANE FROM '. ' :
JGH") DAIRY WASTES •'•••JGH]
26'x6O' ;T '•'• - .
1 METHANE FROM
J ANAEROBIC GENERATOR
Figure 1.8 Greenhouse Heating Methods
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A unique feature of the horticulture component is
incorporation of an anaerobic digester, converting manure
from an adjacent 200-animal dairy farm to biogas (60% methane)
and concentrated fertilizer. Calculations indicate that
sufficient manure is available from this source to ade-
quately heat one of the experimental greenhouses solely by
burning biogas in conventional gas heaters. The digester
itself would be thermally augmented by the use of Vermont
Yankee condenser effluent to preheat the manure slurry.
Theoretical results indicate that this method could increase
biogas production by 40% or more during winter months.
1.3 RESULTS
1.3.1 Legal Restrictions
An examination of the implications of the 1958 Delaney
Amendment to the Federal Food, Drug and Cosmetic Act has
been made (Appendix A). It concludes that "since the use
of nuclear power plant waste heat for aquaculture and horticulture
is very recent, there is little law which directly establishes
standards applicable to the Vermont Yankee waste heat project.
The requirements affecting the project are chiefly case-by-case
permanent requirements of the Environmental Protection Agency
and the Nuclear Regulatory Commission"—"The precise
application of the Food, Drug and Cosmetic Act (FDCA) depends
largely upon whether heat exchanger* systems are used, and if
they are not, upon the probability that the circulating
water will contain potentially unhealthy substances. If
heat exchangers are used, as is generally contemplated, the
FDCA will not apply unless food accidently becomes contaminated
with poisonous or deleterious substances. If heat exchangers
are not used, the Delaney Clause setting zero tolerance
levels for carcinogens will still not be implicated to the
extent that contamination is not to be expected, despite the
fact that Vermont Yankee is a nuclear station; but a regulation
may be required for certain chemicals or pipe residues
contained in the cooling water. The FDCA also is implicated
if particular food produced at the project becomes contaminated
so as to present a health hazard."
1.3.2 Aquaculture Results
An economic model was developed for the operation of a
commercial trout farm raising approximately 45,000 kilograms
(100,000 pounds) of live weight fish per year. Initial
results indicate that profit cannot be made in today's (1977)
market from this facility due primarily to the high capital
costs involved (principally the costs of heat exchangers and
support facilities). In recognition that the heat exchangers
* Editor's comment:A surface-type exchanger is intended when
"heat exchanger" is used here and throughout this report.
-------
as now contemplated may not be required, and to take advantage
of scaling effects and other economies, the facility was
enlarged by a factor of three, hypothesized to be operated
without heat exchangers, and constructed as economically as
possible. An analysis of the economics of such a facility
with 1977 construction, operation and maintenance costs
suggests a net profit, on the 1977 market, from $10,000 to
$20,000 per year.
Included in this profit is utilization of the facilities
for the production of bait fish during the summer and fall
months and the stocking of fish during the summer and fall
months and the stocking of fingerling trout at 14 centi-
meters (5.5 inches) for growth to 27 centimeters (10.5
inches) during winter months. These adjustments, however,
may not be biologically feasible. Therefore, it was concluded
that the commercial success of a trout fish farm utilizing
Vermont Yankee waste heat cannot be assured on today's (1977)
market. In the future the situation may become more favorable.
However, construction and operation of the aquaculture
research laboratory appears appropriate for the Vermont Yankee
facility. The building and ancillary components will be
constructed for a 40-year life expectancy. Capital and
operation and maintenance costs for this laboratory are shown
in Tables 1-1 and 1-2.
TABLE 1-1
AQUALAB CAPITAL COST SUMMARY (1977 dollars)
Sitework, Paving, and Utilities $ 24,350
Site Mechanical 212,100
Mechanical Building (shell and electrical) 57,500
Mechanical Building (water heating system) 193,700
Rearing Building (shell) 243,000
Rearing Building (mechanical,electrical & tanks) 57,600
Furnishings, Special Equipment and Vehicles 15,700
Subtotal $ 803,950
Mobilization @ 7% 56,280
Contingency @ 15% 129,030
Escalation (Fall 1978) 14% 138,500
Fees and Special Services 112,240
$1,240,000
10
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TABLE 1-2
OPERATION AND MAINTENANCE COSTS
(Aqualab - 8 months of operation)
(1977 dollars)
Water pumping costs based on $0.015 per kwh $18,500
Boiler heating costs based on $0.50 per gallon
Standby 11,000
20-day shutdown 37,500
Building Utilities 1,000
Supplies (including feed) 7,000
Insurance (auto, fire, etc.) 1,000
Maintenance (vehicular, building) 10,000
Labor
1 Manager @ $12,500/year 8,500
2 Assistants @ $10,500/year 7,000
Total $101,500
1.3.3 Horticulture Results
An experimental greenhouse complex has been designed
consisting of four Cornell greenhouses, each heated dif-
ferently (Appendix C). A diagram of the experimental
greenhouse complex is shown in Figure 1.9. A description of
the heating systems for each greenhouse follows:
Greenhouse No. 1; Solar Greenhouse - This structure is
designed to store direct solar heat in gravel beds located
in the greenhouse. Heat is recovered from the gravel
storage system using a commercial water to air heat ex-
changer. A backup heat source is provided by a 9.5-kilowatt
electric resistance heater. No external solar collectors
are utilized. The gravel heat storage units are also used as
produce growing benches. Vermont Yankee condenser effluent
is used as a "booster" heat source in the water to air heat
exchanger. Tomatoes (spring and fall crops) and lettuce are
planned for this greenhouse.
Greenhouse No. 2; Heat Pump - This greenhouse utilizes a
water-to-air heat pump with a constant source of 18°C to
21°C (65°F to 70°F) water supplied by the power plant. The
operating coefficient of performance (COP) for the water to
air heat pump is approximately equal to 3 compared to 1.75 -
2.0 for air to air units now commonly used. In addition to
the heat pump, one commercial water to air heat exchanger
will be used, "boosted" by Vermont Yankee waste heat. The
heat pump will be utilized as the backup heat source in the
event of power plant down-time during the coldest operating
periods. The COP in this mode, however, will be less than
2. English seedless cucumbers are planned for this house.
11
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M£IEOROl.CC;iCH
OPEN DISCHARGE
METHANE STORAGE TANK
DIGESTED SLUOGE UGOCN
METHiNE C4S GtXFDATOKS
MANURE
MANURE HOLDING U*K
^r--
SERVICE BUILDING
WELL HOUSE K0.2
iiiiiini.il 7oo POWER PLANT DISCHARGE
WATER
WASTE OR RETURN WATER
LINES
- —— • POTABLE WATER
METHANE CAS
MANURE
Figure 1.9 Plan View of the Greenhouse Complex
Greenhouse No. 3; Rutgers1 Design - In this design the
floor is constructed of porous concrete with a gravel bed
beneath it. The heat exchangers consist of perforated pipes
draped with polyethylene sheets running the full length of
the house in five separate rows. Water flows from the
perforations in the pipe down between the plastic sheets and
through the porous concrete floor into the gravel bed.
The pipes draped with plastic may be raised at night
for maximum heat exchange and lowered during the day when
less heat is required and more light needed for plant
growth. A commercial water to air heat exchanger will assist
the plastic heat exchangers. The heat exchanger combination
is designed to maintain a minimum of 10 C (50 F) in the
greenhouse on the coldest nights. It is planned to use this
house for potted plants suitable for growth at cool tem-
peratures (snapdragons and chrysanthemums).
Greenhouse No. 4; Methane House - This house is capable of
being totally heated by methane gas produced in a nearby
biogas generator (Appendix B). This generator (also known
as a digester or fermenter) uses the manure from an adjacent
200-cow dairy farm. The manure is converted to a 60% methane
gas mixture by an anaerobic process. The gas is piped to
the greenhouse where it is burned in conventional heaters.
Sufficient gas will be produced to maintain temperatures
above 18 C (65°F) continually during the coldest periods.
Because of the capability of maintaining high temperatures,
plants such as roses can be grown in this greenhouse.
12
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Warm water from the power plant can also be utilized as
a supplemental heat source in the greenhouse and to thermally
augment the anaerobic process. The digester must be maintained
at 32°C-35°C (90°F-95°F) for maximum gas production. The
21°C (70°F) water from the power plant assists in maintaining
the higher temperature in the digester thus increasing gas
production by as much as 40%. Without the assistance of the
warm water from the power plant, nearly one-half of the
methane gas produced would have to be used to keep the
digester at the required 32°C-35°C (90°F-95°F). Using the
warm water to preheat the manure slurry in the digester
during winter months results in only 10%-20% of the gas
produced being required by the digester to maintain optimum
operating temperatures.
Crops to be grown in the various greenhouses have been
selected on the basis of the temperature fluctuations expected.
The plants chosen for each greenhouse are presented in Table
1-3. Since ornamentals, especially roses, in recent years
have provided New England horticulturists the highest net
return on investment, it was decided to design an economic
model for Greenhouse 4 (Appendix D) and examine its operation.
The results are summarized in Table 1-4. Included are the
effects of scaling from the original test complex of four
TABLE 1-3
ESTIMATED PRODUCTION INCOME (1977 dollars)
(Annual)
Greenhouse No. 1
Tomatoes (fall crop)
61b./plant, 390 plants/house @ $.50/lb. $ 1,170.00
Lettuce (winter) 546.00
Tomatoes (spring crop)
14 Ib./plant, 390 plants/house @ $.50/lb. 3,276.00
Total $ 4,992.00/year
Greenhouse No. 2
Cucumbers (English Seedless)
5 crops (3,438 cucumbers/crop)
@ $.40/cucumber 6,876.00
Greenhouse No. 3
Snapdragons and 1 bench of Chrysanthemums 6,380.00
Greenhouse No. 4
2/3 Red Roses (Forever Yours)
1/3 Sweetheart Roses (Bridal Pink) 7,962.00
Total Gross Income $26,210.00
13
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TABLE 1-4
SUMMARY OF COMMERCIAL HORTICULTURE (1977 dollars)
(24 greenhouses - ornamentals, biogas heated)
Capital Investment
First 4 greenhouses $ 538,100
Twenty Additional Greenhouses 164,000
Additional Biogas Generators 180,000
Additional Support Facilities 105,000
Subtotal $ 987,100
Amortized at 9.5% over 30 years (99,600)
0 & M, Greenhouses (115,300)
O & M, Gas Generators (14,200)
Subtotal (229,100)
Gross Receipts, Ornamental Sales 224,600
Gross Receipts, Biogas and Fertilizer Sales 26,500
Subtotal 251,100
Approximate Net Profit $ 22,000
*Estimated Annual Overall Rate of Return: 12%
*Assuming successful demonstration of test unit.
greenhouses and one biogas generator to a total of 24 houses
and four biogas generators. Scaling factors, supplied by
consulting engineers, resulted in an overall costs savings
of 15% for the greenhouses. Scaling factors of 0.80, 0.68,
and 0.65, respectively, were used for each successive biogas
generator. This gave additional costs savings of about 20%
for the four units. The cost of the biogas generators also
includes $90,000 for gas storage facilities. The high cost
of the first four greenhouses includes the cost of one
biogas generator and all support systems (pumps, piping,
controls, service buildings, etc.).
Operation and maintenance (O&M) costs of Table 1-4 are
based upon the data of Chapter 5. Ornamental sales gross
income assumes a return of $64.00 per square meter ($6.00
per square foot) of greenhouse floor space. It is believed
that an efficient operation could achieve this return.
The biogas sales return assumes about 5.0 x 109 BTU of
excess biogas per year available for sales at $2.50 per 10
BTU. The fertilizer sales assumes the processing of manure
from four 200-animal dairy farms. The value of the fer-
tilizer was based upon data cited in the ECOTOPE report
referenced on page D-l, Appendix D.
14
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1.4 CONCLUSIONS
The Vermont Yankee Nuclear Power Corporation has
concluded that the construction of a permanent aquaculture
research facility should be undertaken with the initial
objective of contributing to the expeditious restoration of
Atlantic salmon in the Connecticut River and its tributaries
and with the long-term objective of contributing to fundamental
understanding of problems associated with intensive closed-
system fish culture. It is also concluded that waste heat-
augmented horticulture can be made commercially attractive
even in the Vermont winter climate. However, the parameters
affecting commercial success are many and varied and their
interactions sufficiently complex to justify investment in a
test of the greenhouse designs and the various heating
options before full-scale construction is undertaken.
Regarding impact of the Delaney Amendment, it was concluded
that both horticulture and aquaculture may operate com-
mercially at the Vermont Yankee station without intermediate
heat exchangers since station design and operating pro-
cedures provide sufficient barriers to radionuclides pro-
duced during normal operations. Moreover, these barriers
appear to be sufficiently redundant to provide necessary
consumer protection even during abnormal operating con-
ditions. Experimental programs will establish the validity
of these initial conclusions.
1.5 TEST PROGRAM IMPLEMENTATION
1.5.1 Fiscal Requirements
Capital investments of approximately $1.9 million
('77$) will be required for construction of the proposed
aqualab ($1.3 million) and the four-house test horticulture
complex ($600,000). Construction of the commercial fish
(trout) rearing facility is excluded at this time, although
land space allocation to accommodate such a facility will
remain part of the Vermont Yankee long-range waste heat
utilization plans.
1.5.2 Schedule
Implementation of the test program is planned in four
phases, extending somewhat beyond three years and commencing
as soon as preliminary design funding is available. Figures
1.10 and 1.11 are. time bargraphs, showing approximate
intervals and key points for events to occur, leading to
operation of each facility.
15
-------
The large triangles in the body of each bargraph
represent specific dates when positive assurance exists that
adequate funds are available to support the next phase. The
numbers represent the approximate number of months duration
of each phase. Horizontal arrows indicate possible time
period "stretch-outs" or indefinite termination dates. The
dotted vertical lines with arrows indicate when an intervening,
or follow-on, step should be introduced. For example, in
the first year completion of the Detailed Project Definition
must include an environmental impact assessment.
SCHEDULE - QUARTERS
:VENTS-AQUALAB
'HASE I
> Preliminary Design Funding V
3 Detailed Project Definition
3 Environmental Impact
Assessment and Other
Legal Requirements
D Budget Reevaluation and
Approval
=>HASE II
3 Engineering Design Funding
3 Detailed Engineering
Design
) Review and Approval
DHASE III
D Construction Funding
3 Bidding and Contract
Award
i Construction, Testing and
Acceptance
) Preparation of Systems
Management Manual
3HASE IV
) Facility Operation
1st Year
1234
7
'• t'
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IT"
^
F1 fmrp 1 . 1 0
2nd Year
1234
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7
1 11
d
^
JT
Aniifll ah nnnst-
3rd Year
31
7j
i
12
3 |
•mrl-'tnn SnVi^Hnl
4th Year
2 34
1 2 |
1 4 1
fa
16
-------
SCHEDULE - QUARTERS
EVENTS - HORTICULTURE
PHASE I
o Preliminary Design Funding \
o Detailed Project Definition
o Environmental Impact
Assessment and Other
Legal Requirements
o Budget Reevaluation and
Approval
PHASE II
o Engineering Design Funding
o Detailed Engineering
Design
o Review and Approval
PHASE III
o Construction Funding
o Bidding and Contract
Award
o Construction, Testing and
Acceptance
o Preparation of Systems
Management Manual
PHASE IV
o Facility Operation
1st Year
1234
7
'^^f
S
2nd Year
1 2 3 4
7
7
1 11
IT
\
[r
3rd Year
1234
T]
4
do
r
1 9
3 |
4th Year
1234
2 1
*-
Viorflii 1 o
While it is generally expected that both projects will be
undertaken concurrently, they could be undertaken separately,
provided that the aqualab is constructed first. This is
because the horticulture operation depends, in part, upon
sharing certain support components that must be constructed
for the aqualab.
17
-------
CHAPTER 2
HORTICULTURE PROGRAM
Kramer, Chin and Mayo, Inc,
Consulting Engineers
1917 First St.
Seattle, WA 98101
2.1 GREENHOUSES (Appendix C)
2.1.1 General
Thirty years ago a significant portion of the grocery
market in the Northeast was supplied by produce grown in
commercial greenhouses. In recent years, however, most New
England greenhouse industries have converted to specialty
foods and ornamentals. This has been a direct result of the
development of large, economically-refrigerated highway
freight systems. Today, high fuel costs are tending to
reverse the situation, and hot-house food production may
again be economical in New England if low cost space heating
can be provided.
2.1.2 Greenhouse Design
The basic greenhouse is about 18 x 8 meters (60 x 26
feet) and is designed with energy conservation in mind. The
design incorporates a shape and appropriate construction
materials that optimize the collection of solar energy while
reducing the heat loss from the structure.
The greenhouse has a large, south-facing transparent
surface (double-layered polyethylene) and an insulated north
wall with high light-reflective interior surfaces which
provide increased light levels. Basic design criteria are
as follows:
Temperature
o Winter design temperature outside = -26°C (-IS^F).
o Greenhouse inside temperature = 18°C (65°F) (day).
o Wastewater heat from power plant = 21°C (70°F).
Physical Criteria
o Insulation in north wall of greenhouse = R-16 (a measure
of thermal resistivity).
o South wall slope elevation = 38 degrees from horizon.
o Sunshine during winter = 40% of total theoretically
available.
19
-------
2.1.3 Service Building
In addition to the greenhouses, a 12 x 30-meter (40 x
100-foot) service building will provide space for research
offices and the greenhouse and methane generator support
facilities.
2.2 BIOGAS GENERATOR (Appendix B)
2.2.1 Process Description
Biogas generated from farm products, primarily manure,
consists of 60% methane gas and 40% non-combustible gases.
It would be generated by the following anaerobic digestive pro-
cess. Manure from dairy cows is delivered to the methane-
generating holding tank located on the plant site. It is
then fed into a premix tank where 16°C (60°F) water, heated
by the condenser discharge, is mixed with it to form a warm
slurry. Several variables, including temperature, organic
residence time and the solids retention period, affect the
volatility of the bacterial anaerobic fermentation process.
Since the temperature of barn-floor manure in winter may be
as low as 2°C (35°F), it must be warmed for the digestive
process to take place. If no external heat is applied, most
of the energy of the decomposing manure would be used to
maintain the natural reaction temperature of 35°C (95°F),
therby reducing gas production. However, by utilizing the
nuclear plant's discharge water to preheat the manure, the
efficiency of the bacterial fermentation process is in-
creased. This external heat source, plus the fermentation
process, would maintain a slurry temperature of approxi-
mately 18°C (65°F). This temperature, however, is below the
optimum for maximum biogas production.
From the premix tank the slurry is pumped through a
heat exchanger where it is further heated by a biogas-fueled
heater which raises the slurry temperature an additional
17°C (30°F). This additional heating brings the slurry to
the optimum fermentation temperature of 35°C (95°F). At
this temperature the slurry enters the digest2r where
fermentation to biogas takes place. The biogas is then
stored or burned in conventional gas heaters. Any excess
gas would be sold or used to heat other facilities. The
remaining solids are stored for later use as fertilizer.
2.2.2 Facilities
Facilities for the methane generator consist of a
manure-holding premix tank capable of holding 22 cubic
meters (800 cubic feet) of cow manure. This insulated,
rectangular concrete tank would be below ground and would
have a pumping system to provide a transfer of the slurry
from the premix tank to the slurry heater. The slurry
heater would be a methane-fired boiler located inside of a
concrete structure. The digester, located underground so as
to reduce heat loss, is sealed to prevent biogas from
20
-------
escaping. The volume of this tank will be approximately 140
cubic meters (5,000 cubic feet). Biogas would be pumped and
condensed in a nearby tank to assure more than a one week
supply of gas reserve. Service systems for the methane
generator as well as administrative needs are provided.
2.3 HORTICULTURE LAYOUT
Figure 2.1 is a plan view of the four greenhouses and
biogas generator test complex sited on Vermont Yankee
property. The ficility would be located on the northwest
corner of the property, outside the existing security fence.
Although this will require transporting the discharged
heated water about 1200 meters (0.75 miles), the site has the
advantage of close proximity to Vermont Route 142 and a
contiguous 200-animal dairy farm.
power plant site
horticulture
program
PROPERTY LINE
— * FENCE
VERMONT YANKEE
AQUACULTURE AND
HORTICULTURE ENERGY
PROGRAMS
VERNON, VERMONT
'Kfr/t' *•'""»•'• I*'' « M™. leu.
e.ufc'i-':".;
oru—i Sr
100 0 20O
2.1
Figure 2.1 Power Plant Siting of Horticulture Program
21
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CHAPTER 3
SUPPORT SYSTEMS
3.1 PUMP STATION
3.1.1
General
The pump station provides 0.53 m /s (8,390 gpm) of
ambient river water to the aquacultural and horticultural
facilities. It is located approximately 91.5 meters (300 feet)
upstream of the power plant intake structure in order to obtain
ambient river water (Figure 3.1). This is because of the
possibility of recirculation of plant discharge water back
to the plant intake structure during periods of prolonged
low river flow. A bar screen prevents large floating debris
from entering the pump house, while a traveling motorized
screen filters particles greater than 6-7 mm (1/4 inch) in
size. Four pumps of varying capacities are provided to meet
water pumping requirements and to provide redundancy for
partial pump system failures (Figure 3.2).
,V -^
, ..^ ^— oatm:*.
-^(-'••' F«OUi
power plant site
support systems
LEGEND
PROPERTY LINE
—* FENCE
• *• —M AMBIENT WATER LINE
• ••• i • PLANT DISCHARGE
WATER SUPPLY & RETURN
........... RAW & HEATED AMBIENT
WATER LINES
^*—"•—•* WAST£ LINES
VERMONT YANKEE
AOUACULTURE AND
HORTICULTURE ENERGY
PROGRAMS
VERNON, VERMONT
liO'1'**' Kr-nwT, <:hJn ft Mdiu. In.
100 0 300 400
Figure 3.1 Power Plant Siting of Support Systems Plumbing
23
-------
support systems:
pump station and
heat exchanger
RAW AMBIENT WATER
HEATED AMBIENT WATER
POWER PtANT DISCHARGE
WATER
WASTE WATER
VERMONT YANKEE
AQUACULTURE AND
HORTICULTURE ENERGY
PROGRAMS
VERNON, VERMONT
r. CUnlM.,., Inc.
f-Jffl
ruiJ 1 T
3.2
Figure 3.2 Support Systems: Pump Station and Heat Exchanger
Standby power will be provided from a generator in the
heat exchanger building. A bubbler system in the ambient
water intake structure will assure ice-free operation during
severe winter weather. The structure will be enclosed but
not heated. Cooling and/or ventilation will be provided
support system components to assure adequate equipment
operation. The pump station will be constructed of concrel
and concrete blocks.
3.1.2 Criteria
Maximum required discharge
Minimum required discharge
Intake Elevation
Discharge Elevation (approx.)
0.53mJ/s (8,390 gpm)
56.64m /s (2,000 gpm)
67.1m (220 feet)
82.35m (279 feet)
3.1.3 Facilities
Traveling screen for debris removal:
o Four pumps
One of 100 hp
Two of 50 hp
One of 15 hp
o Pumphouse building is approximately 7.625 x 0.66m
(25 x 35 feet) in size
24
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3.2 HEAT EXCHANGER BUILDING
3.2.1 General
The heat exchanger building would be located adjacent
to the power plant discharge structure. Water is pumped
from the power plant discharge structure and heat exchanged
through four plate surfaces rather than across cylindrical
surfaces as in "tube type" heat exchangers. The circulated
water is then returned to the discharge structure downstream
of the heat exchanger pumps.
Ambient river water from the pump station is pumped
through the heat exchanger, providing up to 0.50m3/s (8,000
gpm) of 16°C (60°F) water for the rearing of fish.
The purpose of a heat exchanger between the condenser
discharge water and the fish environment is to protect the
fish from chemicals added to the condenser water for fouling
and corrosion control. It also adds an additional barrier
against any radionuclides that may be in the primary (reactor)
coolant loop. Although the results of the regulatory study
(Appendix A) suggest that the heat exchanger will not be
necessary for commercial food production, it is planned to
include it in the operation of the test facilities (aqualab
and greenhouse complex). This will allow necessary comparison
studies to be performed for clearly establishing the
safety of food growing activities at the Vermont Yankee site
and the compliance with the Delaney Amendment.
3.2.2 Criteria
Temperatures;
Minimum river water 0°C (32°F)
Minimum discharge from power
plant 21°C (70°F)
Optimum rearing water 16°C (60°F)
Minimum rearing water for
Aqualab (boiler backup
water) 10°C (50°F)
Circulating boiler water 88°C (190°F)
Flows:
Maximum flow from power plant
discharge (El. 220') to
heat exchanger (El. 256') 0.63 mj/s (10,000 gpm)
Power plant discharge to
Aqualab 0.003 m°/s (50 gpm)
Power plant discharge to
methane generator and 3
greenhouse 0.016m /s (250 gpm)
25
-------
3.2.3 Facilities
o Four pumps at 50 hp
o Four heat exchangers at 27,984,000 BTU/hour
o One standby generator at 400 kva
o One steel, insulated building 163 sq. meters
(1,750 sq. feet)
When the power plant shuts down, standby boilers will.
supply the aqualab with 10°C (50°F) water. The heat exchanger
building will also house the standby generator to supply
power to the pumps during a power outage.
Construction of the heat exchanger building will
consist of a slab on grade with masonry walls. The roof
will be of insulated metal construction. This construction
technique will be compatible with the existing structures
and the Vermont climate. The building will not be heated
but ventilation will be provided for the proper functioning of
the equipment. Storage will be provided for maintenance
equipment. A monitoring and electrical panel vault will
also be housed within the heat exchanger building. Overhead
doors will permit the removal and replacement of heat
exchange elements within the building.
3.3 WASTEWATER TREATMENT FACILITIES
The aquaculture program will produce the following
types of wastewater:
1) Domestic
2) Hatchery/lab overflow
3) Hatchery/lab cleaning
Domestic wastewater will be treated through the use of
a septic tank and an underground drain field. Hatchery/lab
overflow wastewater will not require pretreatment prior to
discharge into a polishing pond*.
Hatchery/lab cleaning wastewater, however, will be pre-
treated prior to its introduction into a polishing pond.
The combined overflow and pretreated cleaning wastewater
will be of such quality that the total effluent discharged
from the polishing pond will meet all applicable state and
federal guidelines and regulations.
Overflow from the polishing pond will flow into the
Connecticut River via a natural drainage ditch.
Plant discharge water, supplied to the aqualab for
experimental use, will be returned to its source.
*A temporary water retention basin commonly used for final
(5%) clean-up of wastewater.
26
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The horticulture program will produce the following
types of wastewater:
1) Domestic
2) Greenhouse drainage
3) Digested sludge from the methane generator
Domestic wastewater will be treated by a septic tank and
drain field system. Drainage wastewater will be presettled and
introduced into a leaching field. An underdrain from the
drain field will be diverted to an existing ditch flowing
into the Connecticut River.
Stabilized sludge from the digester sludge lagoon will
be disposed of as fertilizer for direct land application.
Appropriate bacteriological and chemical analysis will be
performed as necessary on sludge prior to direct land
application.
3.4 ON-SITE AND OFF-SITE WORK
o Grading:
Little grading will be required since the site is
level and the facilities have been located to fit
the existing topography. Funds have been included
in the cost estimate for erosion control and for
some landscaping.
o Roadways:
Roads will be constructed to the aquaculture and
horticulture facilities. Access to the pump
station and the heat exchanger building will be
by existing roads.
Roadway Criteria
Materials: 0.05-meter (2-inch) thickness of
asphalt concrete paving over 0.23
meters (9 inches) of gravel base.
Widths: One-lane traffic 3.6 meters (12 feet)
Two-lane traffic 6.7 meters (22 feet)
Parking areas 13.1 meters (43 feet)
Drainage: Cross-drainage will be carried by culverts
No storm sewers are anticipated.
Lighting: Parking areas and entries will have
security lighting.
o Utilities:
Electric power and telephone lines are available at
the site. Major power services will be at the
pump station, heat-exchanger building, and horti-
culture facility. A well will be constructed
at both the aquacultural facility and the horti-
cultural facility.
27
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3.5 PLANT DISCHARGE WATER
Plant discharge water, taken from the power plant
discharge structure, is used as the heating medium for the
ambient water entering the heat exchangers, for heating the
manure required for the methane generator supplying supplemental
energy to the greenhouses, and for experimental purposes at
the aqualab. All removed plant discharge water is returned
to the power plant for discharge. All supply piping will be
insulated. The minimum temperature of the plant discharge
water is 21°C (70°F).
3.6 HEATED AMBIENT WATER
Heated ambient water is river water that is heated by
heat exchangers to 16°C (60°F). This water is used to
raise fish in both the aqualab and fish hatchery. All heated
ambient water piping will be insulated. When the power
plant is shut down, sufficient water to operate the aqualab
will be heated to 10°C (50°F) by oil-fired boilers.
3.7 RAW AMBIENT WATER
Raw ambient water is river water that is not heated.
The only treatment of the raw ambient water is debris screening
at the pump house. Raw ambient water is used at both the
aqualab and the fish hatchery for rearing fish and service
water.
3.8 WELLS
Two wells will be constructed, one near the aquacultural
facility and one near the horticultural facility. The
aquaculture well will be used only for potable water and
toilet facilities. The horticulture well will be used for
both potable water and service water for the greenhouses.
28
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CHAPTER 4
COST ESTIMATES
Kramer, Chin and Mayo, Inc.
Engineering Consultants
1917 First Street
Seattle, WA 98101
4.1 CAPITAL COSTS INCLUDING CONSTRUCTION
4.1.1 Purpose
The purpose of this preliminary cost estimate at the
conceptual stage is to provide initial cost information for
the construction program budget. It includes costs for all
items needed to complete all growing and test programs*. The
costs are based on 1977 dollars (or equivalent statement to
establish value of "dollars").
4.1.2 Cost Factors and Assumptions
Forty-year building life is assumed for mechanical
equipment systems, while 25-year design life is assumed for
building enclosures.
o Overtime:
No allowance has been made for overtime work.
o Weather Conditions:
Normal conditions are assumed. No consideration
has been given to unusual weather extremes.
o Labor:
Prices reflect the work being performed by one
licensed and bonded general contractor.
o Overhead and Profit:
The unit prices used include all labor, material
and equipment, and the overhead and profit of the
general contractor and subcontractors.
o Remoteness:
Due to the type of construction and proximity to
urban areas, the remoteness factor would be less
than one percent and is therefore not included in
calculations.
o Mobilization:
This item consists of furnishing all bonding,
licensing, plant, labor, materials and equipment
necessary to mobilize the contractor's equipment to
the project site and, upon completion of the work,
to demobilize the equipment from the site. Based
on experience, five percent (5%) of the construction
cost will be used.
*The Construction Cost Summary, Table 4-1, does not include design
services. Information for design services and cost allowances are
included in Table 4-2, item 12.
29
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Construction Contingency:
A ten percent (10%) contingency factor is used to
account for unforeseen conditions and changes
during the remaining engineering phases, also for
changes encountered during construction.
Design Services-Design Contingencies:
An allowance must be provided for design, construction
observation, operations and management manuals and
design contingencies. Due to the indeterminate
nature of the final design elements, only approxi-
mations can be made to indicate the range of costs.
Due to all elements being dependent to some
degree on the support systems, clear separation of the
programs with their portions of the cost of the
support systems is not reasonable at this time.
Therefore, it is recommended that preliminary
professional services costs and fees be determined
for the selected programs and that these then be
added to the construction cost estimates to determine
the project costs.
30
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TABLE 4-1
CAPITAL COSTS
(CONSTRUCTION COST SUMMARY)
SUPPORT SYSTEMS:
SITEWORK 107,110
UTILITIES 43,500
PUMP STATION 224,000
HEAT EXCHANGER BUILDING 629,800
SUPPORT SYSTEMS 258,300
WASTEWATER TREATMENT 140,000
1,402,710
AQUACULTURE PROGRAM
AQUALAB 415,300
COMMERCIAL FISH HATCHERY 786,000
~~ ~~ 1,201,300 "
HORTICULTURE PROGRAM
HORTICULTURE SERVICE
BUILDING 134,000
GREENHOUSES 40,000
METHANE GENERATOR 40,500
-214,500'
$ 2,818,510
MOBILIZATION 5% 140,930
CONTINGENCY 10% 281,850 + 422,780
$ 3,241,290
Cost estimate reflects a bid date of autumn 1977 and is related
to the Engineering News Record (ENR) Const. Cost Index of
2532 for Boston. It relates to a whole integral design
concept described within the text and drawings and is based only
on the drawings and details shown. Other uses of this
estimate (such as extrapolations or uses in part) can result
in misleading results.
31
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TABLE 4-2
CAPITAL COST ESTIMATE (1977 dollars)
(UNIT COSTS)
ITEM
1. Sitework
Grading
Erosion control
Soil treatment
Landscaping and
signs
Fencing
Pavement
Drainage
Site Lighting
2. Utilities
Wells
Septic tank &
drain field
WWT drain field
Electrical service
Telephone
QTY.
74,560
1.84
920
7,120
60
2
2
1
UNIT
TOT.
SF
ACRE
TOT.
LF
SF
LF
TOT.
TOT.
EACH
EACH
TOT.
TOT.
UNIT
COST $
.03
1300
8.40
7.00
24.00
5000
7500
COST $
31,470
2,240
2,390
8,000
7,730
49,840
1,440
4,000
107,110
13,500
10,000
7,500
12,000
500
43,500
3. Pump Station
Substructure and
superstructure TOT. 100,000
Mechanical
Gates TOT. 10,000
Travelling screen TOT. 70,000
Pumps TOT. 31,000
Piping & valves TOT. 11,500
Electrical TOT. 2,500
225,000
(continued)
32
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4.
5.
6.
7.
ITEM QTY.
Heat Exchanger Building
Building shell 4,275
Mechanical
Heat exchanger
Pumps, mounting &
installation (4)
Standby generator,
400 KV
Piping & Valves
Electrical
Furnishings & special
equipment
Aqua lab
Building shell 6,600
Mechanical
Piping & valves
Tanks
Electrical
Furnishings & special
hatchery equipment
Vehicles & rolling stock
Heating, ventilation,
air-conditioning
Commercial Fish Hatchery
Building shell 18,000
Mechanical
Piping & valves
Raceways 8
Electrical
Furnishings & special
equipment
Vehicles & rolling stock
Heating, ventilation
air— conditioning
Horticulture Service Building
Building shell 4,000
Mechanical
Piping & valves
Electrical
Furnishing & special
equipment
Vehicles & rolling stock
Heating, ventilation
air-conditioning
UNIT
SF
TOT.
TOT.
TOT.
TOT.
TOT.
TOT.
SF
TOT.
TOT.
TOT.
TOT.
TOT.
TOT.
SF
TOT.
EACH
TOT.
TOT.
TOT.
TOT.
SF
TOT.
TOT.
TOT.
TOT.
TOT.
UNIT
COST $ COST $
40.00 171,000
326,000
42,000
45,000
25,000
5,800
15,000
629,800
37.00 246,000
99,300
18,500
18,500
35,000
12,500
4,000
433,800
25.00 450,00.0
133,000
17,250 138,000
10,500
30,000
3.2, 500
12,500
786,000
25.00 100,000
5,000
9,000
5,000
12,000
3,000
134,000
(Continued)
33
-------
UNIT
ITEM QTY. UNIT COST $ COST $
8. Greenhouses
4 complete greenhouses
(See Appendix for cost breakdown) TOT. 40,000
40,000
9. Methane Generator
Structure TOT. 28,500
Mechanical
Piping & valves TOT. 10,000
Electrical TOT. 2,000
40,500
10. Support Systems
Plant discharge
water piping TOT. 68,700
Heated ambient
water piping TOT. 121,700
Raw ambient
water piping TOT. 49,500
Wastewater dis-
charge piping TOT. 8,400
Monitor & alarm systems TOT. 10,000
258,300
11. Wastewater Treatment
Pretreatment TOT. 60,000
Polishing pond 3,200 SF 2.50 80,000
140,000
12. Design Services and Contingencies
Based upon the conceptual system's preliminary construction
estimates above, the following is provided for guidance
in estimating project completion funding. Please note these
are approximations subject to final project definition and
scoping.
Design Construction O&M Manual
Program Element Allowance Allowance Preparation
- Support System
- Aquaculture
Program
- Horticulture
Program
- Special Services,
etc.
$150,000 $ 60,000 $ 50,000
145,000 50,000 70,000
40,000 10,000 20,000
75,000
Total
Allowance
$260,000
265,000
70,000
75,000
$410,000 $120,000 $140,000 $670,000
34
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4.2 OPERATION AND MAINTENANCE COSTS (Table 4-3)
The following estimate of operation and maintenance
costs is based on Fall 1977 prices. A mark-up for inflation
will be required when the construction date is known.
Other important factors of this estimate are:
o The 0 & M costs for the aqualab are for a
full year, while the costs for the hatchery
are for nine months.
o The estimated pumping cost for the aqualab
may be high. Additional engineering has
been done on the heat exchangers, which
indicates these costs may be about 25% too high.
o The maintenance costs include a facility
replacement cost equal to 2% of the capital
cost of the facility.
35
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TABLE 4-3
OPERATION & MAINTENANCE COSTS
.C C
•P O
.Q C -H
(OO4J
•H 6 *0
m i
>iJ3 O
H -P -H
0) C -P
X!O(0
W -H O -P
C H T3 g OJ
O -P O
CO-H— ' O SO *•" O EH
Water Pumping $ 27,000
(0.015/kwh)
Boiler Heating
Stand-by 11,000
20-Day Scram 37,500
Building
Utilities 3,000
Supplies
(incl. feed) 7,000
Insurance
(auto, fire, etc. ) 2,000
Maintenance @
2%/yr (vehicular,
building, etc.) 28,000
Labor
Manager 12,500
Assistants 10,500
TOTALS $138,500
$ 23,500
0
0
12,000
40,000
3,000
26,000
12,000
18,000
$134,500
$ 150
0
0
3,000
4,000
300
6,000
12,000
9,000
$34,450
$ 50
0
0
600
0
0
500
0
600
$1,750
$ 50,700
11,000
37,500
18,600
51,000
5,300
60,500
36,500
38,100
$309,200
36
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APPENDIX A
FEDERAL LAWS AFFECTING
VERMONT YANKEE WASTE HEAT PROJECT
H. Reed Witherby
Ropes and Gray
225 Franklin Street
Boston, Massachusetts 02110
37
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CONTENTS
Page
1. I - Food, Drug and Cosmetic Act 41
A. Scope of Food, Drug and Cosmetic Act 42
B. FDCA Statutory Scheme - An Overview 42
C. Regulation of Food Additives 43
i. Radioactivity 45
ii. Chemicals and Corrosion Products. ... 47
D. Other Food and Drug Provisions 49
2. II - EPA Restrictions and Permit Requirements 50
A. Aquaculture Regulations 50
B. Pollution Discharge Permits 51
3. Ill - NRC Licensing Requirements 52
A. Modification of Existing Use and Production
Permit 52
B. NRC Environmental Review 52
4. IV - Conclusions 53
5. References 55
39
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FEDERAL LAWS AFFECTING
VERMONT YANKEE WASTE HEAT PROJECT
The Vermont Yankee nuclear power plant at Vernon uses
water drawn from the Connecticut River to remove heat from
the reactor water across a condenser and discharge the
heated river water back to the river.
With funding from EPA and ERDA*, Vermont Yankee is
exploring the possibility of using this waste heat for
aquaculture or horticulture. The purpose of this appendix
is to investigate any obstacles under federal law to such
projected uses.
While there are some familiar federal requirements
(e.g., a pollution discharge permit for a fish hatchery),
the only significant source of concern, and the area in which
the federal grant agencies have expressed the most interest,
is the impact of the Federal Food, Drug and Cosmetic Act (1).
The analysis in this study indicates that this law should not
be an obstacle to the proposed projects.
I. FOOD, DRUG AND COSMETIC ACT
A threshold question for the viability of any waste
heat project at Vermont Yankee is raised by the_specter of
radioactivity from the nuclear plant contaminating the fish
or vegetables. Obviously an unhealthy product would totally
undermine what is intended as a public-spirited project; this
applies equally to lower-profile possible_contaminants such
as residue from the water pipes and cleaning agents used
to flush them. The analysis may be extended to consideration
of the composition of the river water itself, especially
of evaporation of water from the cooling towers when the
plant is on closed cycle. Also cooling tower drift
carries chemicals into the atmosphere. A product which
is unhealthy from any source could expose Vermont Yankee
to liability under basic state law, tort or contract
principles.
*Department of Energy (DOE)
41
-------
The healthiness of food products in interstate commerce
trade could be a problem (2). Vermont has a parallel but
not identical statute covering intrastate products, which
will be touched upon later. The application of the FDCA
requires some close legal analysis and some understanding
of the operation of Vermont Yankee and of the proposed
project.
A. Scope of the Food, Drug and Cosmetic Act (FDCA)
In general, the FDCA regulates unhealthy foods by
excluding from commerce foods deemed to be adulterated. A
threshold question is whether the planned project will be
within the interstate commerce clause, which generally has
broad reach. Although cases dealing with the interpretation
of "interstate commerce" under the FDCA all involve business
activity, "commerce" for the purposes of commerce power
need not be business activity (3). The "Court" held that
cattle ranging across state borders were within interstate
commerce even though the cattle were not driven across the
border, no instrumentality of interstate commerce was used,
and no commercial purpose was involved in the border
crossing. Fish introduced into the Connecticut River are
sufficiently analogous to the cattle (Reference 3) to
suggest that, even if the products of the Vermont Yankee Waste
Heat Project are not sold commercially, they could be
considered to be in interstate commerce.
B. FDCA Statutory Scheme - An Overview
Analysis of the effect of the FDCA on the Vermont Yankee
Waste Heat Project requires a general understanding of the
Act. This is not easily achieved, as the FDCA is made up of
different, sometimes overlapping legislation.
The first prohibition (dating from the Food and Drug Act
of 1906) is of food "bearing or containing any poisonous or
deleterious substance" (natural or added) which may render the
food injurious to health. Thus, if a particular batch of
fish or vegetables were contaminated so as to be unhealthy,
it would not be marketable. The burden is on the govern-
ment to prove that the particular food product, by itself,
poses a health hazard (4).
In 1938, the Food, Drug and Cosmetic Act introduced a
prohibition of "any poisonous or deleterious substance
added to food, except where such substance is required in
the production thereof or cannot be avoided by good manu-
facturing practice..."(5). This prohibition was interpreted
rigidly to ban all unnecessary substances which the govern-
ment could show to be poisonous or deleterious as such, even
though used in amounts which could not possibly render the
42
-------
product unsafe (although there was an extra-legal system
of informal use tolerances) (6,7). If an added unhealthy
substance was found to be necessary, the government was
supposed to set tolerance limits (taking into account
cumulative effects beyond the particular item of food
involved) within which the additions were considered safe.
The Pood Additives Amendment of 1958 has now limited this
category to "added poisonous or added deleterious substances
(other than...food additives)" (8). Since the comprehensive
definition of food additives includes poisonous or deleterious
substances except when added on an accidental basis (see
below) and since the accidental addition of poison is un-
likely to be considered necessary to, or unavoidable in,
food production, it is not clear whether this category retains
any viability; but see part I.D. below.
Finally, further prohibitions were incorporated by the
Food Additives Amendment of 1958. In general terms, this
amendment disallows the presence of additives in food, or the
subjection of food to radiation, without the blessing of a
Pood and Drug Administration regulation upon a petition in
which the applicant must demonstrate that the intended
use is safe under the proposed conditions. Further, the
1958 amendment introduced the so-called Delaney Clause,
flatly prohibiting the addition to food of any carcinogen
in any amount.
C. Regulation of Food Additives
The Food Additives Amendment of 1958 requires a Food
and Drug Administration regulation or exemption with respect
to any food additive, defined as:
any substance the intended use of which
results or may reasonably be expected
to result, directly or indirectly in
its becoming a component or otherwise
affecting the characteristics of any
food (including any substance intended
for use in producing, manufacturing,
packing, processing, preparing, treating,
packaging, transporting or holding
food; and including any source of radi-
ation intended for any such use), if
such substance is not generally re-
cognized, among experts qualified by
scientific training and experience to
evaluate its safety, as having been
adequately shown through scientific pro-
cedures (or, in the case of a substance
used in food prior to January 1, 1958,
through either scientific procedures or
experience based on common use in food)
to be safe under the conditions of its
43
-------
intended use (with certain exceptions
not presently relevant) (9).
According to the legislative history of the Food Additives
Amendment of 1958, this pr9vision
covers substances which are added intention-
ally to food. These additives are generally
referred to as "intentional additives". The
legislation also covers substances which may
reasonably be expected to become a component
of any food or to affect the characteristics
of any food. These substances are generally
referred to as "incidental additives" (10).
The legislative history also draws a distinction between
these "intentional" or "incidental" additives and "accidental-
additives". The latter are defined as "substances (which)
if properly used may not reasonably be expected to become
a component of food or otherwise affect the characteristics
of a food" (11).
The 1958 Amendment also requires a Food and Drug
Administration regulation or exemption for "intentionally
subjecting food to radiation" (12). There is no requirement
that radioactivity affect or become a component of the food.
The Food Additives Amendment accordingly requires a
regulation or exemption from the Food and Drug Administration
for the use of circulating water in the waste heat project
if subjection of fish or produce to radiation is intentional
or if any substances affecting the products are intentional or
incidental additives not generally recognized as safe.
Exemptions are available only for scientific testing.
Regulations are available only upon a petition in which the
applicant undertakes to establish, upon scientific data, the
safety of the proposed additive under the conditions of
proposed use (13). The key provision, containing the proviso
known as the Delaney Clause, is (14):
No such regulation shall issue if a fair e-
valuation of the data before the Secretary
fails to establish that the proposed use of
the food additive, under the conditions of
use to be specified in the regulation, will
be safe: Provided, that no additive shall
be deemed to be safe if it is found to induce
cancer when ingested by man or animal, if
it is found, after tests which are appropriate
for the evaluation of the safety of food ad-
ditives, to induce cancer in man or animal.
There is an exception to the proviso with respect to animal
feeds in that no additive residue will remain in the ulti-
mate food product. Although the practical situation of
some possible contaminants in the growing environment
projected here is certainly analogous, it is unlikely that
44
-------
this exception would apply here.
The Delaney Clause has come under considerable criticism
because it forbids the government to weigh the possible
public health benefits from low-level use of any substance
which is found to be carcinogenic under any conditions.
The scientific anomalies of this provision are explored in
reference 15.
i. Radioactivity
Much concern has been expressed during the development
of the waste heat proposals about the limiting effects of
the Delaney Clause with respect to the Vernon station's
nuclear character. It can be generally assumed that all
radioactivity is, at some level, carcinogenic. However, there
is no basis for concluding that radioactivity will become
a food additive at Vermont Yankee under the proposed cir-
cumstances.
The radioactivity at Vernon emanates from the nuclear
fission material at the core of the plant. It is predictable
that failures in the cladding of this material will allow
neutron emissions into the surrounding primary coolant,
causing small amounts of qualitatively less potent radio-
activity in that closed system. The plant is designed,
however, so that none of this radioactivity should get
into the circulating water. The exchange of heat between
these two systems in the condenser occurs through two thick-
nesses of pipe which allow no transfer of materials, and
would not be of a variety capable of causing any radio-
activity in the circulating water.
Moreover, instead of discharging this induced radio-
activity into the river (as permitted by the terms of its
Nuclear Regulatory Committee and Federal Water Pollution
Control Agency permits), Vermont Yankee has chosen to dispose
of it otherwise. Radioactive inert gases are bled from the
primary coolant and released into the atmosphere; radio-
active corrosion products are filtered out and transported
away for burial; and tritium is stored in tanks to decay.
Even if the plant were to discharge such items through its
"radwaste" system, that system is not mixed with the
circulating water system until the brink of discharge
into the river; that is, the water for the proposed projects
would be drawn out of the circulating water system at a
point prior to the entry of any discharge of radioactive
contaminants through the radiological decontamination system.
Thus, quite apart from the extra barrier which could be
provided by a surface type exchanger, it should be clear that
there will be no intentional subjection of the food to
radiation, making reference 16 inapplicable to the project.
The only way radionuclides could get into the water circulating
to the proposed projects would be from a failure in the condenser;
45
-------
such a failure would be unintentional; therefore, the
resulting possibility of exposure would be unintentional.
(The legal doctrine which in some contexts holds^someone to
"intend" the foreseeable consequences of his actions
would appear inappropriate here. First, the definition of
food additive expressly includes this variety of intention
in its coverage of "incidental additives", raising the inference
that the omission of an explicit inclusion here was intended
as an exclusion. Secondly, the statutory language (16)
prohibits "subjecting" the food to radiation, phrasing which
imports a positive act of directing radiation upon the
food.)
A similar analysis applies to the question whether
radioactivity could under any circumstances be an "intentional
additive" under reference 17. The statutory definition
includes "any substances the intended use of which results
or may reasonably be expected to result" in its becoming
a component of or affecting the food (18). It is Vermont
Yankee's clear intention not to expose the food to radio-
activity; under the conditions of its intended use, radio-
activity will not enter the circulating water at all.
Although the words of the statute may admit of some ambiguity,
the natural interpretation applied above is verified^by the
legislative history, in which "intentional additives" are
defined as "substances which are added intentionally to
food". Under the circumstances presented, radioactivity is
clearly not such a substance.
The question remains whether radioactivity might be an
"incidental additive", that is, a substance "which may
reasonably be expected" to become a component of or affect
the fish or vegetables. The legislative history contrasts
such included substances with "accidental additives", sub-
stances which "if properly used may not be reasonably
expected to become a component..."(19) (emphasis added).
Proper functioning of the Vernon plant, as it is designed,
will not result in the presence of radioactivity in the
circulating water. Any introduction of radioactivity
into the water would be the result of a failure in the
system. Thus under this definition, radioactivity could
not be an "incidental additive".
The statutory standard of reasonable expectation is to
some extent a function of probabilities. Thus, if experience
at the plant showed that failures in the condenser were
frequent, so that it was reasonable to expect the presence
of radioactive contamination in the circulating water, then
further steps of analysis concerning heat exchangers, whether
exposure would result in contamination, and possible
general recognition of safety could be necessary. However,
the experience of the Vermont Yankee plant has been that
over five years of operation only one leak of radioactivity
into the circulating water has occurred (due to the rupture
of a gasket in March, 1977). This statistic supports the
conclusion that any presence of radioactivity in the
46
-------
circulating water would properly be considered an accident
rather than an incident to proper operation.
Thus, it should be concluded without further analysis
that radioactivity from the plant will not be a "food additive"
with respect to any of the products of the proposed projects.
(However, the analysis considered below with respect to
chemicals could also be applied: e.g., the presence of heat
exhangers would reduce considerably the statistical probability
of exposure, supporting the determination that any radioactivity
would be an "accidental" additive. Moreover, it is understood
that at least tritium would pass through rather than ac-
cumulate in fish, etc.) The situation at other nuclear plants
may be different. For example, the Northeast Utilities
plant at Millstone (intentionally) discharges its radioactive
wastes into the growing environment of its mariculture
experiment. The application of the "food additives" provision
to that situation (apart from the possible lack of inter-
state commerce) would appear to turn primarily upon whether
the resulting concentrations of radioactivity in the oysters
produced could be shown to be generally recognized as safe
by scientific experts. (The highest concentrations measured
at Northeast Utilities, under circumstances more likely
to produce high concentrations than would similar dis-
charges at Vermont Yankee, were on the order of a few
percentage points over background; therefore, given the
variation in background radiation from place to place, these
concentrations are probably well below those naturally
occurring in much of the food that we eat (20). The fact
that the Delaney Clause would prohibit the Food and Drug
Administration from finding radioactivity to be safe within
any tolerances with respect to authorizing its use as a
food additive does not legally affect the analytically
prior determination of whether it is generally recognized as
safe under the conditions of its intended use; because if
it is so recognized, it is not a food additive and therefore
does not come under the Delaney Clause.
ii. Chemicals and Corrosion Products
Two categories of substance are added to the river
water as it circulates through the Vernon plant and
will be contained in the circulating water which is drawn off
to the proposed projects. These are (a) chemicals added as
cleaning agents, demineralizers, biocides and corrosion
controllers and (b) corrosion products from the pipes
through which the water runs. Will these constitute _
"food additives" requiring a Food and Drug Administration
regulation?
The legislative history uses as an example of accidental
additives "paints or cleaning solutions used in food processing
plants". This example may appear virtually on all fours with
the chemicals used at Vermont Yankee since their purpose is
47
-------
analogous to cleaning solutions. However, at Vermont Yankee
the chemicals are added intentionally to the very circulating
water which will carry the heat to the project and, absent
heat exchangers, will come into direct contact with the food.
Indeed, it is partly because of the potential deleterious
effects of such direct contact that biologists working on the
aquaculture project have recommended the use of heat exchangers.
Assuming that such contact would result in chemicals be-
coming a component or affecting the characteristics of the
resulting food product (.which seems likely) , the next
question would be whether such chemicals could be shown_
to be "generally recognized as safe" under these conditions.
Presumably this' determination would vary with respect
to Vermont Yankee's use of particular chemicals. (Cf. EPA
effluent limitations as to steam generating nuclear plants...
reference 21.) However, general recognition of safety under
conditions of intended use is not easily satisfied, requiring
a consensus of experts based upon scientific testing or
(as to substances used in food prior to 1958) upon experience
based upon common use in food.
Without heat exchangers, the "generally recognized as
safe" standard would also have to be satisfied with respect
to pipe corrosion residues. (This item highlights the
impact of advancing technology which now can measure small
amounts that would have gone undetected only a few years
ago.) This material is not intentionally added to the
circulating water, but it should reasonably be expected to
get into that water in small quantities, even under normal
and proper use of the plant. If this results in its becoming
a component of or affecting the food, only a general recognition
of safety would prevent it from being a food additive.
Perhaps as to some of the chemicals or corrosion products,
some testing has occurred (reference 22) or perhaps it could
be determined that greenhouse or hatchery operations pre-
dating 1958 introduced the same substances to their products,
constituting an identifiable experience of common use upon
which a scientific judgment of safety could be based. If
not, and if no heat exchangers are used, it would appear
to be necessary to conduct tests and (unless the tests
gave rise to a "general recognition of safety") to seek
a Food and Drug Administration regulation setting conditions
for use. The alternative to this is to use heat exchangers.
Heat exchangers change the "food additives" analysis by
constituting a barrier between the circulating water and
the growing environment, a barrier which may, in addition,
be pressurized to cause any leaks to be directed away from
the food environment into the circulating water. Since the
purpose of such a barrier includes such protection, it may
be said with confidence that neither the chemicals nor the
corrosion products would be reasonably expected to be
48
-------
exposed to the food and, therefore, that they would not be
"food additives" within reference 23. (This would apply also
to any radioactivity which found its way into the circulating
water, whether expectably or not.) It is understood that
heat exchangers are projected for the entire aquaculture
project and contemplated for three of the four greenhouse
designs. Moreover, the remaining greenhouse ("Rutgers1 Design")
is, for environmental reasons, being recommended for raising
ornamental plants rather than food plants, and the lack
of a heat exchanger there would be of no legal significance
if that recommendation is followed.
In sum, given the presence of heat exchangers isolating
the circulating water from each proposed food-growing
environment, none of the items under consideration would be
"food additives" requiring a Food and Drug Administration
regulation.
D. Other Food and Drug Provisions
In distinguishing accidental additives from intentional
and incidental additives, the legislative history of the
Pood Additives Amendment states that "if accidental additives
do get into food, the provisions of the (FDCA) dealing with
poisonous and deleterious substances would be applicable"
(24). In sections of the FDCA which mention "poisonous
and deleterious substances" are those (referred to in the
overview above) which predated the 1958 Amendment.
Food containing substances which are poisonous or
deleterious such that it may be injurious to health is
adulterated (unless the substance is not "an added substance"
and the quantity of the poisonous or deleterious substance in
the food does not ordinarily make it injurious to health) (25).
Thus, a specific batch of actually unhealthy food would be
covered.
The section of reference 26 which provides that an added
substance (other than a food additive) which is poisonous
or deleterious is safe only if, under reference 27, the
substance is "required in production (of food) or cannot be
avoided by good manufacturing practice", and then only
pursuant to tolerances established by the Food and Drug
Administration (28). It could be argued in this respect that
the use of a heat exchanger was required in the waste heat
project as "good manufacturing practice" under the circumstances.
Although a heat exchanger is expensive, it is readily available
technology which could prevent addition to fish or produce
substances, including radioactivity, biocidal chemicals and
corrosion inhibitors, which might otherwise result in
adulteration. If so, the use of heat exchangers could be
required in order to avoid the prohibition of reference 27
as to any substances which might accidentally get added to
the food.
49
-------
Assuming the presence of heat exchangers, however, there
could still be failures which allowed, toxic chemicals
into the growing environment. If as a result traces of such
cnemicals^ound^heir way into the food the ^"1 terms
of reference 27 would prohibit the introduction of that food into
interstate commerce without the existence of a tolerance
promulgated by the Food and Drug Administration. Presumably,
at this point, some practicability of approach may take
over for de minimis additions; the Food and Drug Administration
also has a~syTEim~o"f informal tolerances under this section
(29) It should be remembered that this section applies only
to added substances which are poisonous or deleterious.
Other provisions of the FDCA declare food which is filthy
or decomposed, or the product of a diseased animal, or thV, <__
like to be adulterated. These prohibitions would be relevant to
the actual day-to-day operation of the project, but do not
present limitations upon the design of the project.
Consideration should also be given to the possible
presence of contaminants in the upstream river water which
is contemplated as the heat carrier to the growing environ-
ment if heat exchangers are used. It has been held that
mercury in swordfish is an "added substance" within the
meaning of reference 25 on the theory that it does not
occur naturally in the fish, but is acquired through its
external food supply (30). Similarly, the presence in
fish of DDT has been held to support seizure, once the
fish were smoked, as a food additive (31). Pesticides on
raw agricultural products are governed separately under
the FDCA (31), and tolerances have been promulgated (32).
Vermont's Labeling of Foods, Drugs, Cosmetics and
Hazardous Substances Act (33) prohibits the adulteration of
any food within the state (34). Adulterated food is defined
in reference 35 in terms parallel to the FDCA prior to the
1958 Amendment. Thus, food is adulterated if it contains
•^*^ . .. 1 _ * 1_ —. _ _ ~* A BA -J .M. *** 1 ^-
lyoo Amendment. J.AIUO, *.\j\^^. -«-•-• —.~.~*— — — -
a poisonous or deleterious substance which may render it
injurious to health. If the substance is added, it adul-
terates the food unl
which case the state e»«i-it>-»iJ.«.^*-«-' «-..———— f ^
(36). This act should not apply to the extent that pro-
_ • . _ _ *» ^ • _i___J _i_L ^l« j-^ ^P ^^^^ ^
injurious -f,-^— .—• — — . ( _
terates the food unless it is required in production, in
which case the state authorities should promulgate tolerance
(36). This act should not apply to th^ extent that pro-
visions of it conflict with the FDCA.
II. EPA RESTRICTIONS AND PERMIT REQUIREMENTS
A. Aguaculture Regulations
One section (37) authorizes the Administrator of the EPA
"to permit the discharge of a specific pollutant or pollu-
tants under controlled conditions associated with an
approved aquaculture project under Federal or State supervision
Subsection (b) of Section 318 empowers the Administrator
to establish procedures and guidelines which he deems
necessary to carry out Section 318 (37). The EPA has pro-
mulgated regulations pursuant to this provision (38).
50
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These regulations do not apply to the Vermont Yankee
aquaculture project. The scope of the aquaculture regulations
is limited "to those projects which are located in navigable
waters..." (39). The regulations defined "aquaculture
project" as "a defined managed water area which uses
discharges of pollutants into the designated project area"
(40): "designated project area" is in turn defined as
"those portions of the navigable waters within which the
applicant...proposes to confine the cultivated species"
(41). Also, the Supplementary Information accompanying
the promulgation of the regulations states that "aqua-
culture activities not covered by these regulations
-are those facilities operated in ponds, silos, and other
structures not within the navigable waters." (38). The
Vermont Yankee hatchery is to be located in a separate
building outside the Connecticut River, and therefore
falls within the category of "structures not within navigable
waters", and is not subject to the requirements of a permit
under Section 318 of the FWPCA.
B. Pollution Discharge Permits
Section 402 of the Federal Water Pollution Control Act
(FWPCA) (42) establishes the National Pollutant Discharge
Elimination System (NPDES). This provision authorizes the
Administrator of the EPA, or, where applicable, the
appropriate state permit-granting authority, to issue a
permit for the discharge of any pollutant into navigable
waters, provided doing so meets statutory conditions (43).
Although "approved aquaculture projects11 are excluded
from this requirement (44), other "discharges from an aquatic
animal production facility" are specifically included in
the requirement of an NPDES permit (45) . Since the present
project is not subject to regulations governing aquaculture
projects but is involved in production of aquatic animals,
it would constitute a point source from which the discharge of
pollutants requires an NPDES permit. A pollutant within
the meaning of the FWPCA includes, inter alia, solid waste,
chemical waste, biological materials, radioactive materials,
and heat (46). Since the fish tanks would discharge heat,
fish waste and food residues (and possibly contaminants from
the circulating water-system) into the Connecticut River, an
interstate waterway, the aquaculture project involves dis-
charge of pollutants into navigable waters and requires a
permit. As the result of an agreement between the EPA and State
of Vermont, the NPDES program administration is delegated to
the Department of Water Resources of the Vermont Agency of
Environmental Conservation (47). Full guidelines for state
permit requirements are set out (48).
51
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III. NRC LICENSING REQUIREMENTS
A. Modification of Existing Use and Production Permit
Vermont Yankee must obtain modification of its NRC license
in order to use its waste heat in either project, if this
use is inconsistent with procedures described in the facility's
safety analysis report to the NRC, if the change in the
disposal of circulating water does involve a change in the
technical specifications incorporated in Vermont Yankee's
license, or if the change presents an unreviewed safety
question (49). The change will be deemed to present an
unreviewed safety question if it will increase the pro-
bability of the occurrence or the consequences of an accident,
or if it creates the possibility of an accident or a mal-
function of a different type than any previously evaluated (50).
Vermont Yankee nevertheless would be required to maintain
records of the changes to the facility and resultant
changes in procedures and to prepare a written safety
evaluation of the change demonstrating that the latter does
not present an unreviewed safety question. A description of
the change and the safety evaluation must be furnished to
the NRC Regional Office (51). It would appear that a change
in the specifications of the circulating water discharge
system will require a license amendment even if Vermont Yankee
sees no safety problem, because the activity affects the
environmental technical specifications.
B. NRC Environmental Review
The National Environmental Policy Act of 1969 requires
all Federal agencies to prepare detailed environmental impact
statements on major federal actions affecting the quality of
the environment (52). The NRC's policies and procedures for
such environmental review in connection with the agency's
licensing and regulatory activities are set out in reference
53. These regulations require preparation of an environmental
impact statement in connection with, inter alia, any action
which the Commission determines is a major Commission action
significantly affecting the quality of the hui.ian environment (54)
Included among actions considered to be major Commission actions
significantly affecting the quality of the human environment
is any permit or license amendment which "would authorize a
significant change in the types or significant increase in
the amounts of effluents..." (55).
The FWPCA vests primary jurisdiction for the control of
water pollution in the Environmental Protection Agency (56).
Recognizing this, the NRC requirements for environmental
review are made subject to the limitations contained in an
interim policy statement published (57). This "second
memorandum of understanding and policy statement" states
that with respect to water quality standards, maximum daily
limits for pollutants and thermal limits the NRC will not
impose different limitations or requirements as a condition
52
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to any permit or license from those imposed by environmental
agencies, although the NRC did reserve the option to impose
more stringent limitations or requirements than those imposed
pursuant to the FWPCA. In addition, the NRC declaration of
policies states that no alternative pollutant discharge
systems will be considered by the Commission where a permit
has been received or effluent limitations imposed pursuant to
the FWPCA. Thus, with respect to pollution control considera-
tions stemming from the aquaculture project, it appears
that the NEC's environmental review yields to NPDES permit
requirements, even where the NRC might otherwise impose more
stringent standards.
The NRC, however, considers effluent limitations for
nuclear material to remain within its primary jurisdiction.
NRc's environmental review of any change in the Vermont Yankee
discharge system may therefore be required. Although the
aquaculture and horticulture projects will not result in
any additional radiological discharge, the proposed uses of
condenser effluent may result in hazards from the accidental
discharge of effluents into unrestricted areas not previously
reviewed by the NRC. It therefore seems advisable to seek
NRC's review. Such review will not necessarily require filing
of an environmental impact statement. If, upon evaluation of
the proposed action, the NRC determines that an environmental
impact statement need not be prepared, it may issue a
"negative declaration" explaining why an environmental
impact statement is not required and that a general environmental
appraisal will be made (58).
IV. CONCLUSIONS
Since the use of nuclear power plant waste heat for
aquaculture and horticulture is very recent, there is little
law which directly establishes standards applicable to the §
Vermont Yankee Waste Heat Project. The requirements affecting
the project are chiefly case-by-case permit requirements of
the Environmental Protection Agency and the Nuclear Regulatory
Commission.
The planned discharge of pollutants into the Connecticut
River will require a National Pollutant Discharge Elimination
System permit from Vermont authorities. This will be a "new
source" and therefore requires environmental review. Amendment
of Vermont Yankee's Nuclear Regulatory Commission license will
be required because of the detailed specifications in that
license for discharging circulating water.
The precise application of the Food, Drug and Cosmetic
Act depends largely upon whether surface heat exchanger systems
are used and, if they are not, upon the probability that the
circulating water will contain potentially unhealthy substances.
If heat exchangers are used, as is generally contemplated, the
53
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FDCA will not apply unless food accidentally becomes
contaminated with poisonous or deleterious substances. If
heat exchangers are not: used, the Delaney Clause setting zero
tolerance levels for carcinogens will still not be implicated to
the extent that contamination is not to be expected, despite
the fact that Vermont Yankee is a nuclear station; but a re-
gulation or control may be required for certain chemicals or
pipe residues contained in the cooling water. The Food,
Drug and Cosmetic Act also is implicated if particular food
produced at the project becomes contaminated so as to present
a health hazard.
54
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REFERENCES
1. Federal Food, Drug and Cosmetic Act, 1938.
t
2. Ibid, 21 USC § 301 et. seq.
3. Maryland v Wirtz, 269F. Supp. 826, 832-33 (D.Md. 1967),
affd 392 U.S. 183 (1968) and Thornton v. United States
271 U.S. 414, 425 (1926).
4. Federal Food, Drug and Cosmetic Act. § 342(a)(l). See
United States v. Lexington Mill & Elevator Co., 232
U.S. 399 (1914).
5. Ibid. § § 342(a)(2)(A), 346.
6. Markel, The Food Additives Amendment of 1958, 14 The
Business Lawyer 514 (1959).
7. United States v Ewig Bros. Co., 502 F. 2d 715 (7th Cir.1974)
8. Federal Food, Drug and Cosmetic Act. § 342(a)(2)(A).
9. Ibid, 21 USC § 321(s).
10. S. Rep. No. 2422, 85th Cong., 2d Sess., 1958 U.S. Code
Cong. & Admin. News 5303-04.
11. Ibid. 5304.
12. Federal Food, Drug and Cosmetic Act. 21 USC § 342(a)(7).
13. Ibid, § 348 and 21 C.F.R. Part 171.
14. Ibid, § 348(c)(3).
15. The Delaney Clause: Technical Naivete and Scientific
Advocancy in the Formulation of Public Health Policies,
62 California Law Review 1084 (1974).
16. Federal Food, Drug and Cosmetic Act, § 342(a)(7).
17. Federal Food, Drug and Cosmetic Act, § 321(s) and 342(a)(C).
18. Ibid. s 321(s).
19. S. Rep. No. 2422, supra, at 5304.
20. Cf. Section 1412 of the Public Health Service Act, as
amended by the Safe Drinking Water Act, 42 USC § § 300 g-1,
300 g-3, 300 j-4 and 300 j-9 and the EPA national interim
primary drinking water regulations, 40 C.F.R. Part 141.
21. Cf. EPA, 40 C.F.R. Part 423, 423.1KJ) proposed EPA effluent
standards for toxic pollutants under 33 USC 1317 (a) (1),
38 Fed. Reg. 35388 (1973).
55
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REFERENCES
22. Ashley, G.C. & J.S. Hietala. The Sherco Greenhouse:
A Demonstration of the Beneficial Uses of Waste Heat.
Proc. of Conf. on Waste Heat Management & Utiliz., 5/9-11, 1977,
Miami Beach, Fl.
23. Federal Food, Drug and Cosmetic Act § 342(a)(2)(C).
24. S. Rep. No. 2422, supra, at 5304.
25. Federal Food, Drug and Cosmetic Act § 342(a)(1).
26. Ibid. § 342{a)(2)(A).
27. Ibid. § 346.
28. FDA. Sec. 21 C.F.R. Part 122.
29. United States v. Ewig Bros. Co. 502 F.2d, 715, 720 (7th
Cir. 1974).
30. United States v. An Article of Food Consisting of Cartons
of Swordfish, 395 F. Supp. 1184 (S.D.N.Y. 1975) but see
Note 85 Harv. L. Rev. 1025 (1972).
31. Ewig Bros, supra. Pesticides on raw agricultural products
are governed separately under the FDCA, see § § 342(s)(2)(B),
and 346(a).
32. 21 C.F.R. Part 193.
33. Vermont's Labeling of Foods, Drugs, Cosmetics and
Hazardous Substances Act, Title 18 V.S.A. § § 4501 et seq.
34. Ibid. § 4502.
35. Ibid. § 4059.
36. Ibid, g 4062.
37 Federal Water Pollution Control Act, Section 318, 33 USC,
§ 1328.
38. 42 Fed. Reg. 25,478 (1977) to be codified at 40 C.F.R.
§ 115.1 et seq.
39. Ibid. § 115.2(d).
40. Ibid. § 115.l(d).
41. Ibid. § 115.l(e).
42. Federal Water Pollution Control Act, Section 402, 33 USC.
§ 1342.
43. Ibid. 33 USC § 1342(a)(1), (b).
56
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REFERENCES
44. 40 C.F.R. g § 124.21(c) and 125.4(c).
i
45. 40 C.F.R. 124.21(g)(2) and 125.4(1) (2), as amended,
41 Fed. Reg. 28496 (1976).
46. 33 USC § 1362 (6).
47. 2 State Water Regs. 93:0581 (BNA) (1974).
48. 40 C.F.R. | 124.1 et seq.
49. 10 C.F.R. § 50.59(a)(l).
50. 10 C.F.R. § 50.59(a)(2).
51. 10 C.F.R. § 50.59(b).
52. 42 USC § 4332.
53. 10 C.F.R., Part 51.
54. 10 C.F.R. § 51.5(a)(10).
55. 10 C.F.R. § 51.5(b)(4).
56. 33 USC § 1251 (d).
57. 40 Fed. Reg. 60115 (1975); cf. 10 C.F.R. 51.1(c).
58. 10 C.F.R. s 51.5(c)(l).
0
57
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APPENDIX B
WASTE HEAT BOOSTING
FOR ANAEROBIC FERMENTER
EFFICIENCY IMPROVEMENT
William J. Jewell
Thomas D. Hayes
Cornell University
Ithaca, New York 14853
59
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CONTENTS
Page
Background ......................... 65
historical Aspects ..................... 65
Estimate of Agricultural Residues .............. gg
ermenter Design
69
Production Potential gg
of Methane Generation System
- -»,_ww V^A.J e-/i+-«ar»4- •! al _ _ _
Recommendations 71
Estimated Cost of Methane Generation System 70
JJ®at Recovery Potential 70
to Appendix B
^aerobic Fermenter Design for a Dairy Farm of 200 Cows. . . 75
I. Estimation of Agricultural Residues 75
II. Fermenter Design 76
III. Digester Heating Requirements 76
IV. Digester Gas Yield Estimates 78
V. Holding Pond 79
Deferences 81
61
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FIGURES
Page
Flow diagram of feed, milk production and
waste materials on a 100-cow, free-stall dairy. ... 68
Digester location to nuclear plant premix tank
and storage holding pond 72
Holding pond and unloading pump location 73
TABLES
Page
Waste Composition gg
Dairy Cow Manure Production and Characteristics ... 57
Characteristics of Anaerobic Fermentation Process . .
63
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WASTE HEAT BOOSTING FOR ANAEROBIC FERMENTER
EFFICIENCY IMPROVEMENT
Background
Bioconversion of photosynthetically fixed solar energy in
existing agricultural residues has been projected to be capable
of generating about one quad annually.* The obvious attraction
of this possibility is that this is a clean renewable source of
energy which would make use of animal wastes and other materials
which have a pollutant creating potential. Energy farming has
the capability of adding another 10 quads while generating
several million tons of new protein in the form of bacterial
cells. There are two objectives in this experiment. First, to
examine the possibility of improving the rate of fermentation of
animal residues by preheating the fermenting slurry with Vermont
Yankee condenser discharge water and second to determine the eco-
nomics of using the methane gas generated in the fermentation pro-
cess as a substitute fuel for space heating. Technology for the
generation of methane by animal residue fermentation has been de-
veloped for very large cattle operations (1000 animals or more),
however, little work has been done on the development of economi-
cal anaerobic digesters for small scale farming applications (200
animals or less). Much of the quantitative data for these analyses
has been reported in Jewell et al. (1976).
Historical Aspects
Anaerobic fermentation has been applied to sewage solids
for digestion and stabilization for decades. However, until
recently it has not been applied to animal wastes. To the best
of these authors' knowledge, the first full scale methane
generation system in the U.S. was built by a private company in
Michigan in 1974. Presently, the U.S. DOE is involved in several
large scale efforts to demonstrate the feasibility of adapting
this technology to agriculture. A 3-million dollar demonstra-
tion plant is now under consideration for a 10,000-head beef
feedlot operation, and Cornell University has been given
authority to demonstrate the technology for dairies at its re-
search facility in Harford, New York under the direction of
William J. Jewell.
In general, methane fermentation of agricultural residues
appears to be justified only in large scale operations (greater
than 1000 head) if the net methane produced is the only benefit
attributed to the system. Other potential benefits include:
1. Conservation of nutrients
2. Labor reduction
3. Odor control
4. Runoff control
*0ne quad is equal to 1015 BTU.
65
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It can be shown that when pollution control is needed with a
liquid manure handling system, and all gas can be utilized, the
fermentation system can generate energy at a very low cost even
in dairies with 40 cows. The feasibility is site specific in
the present state of knowledge.
Estimate of Agricultural Residues
One agricultural operation is located close to Vermont
Yankee Nuclear Power Corporation's Vernon plant. This is
Mr. Paul Miller's dairy which appears to be one of the most
well operated, medium scale (200 cows) dairies in the Northeast
U.S.
Table 2 summarizes the dairy manure production compo-
sition. These estimates assume that the waste is removed
efficiently on a daily basis and that the animals are confined
100 percent of the time. Although Mr. Miller does not include
the milking room wastewater, it would be possible to include
this in the wastes. Bedding material used on the Miller dairy
includes hay and limestone. If the manure was to be used in a
fermenter, the use of limestone may cause some material handling
problems and handling may have to be modified. Limestone is
most often used to prevent animals from slipping on concrete
surfaces.
The make-up of a dairy that would have about 100 milking
cows at any one time would have the characteristics illustrated
in Figure 1. The average daily waste composition is as
follows for this size of operation:
TABLE 1
WASTE COMPOSITION
kg/day
Total solids (87.8% water by weight) 8240
Total dry solids 1000
Volatile solids (82% total) 840
Total nitrogen 34
Ammonia nitrogen 18
Phosphorus 13
Potassium 29
The Miller farm has 200 cows with a capability for increasing
its numbers up to double the above residue quantities, depending
on the total numbers of animals on the farm. Note that the above
values for the 100-cow dairy actually represent the residue genera-
tion from 163 cows, with only 100 being milked at any given time.
Other sizes of dairy operations can be scaled up from these data.
66
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TABLE 2
DAIRY COW MANURE PRODUCTION AND CHARACTERISTICS
(based on 1,000 pound liveweight)
Parameter
Manure Production
Density
Total solids
Volatile Solids
BCD5-day
COD
Total Nitrogen
Ammonia Nitrogen
Total Phosphorus
Potassium
Unit
kg/head/day
(Ibs/head/day)
-
(Ibs/ft3)
% TS
kg/head/day
{ Ibs/head/day)
fa TS
kg/head/day
(Ibs/head/day)
kg/head/day
(Ibs/head/day)
kg/head/day
(Ibs/head/day)
% TS
kg/head/day
(Ibs/head/day)
kg/head/day
(Ibs/head/day)
% TS
kg/head/day
(Ibs/head/day)
% TS
kg/head/day
(Ibs/head/day)
Total Excrement
Avg.
38.6
(85)
0.97
(60.6)
12.5
4.61
(10.6)
82
3.9
(8
•95
.7)
0.700
1.55
10.6
3-9
0.19
(0.41)
0.10
(0.23)
1.5
0.073
(0.16)
3.3
0.16
(0.35)
Range
32.2-49.9
(71-110)
0.94-1.00
(56.6-62)
3.08-6.76
(6.8-14.9)
3.27-5.76
7.2-12.?
0.44-0.83
0.98-1.84
2.63-7.26
5.8-16
0.16-0.28
0.35-0.62
0.032-0.18
0.07-0.39
0.068-0.22
(0.15-.4S)
67
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Feed
32-55 Ib/cow/day
Water
28-35 gal/cow/day
Bedding
•^•^••a—•"•""—^—g"
1.5-2.5 Ib/cow/day
100-Cow Free-Stall Dairy
with Milking Center
100 milk cows
60 replacement cows
3 bulls
Milk Products
20-55 Ib/cow/day
2.3-5.8 gaI/cow/day
Wastes;
Manure: 85 lb/1000 Ib/cow/day
Milking Center: 33.8 Ib/cow/day
Bedding: 1.5 Ib/replacement
cow/day
Feed: 2.5 Ib/milk cow/
day
1.5 Ib/cow/day
Figure 1. Flow diagram of feed, milk production, and waste
materials on a 100-cow, free-stall dairy.
68
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Fermenter Design
The bacterial anaerobic fermentation process is a complex
process. Many variables such as temperature, organic residence
time, and solids retention period affect the feasibility of the
process. One set of design criteria which would be successful
when applied to dairy wastes is as follows:
Table 3
Characteristics of Anaerobic Fermentation Process
Waste volume generation rate for 100-
milking cow operation
Premix tank volume
Pumping rate (about)
Reactor Design
Hydraulic retention time
Temperature
Solids loading rate
Total solids entering system
Tank volume
Energy Production
Volatile solids destruction
Gas produced
Methane content
10.1 m3/day (356.5 ft3/day)
20 mj (706 ft3) *
0.2 m /min(3 gpm)
10 days
35°C (95°F)
8.3 kg/m3-day
(0.5 Ib/ft3-day)
10% of slurry volume
124 m3 (4377 ft3)
32% of slurry volume
223 m-Vday (7872 ft3/day)
65% of slurry volume
Energy Production Potential
As indicated in Table 3, the process operates at 35°C
(95°F). Thus, in cold weather when the feed is coming into the
reactor at 0°C (32°F), a substantial portion of the energy
that is produced must be used to maintain the reactor temperature,
The total production for the 100-cow dairy is estimated to be
between 500 x 106 and 600 x 106 Real/year. The energy
required to maintain reactor temperature amounts to 200 x 106 to
300 x 106Kcal/year, or up to half the total production when the
reactors are not insulated well. By adding efficient insulation,
this loss can be decreased to about 100 x 10°Kcal per year, or
about 20% of the produced gas. The added insulation, as poly-
urethane, costs about $6000. At a present market value of about
$10 per 106Kcal ($2.50 per 106 BTU) for the gas, the total energy
savings that can be attributed to the insulation would have an
annual value of about $2000. A continuous source of 21°C (70°F)
water could be used to preheat the residue prior to charging the
reactor and also to reduce heat loss from the reactor. Thus,
the savings to be obtained from the heated water from the nuclear
plant would amount to $2000 to $3000 per year.
69
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Estimated Cost of Methane Generation System
A comprehensive study conducted for the U. S. DOE (Jewell et
al^., 1976) estimated the lowest cost that might be involved in
construction of a complete methane generation system for the
size of dairy discussed earlier. This system consisted of
the premix tank, pumps and piping, and reactor (including gas
handling). For these different designs, the range of total
expenditures was $14,,500 to $29,500. These estimates would
appear to be reasonable according to one commercial firm recently
established to build systems at this scale. This firm,
Agricultural Engineering Incorporated, has quoted this type
of system with an internal combustion engine and a 30KW electricity
generator at between $30,000 and $40,000.
The estimated total annual cost of these systems (amortiza-
tion, operation, and maintenance) varies from $3300 to $7650.
These estimates include a minimum amount of insulation, but do
not include the benefits from having the 21°C (70°F) water avail-
able for reducing construction and reactor heating costs. At
the present energy cost of about $10 per lO^Kcal, the annual re-
turn without the 21°C (70°F) water would be about $2400, and
with optimum temperature control the gross value of the energy
would be nearly double this amount. Since natural gas prices
are projected to double in the near future, the energy value
with and without the heated water input would be $6000 and $4800.
As noted earlier, in some instances comparable manure handling
systems that achieve odor control or reduced handling manpower
commitments often cost approximately the same as the above costs.
In these instances, the cost of the energy is greatly reduced.
Heat Recovery Potential
The value of an unlimited supply of heated water at a mini-
mum of 21°C (70°F) could be significant in operating a biologi-
cal fermenter at 35°C(95°F). For a 100-cow milking dairy, the
energy savings could result in enough to make the operation
economically attractive.
There are two general requirements needed to make energy
recovery attractive at the scale discussed here:
1. The cost of energy, especially natural gas, must
continue to increase in value.
2. The demand for the biogas must be constant and
uniform and equal to the production.
The price of natural gas will probably continue to increase in
cost; but, matching the demand with the supply is much more
difficult. In this case, if it is assumed that the gas can be
used to increase the water temperature to a level useful for
greenhouse heating, the requirement for a continuing demand may
70
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be partially satisfied. Biogas can be compressed and stored
for future use or sale.
The energy that could be supplied from the Miller farm
residues of 500 x lO^K cal per year can be translated into the
total quantity of water that could be heated to 29°C (85°F) if
the starting temperature was 21°C (70°F). Assuming that the
transfer efficiency is 100%, the average water flow during a winter
day that could be heated to 29°C (85°F) would be equal to
190 cubic meters (50,000 gallons). The total amount of
energy and its relation to greenhouse heating needs to be
examined.
Recommendations
The recovery of solar energy fixed in presently unused
agricultural residues would appear to be representative of
several technologies that are ready to be examined for large
scale development to assist in development of new, clean,
renewable energy sources. However, the lack of full-scale
applications on common agricultural operations, such as
dairies, is preventing development of costing and feasibility
information needed to make key cost effective decisions. The
development of a system incorporating nuclear cooling water
would assist in demonstrating the feasibility of the operation
as well as to illustrate a useful by-product of nuclear power
generation.
71
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PLANT
21°C (70°F)
Pump 100
gpm
Manure
Power Plant Cooling Water
External Heat Exchanger
Concrete
3.048m (10 ft inside
height 7.62m (25 ft)
diameter maintained
at 35°C (95°F)
Ramp
Pump
at
Farm
Jacketed
premix tank
20m3 (706.7 ft3)
volume
120-
day
Storage
Holding
Pond
38.1m (125 ft) wide
x 38.1m (125 ft)
long x 3.048m (10 ft)
deep
land
Figure 2.
Digester location relative to nuclear plant
premix tank and storage holding pond.
72
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Rainfall
into
Storage
i I
Evapora- f
ft 2 ft Free- tion from \
\ I 1
above
Surface
.board
pill r _ _
\Rainfall-Evaporation-Net Rain /<^mergenny
^7^ Spillwav to
Other Liquid Sources / c£oplanj
Manure
Liquids stored in holding pond
•
Unloading with
horizontal pump
Figure 3. Holding pond and unloading- pump location.
13
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ANNEX TO APPENDIX B
ANAEROBIC FERMENTER DESIGN
FOR A DAIRY FARM OF 200 COWS (TOTAL)
I. Estimation of Agricultural Residues
A. Assumptions
1. Number of cows: 200 total
123 milking
3 bulls
74 replacement
2. Wastes generated
Manure: 84 lb/1000-lb cow/day
Milking: 33.8 Ib/cow/day
Bedding: 1.5 Ib/replacement cow/day
4 Ib/miIking cow/day
Feed: 1.5 Ib/cow/day
3. Combined waste characteristics
Total solids (TS): 12%
Total volatile solids (VS): 85%
4. Waste is removed on a daily basis and the animals
are confined 100% of the time.
5. Average animal weight: 1250 Ib
B. Waste Generation
Daily Waste Generation (Ib, wet basis)
123 Milking 74 Replacement Total
Cows Cows 3 Bulls Ib.
#
Manure 13,161 4,086 178 17,425
Milking Center 4,153 — — 4,153
Bedding 307 110 4 421
Feed Waste — — — 244
Total Daily Waste (12%TS) 22,243
Full Strength
22,243 Ib/day 10 m3/day (352 ft3/day) of 12% TS Waste
Diluted to 10% TS
10 m3/day (352 ft3/day) x 12 = 12 m3/day (422 ft3/day)
10
75
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Concentration
Volume of Waste Generation Per Day
12%
10%
10 m3/day (352 ft3/day)
12 m3/day (422 ft3/day)
II. Fermenter Design
Criteria
Waste flow for 200 cows
Premix tank volume
Pump rate (feeding & recirculation)
Hydraulic retention time
Temperature
Solids loading rate
Tank Volume
Liquid volume
Add about 20% for freeboard
Tank volume
12 m3/day (422 ft3/day)
20 m3
.4 m3/min or 100 gpm
about 10 days
35°C (95°F)
8.3 kg/m3-day
(.5 Ib/ft3-day)
12 m3/day x 10 day HRT =
119 m3
119 + .2 x 119 = 143 m3
(5046 ft3)
Tank Dimensions
A cylindrical tank design, above-ground concrete structure:
Wall thickness
Tank height
Tank diameter
15.24 cm (6 in)
3 m (10 ft)
7.6 m (25 ft)
III. Digester Heating Requirement*
Assume the following conditions apply:
1. Concrete digester surfaced with polyurethane insulation,
above-ground construction, of the following dimensions:
Total depth
Liquid depth
Diameter
Concrete wall & floor thickness
Concrete cover thickness
Insulation thickness on walls
and cover
3.048 m (10 ft)
2.44 m (8 ft)
7.62 m (25 ft)
15.24 cm (6 in)
15.24 cm (6 in)
10.16 cm (4 in)
* Wastewater Engineering, Metcalf and Eddy, Inc., McGraw-Hill Book
Company, New York, N.Y., 1972 Ed.
76
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2. Heat Transfer Coefficients
Slurry - 6" concrete - 4" polyurethane-air ,
U = .15 BTU/hr-ft -°F
Slurry - 6" concrete floor - wet soil,
U = .15 BTU/hr-ft2-°F
Gas - 6" concrete wall or cover - 4" polyurethane-air
U - .05 BTU/hr-ft2-°F
3. Temperatures
Worst Case Average Case
Digester 35°C (95°F) 35°C (95°F)
Air -18°C (0°F) 7°C (45°F)
Earth below floor 0°C (32°F) 7°C (45°F)
Feed from barn 1.6°C (35°F) 7°C (45°F)
4. Areas
Wall in contact with slurry
A = 7.62 m x-rrx 2.44 m = 58.34 nT (628 ft2)
Wall in contact with digester gas
A = 7.62 m xTT x .61 m = 14.6 m2 (157 ft2)
Floor or Cover 7
A =1T (7.62 m) = 45.6 m2 (491 ft2)
Calculations
Heat Losses
Q = A (T2- TX) U
Wall in contact with slurry
Q = 628 x (95-0) x .05 = 2983 BTU/hr, worst case
Q = 628 x (95-45) x .05 = 1570 BTU/hr, average
case
Wall and cover in contact with digester gas
Q = (157 + 491) x (95-0) x .05 = 3078 BTU/hr
worst case
Q = (157 + 491) x (95-45) x .05 = 1620 BTU/hr
average case
Floor
Q = 491 x (95-32) x .15 = 4640 BTU/hr, worst case
Q = 491 x (95-45) x .15 = 3682 BTU/hr, average case
Heating Requirement for the Feed
Without preheating
Worst case Q = 22243 Ib/day x (95-35) °F x
1 BTU/lb-°F = 1.33 x 106 BTU/day
(55600 BTU/hr)
77
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Without Power
Plant Waste
Heat Usage
With Power
Plant Waste
Heat Usage
Average Case Q = 22243 Ib/day x (95-45)°F x
1 BTU/lb-°F = l.ll x 106 BTU/day
(46200 BTU/hr)
After preheating to 18.2°C (65°F) with waste heat
Q = 22243 Ib/day (95-65)°F x 1 BTU/lb-°F =
.67 x 106 BTU/day (28000 BTU/hr)
- SUMMARY OF HEATING REQUIREMENTS -
Heating Requirements (BTU/hr)
Worst Case
Average Case
Worst Case
Average Case
Walls
and cover
6060
3190
6060
3190
Floor
4640
3680
4640
3680
Influent
Heating
55,600
46,200
28,000
28,000
Total
66,330
53,070
38,700
34,870
IV. Digester Gas Yield Estimates
Volatile Solids Destroyed :
Biogas Produced :
Methane Produced* :
Gross Energy Output Rate**:
32% or 330 kg/day (726 Ib/day)
275 m3/day (9682 ft3/day)
165 m3/day (5809 ft3/day)
242,000 BTU/hr
Digester Energy Balance (BTU/hr)
Gross
Pro-
duction
Without Power
Plant Waste Worse Case
Heat Usage Average Case
With Power
Plant Waste
Heat Usage
Worse Case
Average Case
242,000
242,000
242,000
242,000
Digester
Heat
Losses
10,700
6,870
10,700
6,870
Influent
Heat Re-
quirement
55,600
46,200
28,000
28,000
Net BTU/
hr
Output
175,700
188,900
203,300
207,100
*Gross methane production calculated from the estimated volatile
solids destruction: one liter Methane @ STP = 0.5 l/gVSD x g volatil0
solids destroyed.
**The heating value of methane is 995 BTU/ft3
78
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V. Holding Pond
Criteria
4-month holding capacity
Design
Waste flow = 12 m3/day (422 ft3/day) =
1428 m3/120 days (50460 ft3/120 days)
4-month waste generation = 12 m3/day (422 ft3/day) x
120 days = 1428 m3 (50640 ft3)
Average rainfall for Vermont: 45.7 - 121.9 cm/yr
(36 - 48 in/yr)
Overdesign to accommodate precipitation = 50%
Total Pond Volume - 1428 x 1.5 = 2142 m3 (75,960 ft3)
Pond Dimensions:
Length 38.1 m (125 ft)
Width 38.1 m (125 ft)
Depth 2.44 m (8 ft) + .070 m (2ft)
freeboard = 3.05 m (10ft)
3 sides sloped 2:1
1 side sloped 3:1
79
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REFERENCES
Jewell, W. J. , 1976. "Bioconversion of Agricultural
Wastes for Pollution Control and Energy Conservation."
U.S. ERDA report TIO - 27614. Available from the NTIS
system, U.S. Department of Commerce, Springfield, Virginia
22161. 321 pages.
81
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APPENDIX C
WASTE HEAT UTILIZATION
DEMONSTRATION GREENHOUSE
DESIGN CONCEPT
Donald R. Price
Department of Agricultural Engineering
Cornell University
Ithaca, N.Y.
July 1977
83
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CONTENTS
Page
Figures 87
Tables 87
1. Introduction 89
2. Description of Demonstration Complex 89
Greenhouse No. 1: Solar Greenhouse 90
Greenhouse No. 2: Heat Pump 90
Greenhouse No. 3: Rutgers1 Design 90
Greenhouse No. 4: Methane House 91
3. Demonstration Greenhouse Designs 91
Energy Conserving Basic Greenhouse Designs . . 91
4. Potential Greenhouse Crops 106
Vegetables 106
Cropping Patterns 107
Other Crops 109
Background on Commercial Flower Production . . 109
5. Suggested Plantings for Demonstration Greenhouses . 110
(Varieties and Schedule)
Greenhouse No. 1 110
Greenhouse No. 2 110
Greenhouse No. 3 110
Greenhouse No. 4 Ill
6. Cost Estimates for Demonstration Greenhouses. . . . Ill
(Initial Costs)
Greenhouse No. 1 (Solar, Waste Heat) 112
Greenhouse No. 2 (Heat Pump) 112
Greenhouse No. 3 (Rutgers1 Design) 112
Greenhouse No. 4 (Methane) 112
Headhouse for Storage and Handling and Office
Space 113
Greenhouse Operational Equipment 113
7. Cost Estimates (Annual Operating) 113
8. Estimated Production Income (Annual) 114
9. Greenhouse Heating Systems and Heat Loss Calculation
Technique 115
Heating System Efficiencies 115
Unit Heaters vs Central Heating 115
Central Systems 116
Use of Electric Heaters 116
Fuel Prices 117
Estimating Heat Loss 117
Estimating Fuel Costs for Seasonal Operation . 118
85
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FIGURES
Number Page
1 Layout of the Greenhouse Complex 93
2 End Cross Section of Basic Greenhouse 99
3 Plan View of Basic Greenhouse 100
4 Plan View of Solar House 101
5 End Cross Section View of Solar House 101
6 Diagram of solar Collection and Storage 102
7 Heat Pump Plan View 103
8 Plan View of Methane Unit 103
9 Plan of Rutgers' Greenhouse 104
10 End Cross Section of Rutgers1 Greenhouse 104
11 Plastic Vertical Curtain Heat Exchanger 105
12 Porous Concrete Floor Cross Section 105
TABLES
Number Page
1 Approximate Yields 108
2 Heating Systems Efficiencies H5
3 Cost of Common Fuels H7
4 Heating Value of One Unit of Fuel and Energy. . .
87
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WASTE HEAT UTILIZATION
DEMONSTRATION GREENHOUSE
DESIGN CONCEPT
INTRODUCTION
The concepts designed and described in this report are
recommended for developing a demonstration greenhouse complex
to use waste heat from the Vermont Yankee Nuclear Power Corpora-
tion plant near Vernon, Vermont. The greenhouse complex is part
of a total demonstration of waste heat utilization at the site.
A companion aquaculture demonstration unit is located at the
same site.
Because this concept is for demonstration and testing,
four different heating techniques are to be demonstrated. Each
of the four greenhouses will be heated either directly or in-
directly by warm water 21°C (70°F) from the nuclear power plant.
A recommended crop and cropping pattern is given for each
greenhouse. The greenhouse units may be used by universities or
other research groups in the area for experimentation and testing
of plants and production schemes.
After initial testing of the heating systems, one or more
°f the designs may be scaled-up to a large commercial production
unit. Data collected from the demonstration units will be made
Available for analysis and used to project large scale operations.
1ne layout of the demonstration units is illustrated in Figure 1.'
DESCRIPTION OF DEMONSTRATION COMPLEX
The greenhouse heating demonstration complex is divided in-
to four units. Each unit includes a 7.93 m (26 ft) x 18.3 m
(60 ft) greenhouse designed for maximum solar utilization and
Deduced external heat loss. The greenhouse is designed with a
large south facing transparent surface (double layer poly-
^thylene) and an insulated north wall with a high light reflec-
tive internal surface. This design provides for increased light
Bevels inside the greenhouse when compared with conventional
greenhouse designs. The heat loss is reduced by approximately
b°% over conventional designs. (See Figure 1)
Each of the four greenhouses is heated either directly
ith the warm water from the power plant or indirectly utilizing
ne warm water to assist a heat pump and to produce methane gas
rom an anaerobic digester located on a nearby dairy farm.
89
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Greenhouse No. 1; Solar Greenhouse
This greenhouse is equipped to store excess solar
energy collected by the greenhouse in gravel storage benches
located inside the greenhouse. The heat is recovered from
the gravel storage for nighttime heating. In addition to
the solar collection and storage, a commercial water to air
heat exchanger is utilized. A backup 9.5 kw electric
resistance heater is included in the design.
No external solar collectors are utilized as the green-
house itself acts as the collector. The gravel storage units
inside the greenhouse double as the growing benches. An air
handling unit was designed to collect excess heat and deliver
it to the gravel storage.
Greenhouse No. 2; Heat Pump
The same basic greenhouse design is utilized without the
solar storage units. In this house, a water to air heat pump
is utilized with a constant source of 21°C (70°F) water supplied
by the power plant. The operating coefficient of performance
(COP) for the water to air heat pump is approximately 3 compared
to 1.75-2.0 for air to air units now commonly used.
In addition to the heat pump, one water to air heat ex-
changer (commercial unit) will be utilized for base load heat-
ing. The heat pump will be utilized as an assist during the
coldest operating periods. There is no other backup heating
provided for this house, as the heat pump is designed to meet
the greenhouse design temperature requirements at the outdoor
design temperature of -26°C (-15°F).
Greenhouse No. 3; Rutgers' Design
This design is likely to be the most controversial and may
be omitted if regulations prohibit the direct use of the
warm water from the cooling system of a nuclear plant.
In this house, the floor is constructed of porous concrete
and warmed water flows through a gravel bed beneath the
floor.
Low temperature, low cost heat exchangers are designed to
utilize the warm water directly. Porous pipes are draped with
polyethylene sheets the full length of the house in five separate
rows. Water flows from the porous pipe down between the plastic
sheets and through the porous concrete floor.
The pipes draped with plastic may be raised at night for
maximum heat exchange and lowered during the day when less heat
90
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is required and more light is required at the plant level.
In this house, one commercial water to air heat exchanger
is utilized to assist the plastic heat exchangers. The two ex-
changers are designed to maintain a minimum of 10°C (50°F) in
the greenhouse on the coldest nights. Because of the lower
temperature conditions, it is suggested that this house be
utilized for cooler temperature potted plants.
Greenhouse No. 4; Methane House
This house is unique in that the total heating is
provided by methane gas produced on a nearby dairy farm. The
manure from about 200 dairy cows is converted to methane gas
in an anaerobic digester located on the farm. The gas is
piped to the greenhouse by an underground pipeline.
Gas unit heaters (2) are utilized to provide the total
heating of the greenhouse. Sufficient gas will be produced to
maintain maximum air temperatures of 18°-21°C (65°-70°F) on a
continuous basis. Because of the capability of maintaining the
higher temperatures, either roses or cucumbers are suggested as
ideal crops for this house.
The warm water from the power plant is utilized indirectly
in this instance. The anaerobic digester must be maintained at
32°-35°C (90°-95°F) for maximum gas production. The 21°C(70°F)
water from the power plant assists in maintaining the higher
temperature in the digester, and more gas is available for out-
side uses. Without the assistance of the warm power plant water,
nearly one-half of the methane gas produced would be required to
maintain the 32°-35°C (90°-95°F) in the digester. With the warm
water, only 20% of the gas produced will be required by the
digester.
In addition to the greenhouses, a head house is required
and also space for scientists to collect data from the demon-
stration units and for visitors to observe the facilities.
DEMONSTRATION GREENHOUSE DESIGNS
Energy Conserving Basic Greenhouse Design
Greenhouses have historically not been designed with energy
conservation in mind. The design suggested here incorporates a
shape and construction materials to maximize the collection of
solar energy while reducing the heat losses from the structure.
A descriptive sketch for the greenhouse structure is included
with this report. The heating systems to utilize the warmed
water discharge from the power plant condenser are all utilized
91
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within the basic greenhouse design.
For comparison, the heat loss from a conventional green-
house at the outside design temperature of -26°C (-15°F) and
inside design temperature of 18°C (65°F) is calculated to be
about 240,000 BTU/hr. The heat loss from the energy conserving
design is calculated to be about 100,000 BTU/hr under the same
design conditions or about 60% less than the conventional house.
The key to utilization of low temperature heat, such as the
power plant discharge or solar energy, is to reduce the heat
losses to a reasonable level.
Four different experimental greenhouse heating system de-
signs are suggested for the Vernon plant. Each greenhouse will
be the basic nominal 7.93 m (26 ft) x 18.3 m (60 ft) size and
incorporate the proper shape and orientation for maximum solar
utilization and minimum heat loss from the structure. The
standard greenhouse design is illustrated in Figures 2 and 3.
Each greenhouse, except the methane-heated unit, will be partially
heated with the 21°C (70°F) discharge water from the power plant
condenser discharge. The greenhouse units will utilize water to
air heat exchanger units similar to the Trane centrifugal air
handler with finned-tube heat exchanger units as used in the
Northern States Power demonstration unit.* The units may be
purchased from the manufacturer with the specifications provided
in the design criteria.
The four greenhouses will incorporate different heating
techniques. Greenhouse No. 1 will be equipped to collect, store,
and use when needed excess solar energy to partially offset the
heating requirements. The design for greenhouse No. 1 is illus-
strated in Figures 4, 5, and 6. Greenhouse No. 2 will include the
use of a warm water-assisted heat pump to provide for a COP of
approximately 3. The heat pump will be assisted by one water
to air finned-tube heat exchanger. The design for greenhouse
No. 2 is illustrated in Figure 7. Greenhouse No. 3 will be re-
ferred to as the Rutgers1 design and incorporates the technique
of underfloor supply of warm water at 21°C (70°F) from the power
plant using a porous concrete floor. Low cost, low temperature
heat exchangers are designed for additional heating using the
condenser water. The greenhouse No. 3 design is illustrated in
Figures 9, 10, 11 and 12. The final greenhouse design,
greenhouse No. 4 will be partially heated using methane gas generated
from an anaerobic digester located on a nearby dairy farm.
Greenhouse No. 4 design is illustrated in Figure 8.
*Ashley, G. C. and J. S. Hietala. A Sherco Greenhouse: A
Demonstration of the Beneficial Use of Waste Heat. Proceedings of
the Conference on Waste Heat Management and Utilization, May 9-11, 1977,
Miami Beach, Florida.
92
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The greenhouses may be arranged as desired on the Vernon
plant property. A suggested layout is given in Figure 1. The
warm water supply may be taken directly from the discharge canal
for use in greenhouse heating. The exception to this may be the
Rutgers1 design. If the use of the warmed water directly is
prohibited by federal or state regulations, the Rutgers' design
may either be eliminated or water supplied from a heat exchanger
similar to the one designed to supply warmed water for the aqua-
culture unit.
A. Heat Loss Estimates for the Basic Greenhouse Design
Design Criteria:
1. 7.93 m (26 ft) x 18.3 m (60 ft)
2. East-west orientation
3. Climatic conditions for southern Vermont
a) winter design temperature = -26°C {-15°F)
b) greenhouse inside temperature = 10°C (50°F)
night
= 18°C (65°F)
day
4. Percent possible sunshine during winter = 40%
5. Insulated north wall "R"* = 16 R units
6. South slope elevation =38° from horizontal
Heat Loss Estimates:
Floor 9,153 BTU/hr
Thermal Radiation Exchange 30,164 BTU/hr
Cover Loss: Transparent surface +
Insulated surface 66,992 BTU/hr
Infiltration Loss 15,173 BTU/hr
(2 air changes/hour)
TOTAL 121,484 BTU/hr
If the inside temperature is maintained at 18°C (65°F), the
total heat loss estimate is 152,513 BTU/hr. The use of a black
cloth curtain drawn over the transparent surfaces has been shown
to reduce nighttime heat loss by up to 50%. Using a more con-
servative factor of 25% reduction, the nighttime heat loss
estimate is 91,086 BTU/hr at 10°C (50°F) minimum and 114,384
BTU/hr at 18°C (65°F) minimum interior greenhouse temperature.
B. Solar Greenhouse Design Specifications (Greenhouse No. 1);
Design Criteria:
1. Latitude 43.6°
2. Clear Sky
a) insulated surface absorptivity = 0.9
b) non-insulated surface absorptivity = 0.21
*Thermal Resistance("R")- The ability of a material or combination
of materials to retard or resist the flow of heat.
93
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Total Daily Solar Gain on a Clear Day:
1. Transparent south surface = 1,614,69.3 Biu
433 BTU
.
2. Transparent east and west surface =
3. North insulated surface = *™
4. South facing insulated surface = 46,676
TOTAL DAILY SOLAR GAIN 1,811,224 BTU
Heat Storage: . .
1. Sixty tons of crushed rock may be stored in tne
2. Assuming 10 °C (50°F) of useful collection and 38°C
(100°F) maximum rock temperature, the amount of
heat that can be put in the rocks is 1,200,000 BTU,
3 The nighttime heat requirements to maintain the
greenhouse at 10°C (50°F) using the black cloth
system was 91,086 BTU/hr.
4. Therefore, reclaiming the stored heat from the
rock storage would provide approximately 14 hours
of heating.
5 It is evident from the calculation of total solar
gain on a clear day that on a typical winter day
1,200,000 BTU of solar energy will not be avail-
able for storage. The gravel storage may provide
heat for 3 to 4 hours of nighttime heating during
the design winter period; however, during the
spring and fall periods up to 100% of the heating
may be offset from the solar collection and
storage of excess heat.
Water-to-air Heat Exchangers:
The commercial finned-tube heat exchanger with centri-
fugal air flow delivery will provide 82,000 BTU/hr if the
entering water temperature is 21°C (70°F) and the entering
air has a temperature of 10'C (50«F) . The water flow rate
should be 29 gallons per minute (0.0018 m /s) and the
air flow rate should be 7000 cfm (3.3 mj/s) .
If the water temperature is 24°C (75°F) with all other
parameters the same, the heat exchanger could provide
103,000 BTU/hr.
The suggested exchanger units are available from the
Trane Company.
Specifications: Fan (L-12, 7000 cfm)
Coil (Series 16 with 3 rows
of tubes)
Motor (3 HP)
Filter and mixing (M-90)
94
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Therefore, given the nighttime maximum heat loss
rate of 91,086 BTU/hr to maintain a 10°C (50°F) minimum
temperature in the greenhouse, the solar heating with
storage and the use of two finned-tube water to air
heat exchanger units should ensure the necessary heating
requirements. Maintaining 18°C (65°F) in the greenhouse
would also be possible; however, long periods of cloudy
weather would place the heating at the very limits of the
design.
C. Heat Pump Heated Greenhouse (Greenhouse No. 2);
The heat pump will operate at a constant COP of approxi-
mately 3, and therefore a commercial heat pump may be selected
to supply 160,000 BTU/hr to maintain the greenhouse at a 18°C
(65°F) minimum temperature. Carrier Model 2400, or an equivalent
heat pump from Westinghouse or General Electric, will be satis-
factory.
If the water to air heat exchanger is included in the
greenhouse design, the heat pump capacity could be reduced by
about 1/2. One heat exchanger unit is recommended to help offset
heating cost.
Warm water supplied to the heat pump at 21°C (70°F) would
increase the overall winter heating COP from about 1.75 to
approximately 3. The electric energy required to heat the green-
house with such a heat pump is obviously 1/3 that of direct re-
sistance heating and a little less than 2/3 that without the
21°C (70°F) source of water. This heat pump would allow higher
operating temperatures in this house for cucumber production.
Annual estimated electrical use for heat pump:
Criteria:
18°C (65°F) (minimum temperature)
114,384 BTU/hr (max. heat loss)
7800 (degree days)
0°C (32°F) (average winter temp.)
21°C (70°F) (average inside temp.)
Annual total electricity required for heating with water-
to-air heat pump is:
21,308 Kwhr @ 4C/Kwhr = $852.00
Direct resistance electric heating would result in
63,925 Kwhr total, and at 4C/Kwhr the annual cost would be
$2,557.00. Therefore, just the annual electrical energy
savings by use of the heat pump over direct resistance heating
is about $1700.00.
The air to air heat pump would require about 36,500 Kwhr
annually at a cost of about $1461.00. Therefore, the value of
95
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the warm water from the power plant for greenhouse heating for
the 7.93 m (26 ft) x 18.3 m (60 ft) demonstration greenhouse is
$609.00 annually.
As a further comparison, the annual cost for heating the
greenhouse with 12 fuel oil is estimated to be $1239 if #2 fuel
oil costs 50£/gal. Therefore, the warm water assisted heat pump
would save approximately $4000 per year when compared to the use
of fuel oil for heating in the No. 2 greenhouse.
The above comparison is given for the situation where all
the heating is done by the heat pump. In greenhouse No. 2, the
heat pump cost is also offset by the use of the water to air
heat exchanger. The estimated total electric cost when using
both units is $420 annually.
D. Rutgers' Greenhouse Design (Greenhouse No. 3);
The exchanger consists of a single sheet of plastic film
draped over a supporting member and hanging down to the floor
on each side (see Figure 11). A trickle irrigation device, twin
wall hose, is attached to the supporting member under the film.
Warm water supplied by the power plant condenser discharge is
pumped from the floor storage into the twin wall hose and flows
by gravity between and down inside surfaces of the plastic sheet
onto the floor. Since the floor is constructed of porous con-
crete, no collecting device is needed, and the water returns to
the storage area directly under the floor. Tests conducted by
Rutgers on this exchanger design indicate an overall heat trans-
fer coefficient of 0.95 BTU/hr-ft2-°F when there is a 14°C (25°F)
temperature difference between the average heat exchanger
temperature and inside greenhouse air ambient. The plastic ex-
changers can be elevated or dropped during the day to avoid
shading the crops. Low pump horsepower and energy are required
because the storage is just below the floor and the twin wall hose
operates at low pressure. Evaporation is limited because the
water runs between the layers of film.
Criteria:
1. 5 heat exchanger polyethylene curtains
2. Curtains elevated to 1.22 m (4 ft) maximum
3. Total curtain area = 223 m2 (2400 ft2)
4. 1/2 floor area (available for heat exchange)
5. Condenser water at 21°C (70°F) (available in con-
tinuous supply)
6. Total water flow = 60 gpm (0.0038 m3/s)
7. Temperature difference between curtain wall and
greenhouse air~ delta-T 20°F
Heating supplied by curtain exchanger and floor:
Using the heat transfer coefficient of 1.53 as suggested
by Rutgers1 design:
Total heat transfer = 73,000 BTU/hr
96
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The Rutgers1 design alone will not be adequate to pro-
vide a minimum 10°C (50°F) nighttime greenhouse air temperature.
Condenser water at 24 °C (75°F) would provide this minimum tem-
perature. The addition of one water to air heat exchanger unit
will satisfy the heating requirement for the Rutgers' design
and a minimum 10°C (50°F). (See Figures 9, 10, 11 and 12.)
E. Methane-Heated Greenhouse (Greenhouse No. 4);
Criteria:
1. Actual digester design data were supplied by
Dr. W. J. Jewell*.
2. Estimated daily production for winter conditions
for the 200-cow dairy is approximately 200,000
BTU/hr.
Design Requirements:
If 200,000 BTU/hr (methane equivalent) were available
on a continuous basis from the dairy farm, the methane-
heated greenhouse could be maintained at 18°C (65°F) or
higher on a continuous basis with some additional gas a-
vailable for water heating or other uses at the dairy farm.
The greenhouse should be designed for two, gas-fired,
unit heaters to deliver 100,000 BTU/hr each. (See Figure 8.)
F. Summer Cooling (Ventilation):
Criteria:
Summer design temperature
Dry bulb temperature = 32°C (90°F)
Wet bulb temperature = 23°C (73°F)
With these outdoor design conditions and using one
air exchange per minute, the inside temperature will rise
a maximum delta-t of 4.5°-5.5°C (8°-10°F) over the out-
side temperature. The inside temperature could reach
as high as 43°C .(110°F) on the hottest summer days.
The recommended fan capacity for one air exchange per
minute for the basic greenhouse design is 374 m3/min
(13,200 ft3/min)
G. Maximum total water flow from the power plant to the demon-
stration complex is 200 gpm (0.0126 m3/s).
*See Appendix B
CC7
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V0
00
SYMBOLS:
HE
HP
GH
POWER PLANT
HEATED WATER
SUPPtf
GREENHOUSE WASTE HEAT UTILIZATION
COMPLEX DEMONSTRATION UNITS
DISCHARGE
TO RIVER,
tfi PLASTIC EXCHANGERS®
?*f: ....„_ ..—..— ?v"•i.-'-cXx'f'T-*-
WATER TO AIR HEAT EXCHANGER
WATER TO AIR HEAT PUMP
UNIT GAS HEATER
WARM WATER SUPPLY
DISCHARGE BACK TO RIVER
METHANE GAS SUPPLY
METHANE FROM
DAIRY FARM
FIG. I, LAYOUT OF THE GREENHOUSE COMPLEX
-------
NORTH-
1/2 PLYWOOD
ROOFING
4x4 PPT.
CONC. COLLAR
GREENHOUSE SECTION
FIG. 2. END CROSSECTION OF BASIC GREENHOUSE
99
-------
O
o
m
CO
14
RIDGE LINE
T>
o
60'- 0"
FIG. 3. PLAN VIEW OF BASIC GREENHOUSE
-------
60- 0"
WATER-
AIR
HEAT EXCHANGER
SOLAR COLLECTOR
ROCK STORAGE UNITS ..
CM
PLAN
FIG. 4. PLAN VIEW OF SOLAR HOUSE
WATER-AIR
HEAT EXCHANGER
CURTAIN
ROCK
STORAGE
UNITS
SECTION
SOLAR ASSISTED WITH WATER TO AIR
HEAT EXCHANGER SYSTEM
FIG.5. END CROSSECTION VIEW OF SOLAR HOUSE
101
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COLLECTION- DISTRIBUTION MODES
CENTRIFUGAL
COLLECTION
FAN-
TAPERED DUCT
5/8" SLOT
AIR DISTRIBUTION
MANIFOLD
5 AIR TRAVEL
'SPACE (PLENUM)
v^->'^;vv'^^^:.^-^-^:^--^^:^
£^;&£^%^
^^^•-.^-.^^^.---.^.^..-.y .,pV,^V V.^V^
I 1/2" STEEL MESH OUTLET SLOTS
4r
EXHAUST FAN
-AUXILIARY DUCT HEATER
\ \ \ \ \
FIG. 6. DIAGRAM OF SOLAR COLLECTION AND
STORAGE
102
-------
60-0'
HEAT PUMP
WATER TO AIR
HEAT EXCHANGER
.1 t .. t t t
r i i
•
(O
WATER TO AIR HEAT PUMP SYSTEM
FIG.7. HEAT PUMP PLAN VIEW
60'-0
_
GAS HEATER
J-, \ \ \
1 • 1 1
jliiliis | i i
1 1 1
t
1
GAS HEATER
I X
1
i:tt:W:;:;:;
"o
1
CM
METHANE GAS HEATING SYSTEM
FIG. 8. PLAN VIEW OF METHANE UNIT
103
-------
WATER
AIR
HEAT 1
1
IB
_
EXCHANGER
I
^A
^ VINYL CURTAINS
O
i
~
-------
SUPPORT
CABLE-
WATER
DISTRIBUTION
PIPE
WATER v-A
FLOW 3$
DIRECTION
PLASTIC SHEET DRAPED OVER
WATER DISTRIBUTION PIPE
FIG.II. PLASTIC VERTICAL CURTAIN HEAT
EXCHANGER
3 POROUS
CONCRETE-
S'1 OF 5/8"01A.
BLUESTONE
2"STYROFOAM.
.
'
e^^S%^^^^
EARTH
VINYL LINER
10 MIL
POLYETHYLENE
WATER BARRIER
FIG. 12. POROUS CONCRETE FLOOR CROSS SECTION
105
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POTENTIAL GREENHOUSE CROPS
Vegetables
Tomatoes, lettuce and cucumbers are the most typical green-
house vegetable crops. Because of high heating requirements and
low light intensities during the midwinter months, very little
vegetable greenhouse production exists in the Northeast. Vege-
tables are grown in the Southern and Western United States and
shipped to the Northeast.
Increased transportation costs may gradually cause a shift
back to greenhouse vegetable production in the Northeast. New
Jersey still has a sizable tomato greenhouse production.
Tomatoes have historically been a high yielding, high value
crop. In a well-managed greenhouse, the potential yield of
tomatoes is 73-95 megagrams (80-105 tons) per acre per year
(two crops). While higher yields have been reported, they are
rare and cannot be counted on. A figure of about 82 megagrams
(90 tons) per year per acre would seem average. Yields of
the spring crop may be almost twice that of the fall crop.
The optimum air temperature range for growing of tomatoes is
near 21°C (70°F). (Optimum temperature of crops is important, not
only because it indicates the best growing range, but also be-
cause it can save money for the operator if seasonal changes of
temperature are accounted for.) The wholesale price for tomatoes
varies from 45
-------
get about 5 crops for a maximum of 234,389 kg (518,000 Ib)
of cucumbers per acre.
Other vegetables, such as radishes [optimum temperature
15.5°-21°C (60°-70°F)j could also be grown. Their value on the
market is much less, and thus radishes are not normally included
in production schemes.
Cropping Patterns
Using the crop information and incorporating growing time,
temperature, planting procedures, etc., several crop patterns
are possible. All of the following can be found in greenhouses
in the Northeast although some may be on a very small scale.
Plan
1
2
3
4
5
6
7
8
9
10
Fall Early (Winter)
Tomato
Tomato
Tomato
Lettuce
Lettuce
Lettuce
Lettuce
Tomato
Cucumber Crop Year
Tomato
Mid-Winter
Lettuce
Lettuce
Lettuce
Lettuce
Lettuce
Around (more
Lettuce
Spring
Tomato
Cucumber
Cucumber
Tomato
Tomato
Cucumber
Lettuce
Tomato
than 5 crops)
Tomato
Summer
Seedless
Cucumber
Plan #1: a) Tomatoes: Seed sown Oct. 25 to Nov. 10. Plants set
in houses about Jan. 10, vines removed
July 1 to Aug. 1.
b) Tomatoes: seed sown June 15 to July 1. Plants
set in houses Aug. 1-15, vines removed
Dec. 15 to Jan. 1.
Plan #2: Similar to #1
Plan #3: a) Tomatoes: seed sown July 1-15. Plants set in
houses Aug. 15-30, vines removed
Dec. 15-31.
b) Lettuce: seed sown Nov. 15-30. Plants set in
houses Dec. 15-31. Crop harvested
March 15-31.
x) Cucumbers: seed sown Feb. 1-15. Plants set in
houses April 1-15, vines removed
July 1-15.
Plan #4: a) Lettuce: anytime early fall or mid-winter.
b) Tomatoes
107
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Plan #5: a)
Lettuce: one early fall planting, seed sown
Aug. to Sept., transplanted in late
Sept., harvested late Oct. and early
Nov.
b) Second crop seeded late Oct., transplanted in
mid-Nov., harvested in Feb.
Plan #6: Similar to #5.
Plan #7: Same as #5, only continue with lettuce.
Plan #8: Same as #3, except substitute tomatoes for late
spring crop, and grow seedless cucumbers in
summer months.
Plan#9: Self-explanatory.
Plan #10: Derived from Plan #8.
Table 1. Approximate Yields
Plan
1
2
8
9
10
Tomato-Tomato
Tomato
Cucumber
Tomato
Lettuce
Cucumber
Lettuce
Tomato
Lettuce
Lettuce
Tomato
Lettuce
Lettuce
Cucumber
Lettuce
Lettuce
Lettuce
Tomato
Lettuce
Tomato
Cucumber
Cucumber (all year)
Tomato
Lettuce
Tomato
Yield
90 tons/acre*
30 tons/acre
8600 doz/acre
30 tons/acre*
43,560 lb/acre
8600 doz/acre
43,560 lb/acre
60 tons/acre
2 x 43,560 lb/acre
60 tons/acre
2 x 43,560 lb/acre
8600 doz/acre
3 x 43,560 lb/acre
30 tons/acre
43,560 lb/acre
60 tons/acre
8600 doz/acre
518,000 lb/acre
30 tons/acre
43,560 lb/acre
60 tons/acre
* It was assumed spring tomato production to be approximately two
times that in the fall. 1.0 kg = .0011 short U.S. ton or 2.205
108
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Other Crops
The more common and more profitable use of greenhouses in
the Northeast in recent years has been for floriculture pro-
duction. Greenhouse temperatures in the range of 13°-15.5°C
(55°-60°F) are acceptable for growing roses, tree seedlings,
snapdragons, and many varieties of potted plants. Roses grow
best in a temperature above 18°C (65°F) but will tolerate
periods of temperatures below 10°C (50°F).
Under the present market structure, the profit from the
production of flowers will generally be greater than vegetable
production and involves less fluctuation in market price.
Background on Commercial Flower Production
Managers of greenhouse floriculture firms generally pro-
duce crops from propagation material (plant cuttings, bulbs,
started plants, seeds) provided by a relatively small number
of national propagation firms. These firms have elaborate
propagation, production and distribution operations which enable
them to provide growers with disease-free, pest-free propagation
material of high quality at the precise time the grower requires
it for his production program.
A commercial greenhouse flower grower manages production
to ensure maximum use of greenhouse production area each week
of the year. In order to effectively serve his markets, a
grower of cut flowers develops tightly scheduled crop rotations
which enable him to place a specified amount of cut flowers in
the market each week. He supplements this production with ad-
ditional units of crops for major holiday and special occasion
markets, e.g., Easter, Christmas, peak wedding months, etc.
Roses, orchids and carnations, all major cut flower corps,
are produced on 4-year, 3-6 year and 1-2 year rotations, respec-
tively. A rose grower orders planting stock to be grown for his
purposes often a year or more before it is required for benching.
The cost of plants and of the labor and other activity involved
in planting represents a significant cost input. Most growers
capitalize their rose plants and depreciate the investment over
the 4-year production period. Orchids represent an even greater
investment per plant with 3-6 year rotations being common.
Carnation crops are managed in a similar way but generally only
over a 1-2 year period. Loss of these crops as a result of in-
terruption of heat would result in loss of a substantial portion
of a multi-year investment.
Chrysanthemums, snapdragons, asters, bulb crops and most
other cut flower crops are produced on 3-4 month rotations
planned to provide weekly marketings on a year-round basis.
While there is considerably less investment in planting stock
for these crops than for roses, orchids and carnations, there is
109
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nonetheless a considerable financial investment. Producers of
potted crops and garden bedding plants are similarly dependent
upon national suppliers for the seeds, cuttings, bulbs and stock
plants with which crops are initiated. Potted crops grown in-
clude poinsettias, Easter lilies, tulips, daffodils, hyacinths,
azaleas, chrysanthemums, hydrangeas and geraniums.
In the case of some greenhouse crops and especially geran-
iums, poinsettias, and foliage plants, stock plants are grown
by producers for the purpose of providing propagation material
from which to initiate final crops for market. For example,
potted geraniums produced for spring sales are often propagated
from cuttings taken from large stock plants started the previous
summer and grown through the fall, winter and early spring.
Growers essentially store cuttings of the large stock plants so
as to have considerable amounts of cuttings available from which
to start the major finished crops. A heating interruption that
resulted in the loss of these stock plants would essentially
eliminate the opportunity for the grower as well as the other
growers whom he supplies to have a source of propagation
material for these crops.
SUGGESTED PLANTINGS FOR DEMONSTRATION GREENHOUSES
(Varieties and Schedule)
A. Greenhouse No. 1
1. Set plants Aug. 1-15 - Tomato (Vendor or Michiana 140)
2. Remove vines Dec. 15-31
3. Set plants Dec. 15-31 - Lettuce (Bibbs)
4. Harvest March 15-31
6. Set plants April 1-15 - Tomato (Vendor or Michiana 140)
8. Vines removed July 1-15
B. Greenhouse No. 2
Cucumber crop year around
5 crops total (English Seedless)
C. Greenhouse No. 3
Potted plants, cut flowers
Variety of species planted to meet special holidays
Chrysanthemums (new variety - cool temperature)
Snapdragons (grow well at low temperature)
Asters
Poinsettias
Easter lilies
Geraniums
Hydrangeas
Best bet: Snapdragons [can grow at 10°-13°C (50°-55°F)1
One bench of chrysanthemums of the new variety
that grow well at low temperatures (ask plant
salesman for new variety)
110
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D. Greenhouse No. 4
The color and variety of roses grown depends on the
needs of the sales outlets in the area. The following may
be grown:
1. Red (most standard color)
a) Forever Yours (most common variety)
b) American Beauty (second most common)
c) Samanathe (new variety - very good so far)
2. White - White Butterfly (most common)
3. Yellow
a) Golden Fantasy
b) Golden Wave
4. Pink
a) Sonia (grows well)
Sweetheart varieties suggested are: 1. Red (Mary Devor)
2. Pink (Bridal Pink
or Carol Amling)
3. Yellow (Golden Garnett)
Suggested best combination:
2/3 of house - Red (Forever Yours)
1/3 of house - Pink Sweetheart (Bridal Pink)
A period of 6-8 weeks elapses between cuttings from same
stem so a limited number of varieties can be effectively
grown in one 7.93 m (26 ft) x 18.3 m (60 ft) house.
DEMONSTRATION GREENHOUSES
COST ESTIMATES*
(Initial Costs)
The cost of materials and labor for construction of the
basic greenhouse is broken down as follows:
1. Materials: 7.93 m (26 ft) x 18.3 m (60 ft) $2475.00
unit
2. Erection (labor) 1050.00
3. Ventilation Fan (13,000 cfm) 425.00
4. Basic wiring, lighting, etc. 275.00
5. Black cloth for night heat retention 175.00
6. Miscellaneous 125.00
TOTAL $4525.00
The individual demonstration greenhouse costs are estimated
as follows:
* All costs are based on 1977 dollars
111
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A. Greenhouse No. 1 (Solar, waste heat)
1. Basic greenhouse $ 4,525.00
2. Rock storage units 61 m (200 ft) 600.00
3. Rocks (No. 3 crusher run) 325.00
4. Air handling duct 275.00
5. Collection fan 225.00
6. Discharge fan 225.00
7. Controls 175.00
8. Centrifugal water to air heat
exchangers (2) (Trane Co.) 3,200.00
9. Pipe and plumbing for Trane units 625.00
10. Miscellaneous 500.00
TOTAL $10,675.00
B. Greenhouse No. 2 (Heat Pump)
1. Basic greenhouse unit $ 4,525.00
2. Heat pump (Carrier Model 2400 or
equivalent) 200,000 BTU/hr rating 3,750.00
3. Plumbing and controls for heat pump
(including wiring) 375.00
4. Polytube air distribution 65.00
5. Centrifugal water to air heat exchanger
(Trane Co.) 1,600.00
6. Plumbing and controls for Trane unit 350.00
7. Miscellaneous 500.00
TOTAL 511,165.00
C. Greenhouse No. 3 (Rutgers1 Design)
T~. Basic greenhouse unit $ 4,525.00
2. Porous concrete floor 1,500.00
3. Vinyl liner 550.00
4. Polyethylene curtain heat exchangers (5) 850.00
5. Centrifugal water to air heat
exchanger (Trane Co.) 1,600.00
6. Plumbing and drains for under floor
water reservoir 850.00
7. Plumbing and controls for Trane unit 350.00
8. Miscellaneous 500.00
TOTAL $10,725.00
D. Greenhouse No. 4 (Methane)
nBasic greenhouse unit $ 4,525.00
2. Unit gas heaters (2)
(100,000 BTU/hr each) 1,650.00
3. Wiring and controls 325.00
4. Plumbing for gas supply at green-
house only 225.00
5. Polytube air distribution 130.00
6. Miscellaneous 500.00
TOTAL 5 7,355.00
112
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E. Headhouse for storage and handling and office space
(Rough estimate) $18,000.00
F. Greenhouse Operational Equipment
1. Tools 600.00
2. Watering systems 1,200.00
3. Soil 550.00
4. Miscellaneous 1,000.00
$ 3,350.00
Greenhouse No. 1 $10,675.00
Greenhouse No. 2 11,165.00
Greenhouse No. 3 10,725.00
Greenhouse No. 4 7,355.00
Headhouse 18,000.00
Operational equipment 3,350.00
TOTAL INITIAL INVESTMENT $61,270.00
COST ESTIMATES
(Annual Operating)
A. Labor
1. Horticulturist
Salary and Fringe Benefits $ 9,600.00
2. Part-time maintenance 4,600.00
3. Part-time workers 2,000.00
TOTAL $16,200.00
B. Fertilizers, pesticides 375.00
C. Vehicle (depreciation & operating) 1,800.00
D. Electricity 1,250.00
E. Plants, seeds, etc. 250.00
F. Miscellaneous 500.00
TOTAL $20,375.00
113
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ESTIMATED PRODUCTION INCOME
(Annual)
Greenhouse No. 1
a) Tomatoes (full crop)
61b/plant, 390 plants/house @ 50
-------
GREENHOUSE HEATING SYSTEMS AND
HEAT LOSS CALCULATION TECHNIQUE
Heating System Efficiencies
The following is a list of efficiencies for various systems,
as given by the American Society of Heating, Refrigerating, and
Air Conditioning Engineers Guide (the ASHRAE Guide).
Table 2. Heating System Efficiencies
Type of Unit
Gas (designed unit)
Gas (conversion unit)
Oil (designed unit)
Oil (conversion unit)
Bituminous coal (hand fired, with controls)
Bituminous coal (hand fired, without controls)
Bituminous coal (stoker fired)
Anthracite coal (hand fired, with controls)
Anthracite coal (stoker fired)
Coke (hand fired, with controls)
Coke (hand fired, without controls)
Electric
Efficiency
70-80%
60-80%
65-80%
60-80%
50-65%
40-60%
50-70%
50-65%
60-80%
60-80%
50-65%
90-99%
These figures are for efficiency of utilization, not furnace
(or conversion fuel) efficiency. These figures reflect the heat
actually delivered to the structure after accounting for such
things as heating effects from the chimney, flue losses, etc.
It can be seen that due to the large number of overlap-
ping ranges, and from the vast number of alternatives known to
exist within each general area, that efficiency alone is not the
sole basis for selecting a system.
Here a system will be chosen by accounting for the capital
cost and then calculating operating costs based on efficiencies,
fuel choice, etc; however, this will be done for specific cases,
with specific problems and eguipment in mind.
Unit Heaters vs. Central Heating
It is generally agreed that for small greenhouses [under
1858 m2 (20,000 ft2)] hot air unit heaters are the most eco-
nomical to operate. The biggest problem with hot air heaters
is delivering the heated air uniformly over an area without
causing undue drafts. Polytubing and various venting systems
have largely taken care of this problem.
For heating larger areas, (on the order of more than an
acre under glass) unit heaters cost about the same as using a
central system. Thus, even large-scale operations are often
115
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heated with unit heaters. However, operating one large central
system requires less continual maintenance than does a system
of unit heaters. Since costs may still be similar, the choice
of heating system is more a matter of individual preference for
each greenhouse operator.
There are advantages to starting with glass if the capital
is available. This is because: (1) the plastic will probably
have to be replaced every year at a cost of about 21£/ft2; (2)
the plastic houses cannot be depreciated as glass houses can
because they are often not considered "permanent" structures;
and (3) plastic, in general, will not transmit light as well as
glass and may have more condensation problems. (Plastic houses
may, on the other hand, have lower heating costs as their over-
all heat loss coefficient is lower: 0.8 BTU/ft2hr°F as com-
pared to 1-1.2 BTU/ft2hr°F for glass.)
Central Systems
If a central system is to be installed, there are many
options open as to: (1) hot water vs. steam heating; (2) piping
arrangements; (3) pumping arrangements, etc.
It is generally thought that for small greenhouses, the hot
water systems are the most practical. When the size exceeds
1400-1858 m2 (15,000-20,000 ft2) of glass, it is probably better
to use a steam system.
Hot water will require larger heating pipes than steam.
Due to resistance effects, box coil piping is best for hot water,
while trombone (continuous) coils are best for steam. (The
normal steam setup is 2/3 side coils and 1/3 overhead coils
evenly distributed. Note that steam systems can sometimes be
utilized for providing soil sterilization, giving this added
benefit. There is an increasing use of finned piping for both
cases (since one length of finned piping may be equivalent to
using four or more plain pipe lengths).
Modern hot water systems under pressure can allow water
temperatures close to that of steam but at a higher capital
cost than the normal hot water system. This will allow its
acceptance for larger heating ranges. In either hot water or
steam systems, those operating on a gravity flow basis are no
longer considered as economical relative to forced flow systems.
As far as the boilers themselves, normally a water-tube
boiler is more efficient than a fire-tube boiler. As far as
choice of fuels for the boiler, it will depend on the individual
location and specific heating needs.
Use of Electric Heaters
The high cost of electric heating almost disqualifies it as
a major source of full-time heating. However, it is a viable
116
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alternative when: (1) low cost electric power is available;
(2) in very isolated locations where transporting fuels is a
problem; (3) very intermittent use is required; (4) supplementary
heating is needed, therby allowing a small heating system
to be adequate for a majority of the time in lieu of a large
system with a great deal of excess capacity; or (5) a heat
pump is utilized with an assist from solar or low-grade waste
heat discharged from a power generating station.
Fuel Prices
Table 3 is an approximate listing of various fuel costs
in the Northeast area and for the most part assumes bulk purchases
(as of August 1977).
Table 3. Cost of Common Fuels
Regular Gas
Premium Gas
Unleaded Gas
Kerosene
#2 Heating Oil
#4 Fuel Oil
#6 Fuel Oil
Diesel
LP Gas
Natural Gas
Residential
Commercial
Wholesale
**Coal
63.9C/gal*
69.9C/gal
66.9<=/gal
48.6
-------
Criteria:
h = overall heat transfer coefficient - BTU/ft2 hr °F
1.15-1.2 for glass
1.00-1.2 for polyethylene
.8 for double filmed polyethylene
0
A = surface area for each type of cover, ft"
td = indoor design temperature [normally 15°C (60°F)], °F
to = outdoor design temperature [-(23.5-29)°C (-(10-20)°F)]
for most areas within the Northeast],°F
After calculating the heat loss, add an additional 10% to
the final total to account for infiltration. This procedure
should give a satisfactory estimate although there are more
exact means. The heat loss figure obtained at this point is
the maximum loss that needs to be designed for, and it is this
figure that is used to select a furnace unit. The design tem-
peratures are the key to this equation. The outdoor design
temperature is the mean of extremes based on weather data.
The indoor design temperature is based on normal greenhouse
practice and depends on the plants grown.
Estimating Fuel Costs for Seasonal Operation
Once the heating requirements have been determined, the next
step is to estimate the seasonal costs of heating. The method
used here is ASHRAE's "Calculated Heat Loss Method." Basically,
it takes the design heat loss and adjusts it according to local
conditions. In other words, one would not expect to operate at
the extreme design point all winter long.
The first step in this method, then, is to take the design
heat loss, "M", and place it into the following equation to
obtain an average heating requirement for the period under con-
sideration.
X = M(t-ta) (2)
(td-t0)
Criteria;
t = average inside temperature grower wants to
maintain during the heating period (°F)
ta = average outside temperature during estimate period
(with October 1 - May 1 heating season). (ASHRAE
Guide lists these by city.)
td = inside design temperature, 15°C (60°F)
t0 = outside design temperature, -23.5°C (-10°F)
118
-------
The quantity of fuel used is equal to F and
F = XN (3)
EC
Criteria;
X = average heating requirement for the period under
consideration
N = number of heating hours in the estimate period (i.e.,
October 1 - May 1, figuring 212 days x 18 hours/day
for heating needed = 3816 hours).
E = efficiency of utilization of the fuel over the
period expressed as a decimal (Table 1).
C = heating value of one unit of fuel or energy
(See Table 4).
Then, knowing the price of fuel (or using a value in
Table 3), multiply the price times F to obtain the approxi-
mate cost of fuel in a given year.
Table 4
Values of C = heating value of one unit of fuel or energy
Average Heating Value Average Weight
Fuel BTU/gal BTU/lb Ib/gallon
Gasoline
Kerosene
#2 Fuel oil
#4 fuel oil
#5 light fuel oil
#5 heavy fuel oil
#6 fuel oil
Butane
Propane
Coal (bituminous)
Methane (Natural gas)
123,769
130,637
139,400
145,600
148,400
150,700
153,600
98,832
87,959
1000 BTU/ft3
20,125
19,155
19,557
19,178
18,994
18,873
18,616
20,420
20,745
12,500
1000 BTU/ft3
6.15
6.82
7.128
7.592
7.813
7.985
8.251
4.84
4.24
From 1972 ASHRAE Handbook of Fundamentals, p. 234, 239.
119
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APPENDIX D
ORNAMENTAL HORTICULTURE
USING BIOGAS BOOSTED GREENHOUSES
James D. Batson
Dartmouth College
Hanover, New Hampshire 03755
Linda S. Halstead
University of Vermont
Burlington, Vermont 05401
121
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CONTENTS
Page
Simulation of Greenhouse Operation 125
Summary of Program Output 126
Description of Variables 12 7
Flow Chart of the Model 128
Greenhouse Modeling Program
ANNEX TO APPENDIX D
Heat Loss Calculations for Greenhouse No. 4
145
123
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APPENDIX D
SIMULATION OF GREENHOUSE OPERATION
The following program analyzes the profits from the growth
of roses in Cornell-designed greenhouse No. 4. This greenhouse
is heated with biogas heaters using fuel from anaerobic digesters
which are constructed adjacent to the greenhouses.
Marketing information for the program was provided by the
Montgomery Rose Company of Hadley/ Massachusetts. Costs for
operating an anaerobic digester were obtained from the report
"Process Feasibility Study Flow: The Anaerobic Digestion of
Dairy Cow Manure at the State Reformatory on a farm in Monroe,
Washington". This was prepared by the ECOTOPE Group, Research
Consultants, P.O. Box 559, Seattle, Washington, 98105. Other
economic data were obtained from the "Waste Heat Utilization
Demonstration Greenhouse Design Concept" (see Appendix C).
A detailed flowchart of the model follows. It should be
noted, however, that some parameters are not included in the
model and must be calculated separately. The initial costs of
site work, utilities, etc. are not included in the simulation.
Also, profits from the sale of concentrated fertilizer produced
by the biogas converter have not been calculated.
The program is written in FORTRAN; it has been designed to
be executed in an interactive mode on the Honeywell Time Sharing
system available at the University of Vermont. Results from the
program are summarized in the following table.
125
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TABLE 1
SUMMARY OF PROGRAM OUTPUT
No. Initial Initial Annual Annual Income Income
of Cost of Cost of Operation Operation From From Total Total
Green- Green Digester Cost of Cost of * Sale of Sale of Income Cost
houses house Greenhouse Digester Roses Biogas
Heated 2 50,770 71,0^0 26,131 23,630 25,920 3221 29.1M 50,^6
Summer 2
Heated 3 50,770 71,0^0 27,789 23,630 31,680 2804 3^,W 52,170
Summer 1
Heated ^ 50,770 71,0^0 29,^6 23,630 37, W 2666 40,106 5**
Summer 0
Summer greenhouse will only operate 20 weeks out of the year. The heated greenhouse will
operate year-around. Other income may be derived from the sale of excess methane which
may amount to 860,000 cf per year.
Note
* Engineer wages for running digester and methane gas plant have been included.
-------
Variable Name
Table 2 - Description of Variables
Meaning
Initial
Value
SQFT
CSTGRN
CSTHDH
CSTOPN
CSTGAS
CSTDIG
CSTPMP
OPBTU
NOPBTU
SALHOR
SALPRT
CSTEXT
SALENG
PCTSWT
PCTFOR
NUMROS
NUMSWT
NUMFOR
PRCSWT
PRCFOR
INTCAP
LIFDIG
LIFGRN
1560 Sq. ft. of space in each greenhouse
7355 Initial cost per greenhouse
18000 Initial cost of headhouse
837.50 Cost of operational equipment per
greenhouse
.22 Cost of supplemental natural gas
per 100 cubic feet
7104-0 Initial cost of digester
2.08 Cost of pumping 200 gpm of water
from plant to digester per day
1000 Number of BTU's generated per hour
per cow if plant is operational
625 Number of BTU's generated per hour
per cow if plant is not operational
9600 Salary of one horticulturist
1650 Salary of part time workers per
greenhouse
10^3.75 Cost of extras per greenhouse
(fertilizers, plants, pesticides,etc)
12000/yr Salary of an engineer
33.33% Per cent of roses which are Sweetheart
66.67% Per cent of roses, Forever Yours
672 Number of roses in a greenhouse
23 Number of Sweetheart blooms per rose
per year
36 Number of Forever Yours blooms per
rose per year
1.25 Price for one Sweetheart rose
.52 Price for one Forever Yours rose
.095 Interest rate
50 Estimated life of digester (years)
25 Estimated life of greenhouse (years)
127
-------
FLOW CHART OF THE MODEL
INITIALIZE ALL
COST VARIABLES -
SEE TABLE 1
BTUNAV
8TLHRS
BTUEXS
ooo
n n H
TOTDAY - 0
DHNDAY - 0
CALC. AMORTIZATION
RATES FOR GREENHOUSE
AND DIGESTER
INPUT:
g OF COWS
# OF GREEN-
HOUSES
# OF HORTI-
CULTURISTS
COST OF DIGESTER
- SCALED AS IN
ECOTOPE REPORT
COST OF GREENHOUSES '
COST OF HEADHOUSE
+NOGRN * COST PER
GREENHOUSE
WEEK
= 1
CALC. BTU NEEDED
BY HEAT LOSS
FORMULA (APP. Dl)
E
DAY-
1
TOTDAY - TOTDAY + 1
CSTH20 -
CSTH20 + CSTPHP
DAYBTU - OPBTU
0© O
DWOAY.-
DAYBTU
DWNDAY+ 1
= NOPBTU
128
-------
FLOW CHART OF THE MODEL (CONT.)
CALC. # BTU'S AVAIL
FROM DIGESTER PER
GREENHOUSE
BTUNAV = BTUNAV +
24 * (BTU»5 NEEDED -
BTU'S AVAILABLE)
BTUHRS = BTUHRS +
24 * NO. GREEN * BTU
BTU'S AVAIL:
BTU'S NEEDED
BTUEXS= BTUEXS +
24 » (BTU'S AVAIL -
BTU'S NEEDED)
BTUHRS= BTUHRS +
24 * NO. GREEN * BTU
BTUHRS -
BTUHRS + 24 *
NO. GREEN * BTU
DAY
= DAY J
^ 1
YES
WEEK =
WEEK + 1
YES
129
-------
FLOW CHART OF THE MODEL (CONT.)
ANN. GREENHOUSE COST =
SALARY OF HORTICULTURISTS +
SALARY OF PART-TIMES +
COST OF EXTRAS + AMORT.
ANN. DIGESTER COST =
COST OF DIGESTER +
SALARY OF ENGINEER +
AMORTIZATION
SUP. FUEL COST =
BTU'S NOT AVAIL * COST OF FUEL
PROFIT
APPROX. BY
SO. FT.?
ANN. INCOME -
(NO. GREEN * SQ. FT.
» PROFIT) +(20/52)
* (NO. SUMMER »
SQ. FT. * PROFIT)
PROFIT - INCOME ROM
SWEETHEARTS + INCOME
FROM FOREVER YOURS
ANN. INCOME =
(NO. GREEN * PROFIT)
+ (20/52) * NO.
SUMMER • PROFIT ,
PRINT ALL
RESULTS
AJIN. INCOME FROM GAS •
2.50 » (BTUEXS/1.E6)
i
STOP
130
-------
1 t Q« ««•««•««««*««*«**»»<»»*»*»«»»»»*»»*»»»»*•«*»«**»«*««**«*««*«**
2. C
3. C GREENHOUSE MODELING PROGRAM
1. C
5. c««««««»««*«*i«*««»*«t******«*«»«*««*tt«*«*«**«*«*«»««*««***««*«
6. C THIS PROGRAM IS AN ECONOMIC MODEL OF A GREENHOUSE COMPLEX BEING
7. C HEATED BY BIOGAS PRODUCED BY A FARM WHICH HAS A DIGESTER WHICH
8. C IS PREHEATED BY WASTE HEAT FROM A POWER PLANT.
9. C
10. C SOURCES ARE:
11. C 1. WASTE HEAT UTILIZATION DEMONSTRATION GREENHOUSE DESIGN CONCEPT
12. C PREPARED BY: D. R. PRICE, PHD
13- C 2. PROCESS FEASIBILITY STUDY: THE ANAEROBIC DIGESTION OF DAIRY COW
11. C MANURE AT THE STATE REFORMATORY HONOR FARM MONROE, WASHINGTON
15. C PREPARED BY: ECOTOPE GROUP, RESEARCH CONSULTANTS
16. C - PARAMETRIX INC., PROJECT ENGINEERS
17. C "3. TED JOHNSON, MONTGOMERY ROSE CO. (HADLEY, MA.)
18. C
i g m £•»«*»»*»«*»****«««««»«•«««««»««*•*«««*«««•«**«*«**«*«««***««««
20. REAL INTCAP.MAXACR
21. INTEGER 0 (52),CODE,CODPRO,INDEX,DAY,WEEK
22. C AVERAGE WEEKLY TEMPERATURES AT GREENHOUSE SITE.
23. INTEGER Q/-15,-15,-15,35,30,-15,-15,-15,40,H8,35,M2,5U,HO,HO,65,
2M. 1 38,43,50,52,52,66,58,66,70,77,70,66,75,70,77,66,68,79,59,
25. 2 63,60,52,5H.62.U6,HO,HO,-15,32,50,-15,-15,-15,-15,327
26. C DATA FOR SCALING DIGESTER COST
27. C SEE CHART ON PG. 87 OF REF 2 ABOVE
28. C UNITS IS CATTLE UNITS
29. C MULT IS MULTIPLIER
30. C MTHCST IS MONTHLY COST
31 . C
32. REAL UNITS(5),MULT{5),MTHCST(5)
33- DATA UNITS /350,525,700,875,1050/
3H. DATA MULT / 1 . 0000 , 1 . 2754 , 1 . 5260 , 1 . 7H88 , 1 . 95H5/
35. DATA MTHCST /H00.76 , 511.1H, 611.56,700.85,783.29/
36. C**************************************************************
-------
37. C
38. C VARIABLES FOR COST OF THE GREENHOUSE
39. C
tO. C SQUARE FEET OF GROWING SPACE PER GREENHOUSE
11. C GREENHOUSE SIZE IS 26 FT. BY 60 FT. OR 1560 SQ FT.
*»2. SQFT = 1560
43. C COST PER GREENHOUSE (DESIGN * 4)
44. CSTGHN * 7355.00
45. C COST FOR THE HEADHOUSE
16. CSTHDH = 18000.00
•47. C COST OF OPERATIONAL EQUIPMENT PER GREENHOUSE
*»8. CSTOPN s 3350.00/4
49. C COST OF SUPPLEMENTAL NATURAL GAS PER 100 CUBIC FEET
50. CSTGAS = .22
51. c**************************************************************
52. C
53. C VARIABLES FOR COST OF THE DIGESTER
54. C
55. C COST OF DIGESTER IN WASHINGTON (TOTAL PROJECT COST)
56. C SEE PG. 73-74 OF REF # 2 ABOVE
57. CSTDIG = 710UO.OO
58. c***************»*•••*»•»••**•»»»»»«»*•»«•»»»»»«»»••»«*»*«•«*»*
59. C
60. C VARIABLES FOR DAY-TO-DAY OPERATION
61 . C
62. C COST OF PUMPING 200 GPM OF WATER FROM PLANT TO DIGESTER
63. C PER DAY BASED ON N = 30 AND .04/KWH
61. C
65. CSTPMP = 2.08
66. C INITIAL COST OF PUMPING WATER TO PLANT IS ZERO
67. CSTH20 = 0
68. C NO. OF BTU'S /HR/COW IF PLANT IS OPERATIONAL
69. OPBTU s 1000
70. C NO. OF BTU'S /HR/COW IF PLANT IS NOT OPERATIONAL
71. NOPBTU = 625
72. c
-------
73. C
7^. C VARIALES FOR ANNUAL OPERATION OF GREENHOUSE
75. C
76. C SALARY OF HORTICULTURIST
77. SALHOR = 9600.00
78. C COST OF PART-TIME MAINT AND.WORKERS PER GREENHOUSE
79. , SALPRT = 6600.00/4
80. C COST OF FERTILIZERS, PESTICIDES, VEHICLE, ELECTRICITY,
81. C PLANTS,SEEDS,ETC. PER GREENHOUSE
82. CSTEXT = 4175.00/4
83. C NUMBER OF GREENHOUSES A•HORTICULTURIST CAN HANDLE
8U. GRNHRT = U
85. C SALARY OF AN ENGINEER
86. SALENG = 12000.00
87. C
88. C VARIABLES FOR ANNUAL INCOME FROM ROSES
89. C
M 90. C ALLOW USER TO INPUT PROFIT PER SQ. FT OR LET PROGRAM CALCULATE
92. WRITE(6,700)
93. 700 FORMAT('ODO YOU WISH TO INPUT PROFIT PER SQ. FT. OR HAVE1,
94. 1 ' THE PROGRAM CALCULATE AN ESTIMATED PROFIT'/
95. 2 ' ENTER 1 FOR ESTIMATING NOW OR 2 FOR PROGRAM CALCULATION1)
96. 705 READ(5,45) CODE
97. IF (CODE .EQ. 1) GO TO 710
98. IF (CODE .EQ. 2) GO TO 720
99. WRITE (6,35)
100. GO TO 705
101. C USER WISHES TO. INPUT PROFIT PER SQ. FT.
102. 710 WRITE (6,730)
103. 730 FORMAT('CENTER ESTIMATE OF PROFIT PER SQ. FT'/
104. . 1 ' ENTER NUMBER WITHOUT DOLLAR SIGN AS DOLLARS AND CENTS')
105. READ(5,45) PROFIT
106.
107. C INDICATE SQ FT PROFIT ESTIMATE
108. CODPRO = 1
109. C
-------
110. UU TU Y*»U
111. C CALCULATE PROFIT INTERNALLY
112. 720 CODPRO z 0
113. C PER CENT OF ROSES WHICH ARE SWEETHEART
114. PCTSWT s .3333333
115. C PER CENT OF ROSES WHICH ARE FOREVER YOURS
116. PCTFOR r .6666667
117. C NUMBER OF ROSES PER GREENHOUSE SPACING AT 12 INCHES
118. C (IF SPACING IS 11 INCHES THIS SHOULD BE 725)
119. NUMROS = 672
120. C NUMBER OF FLOWERS PER PLANT PER YEAR (SWEETHEART)
121. NUMSWT = 23
122. C NUMBER OF FLOWERS PER PLANT PER YEAR (FOREVER YOURS)
123. NUMFOR = 36
124. C PRICE FOR SWEETHEART ROSES
125. PRCSWT = 1 .25
126. C PRICE FOR FOREVER YOURS ROSES
127. PRCFOR s .52
128. C
129. C CALCULATE AMORTIZATION RATES
130. C INTEREST RATE FOR CAPITAL RECOVERY FACTOR
131. 740 INTCAP s .095
132. C LIFE OF THE DIGESTER (YEARS)
133. LIFDIG = 50
134. C LIFE OF THE GREENHOUSES (YEARS)
135. LIFGRN = 25
136. C
137. C R1 IS FOR DIGESTER; R2 IS FOR GREENHOUSES
138. C
139. R1 = INTCAP » (1 + INTCAP) •« LIFDIG/((1 +INTCAP)»«LIFDIG -1)
140. R2 = INTCAP • (1 + INTCAP) »« LIFGRN/((1 + INTCAP)»«LIFGRN -1)
141. C*•••«»»»«*»«»»»»»««f»»»t»»«i»»»«««t«««»«»»««««»»»»»*««»«i««»»«
-------
1 42.
143.
144.
145.
146. .
147.
148.
1 49.
150.
151 .
152.
153.
154.
155.
156.
157.
158.
159.
160 .
161 .
162.
163.
164.
165.
166.
167 .
168.
169.
170.
171.
172.
173.
174.
175.
176.
177.
C
C
C
C
C
11
C
1
2
C
1
2
3
C
3
C
1
4
4
FIGURE OUT HOW MANY GRENHOUSES YOU CAN OPERATE
ALLOW NO. OF COWS AND NO. OF GREENHOUSES TO VARY
WRITE(6,10)
) FORMATCOHOW MANY COWS ARE THERE ON THE FARM (1 COW = 1250 '
1'LB. OF CATTLE)')
READ(5,45) NOCOWS
NEED 200 COWS PER GREENHOUSE
MAXGRN = NOCOWS / 200
WRITE(6,15) MAXGRN
5 FORMATCOYOU MAY SUPPORT' , 15 ,' GREENHOUSES')
MAXACR = (MAXGRN * SQFT)/43560.
WRITE(6,20) MAXACR
0 FORMATC THIS IS EQUIVALENT TO ',G,' ACRES')
100
25
1
WRITE(6,25)
FORMAT('OWOULD YOU LIKE TO ENTER THE
,' OR GREENHOUSES (2)•/T10,'(ENTER 1
DESIRED
OR 2)')
AREA IN ACRES (1)'
CODE
TO
TO
1 10
120
READ(5,30)
30 FORMAT(II)
IF (CODE .EQ. 1) GO'
IF (CODE .EQ. 2) GO
CODE ENTERED IN ERROR
WRITE(6,35)
35 FORMAT('OCODE MUST BE ENTERED AS A 1 OR 2'/
1,'PLEASE REENTER')
GO TO 100
PROCESS AREA IN ACRES
110 WRITE(6,40)
40 FORMATCOHOW MANY ACRES DO YOU WISH TO CULTIVATE')
READ(5,45) ACRREG
45 FORMAT(G)
NOGRN = (ACRREG*43560)/SQFT +.5
GO TO 130
-------
178. C PROCESS AREA IN NUMBER OF GREENHOUSES
179. 120 WRITE(6,50)
160. 50 FORMATCOHOW MANY GREENHOUSES WOULD YOU LIKE1)
181 . READ(5,15) NOGRN
182. 130 WRITE(6,55) NOGRN
183. 55 FORMATCOYOU HAVE' ,15,' GREENHOUSES')
181. C SEE IF MORE THAN WE CAN SUPPORT
185. IF(NOGRN .GT. MAXGRN) WRITE(6,60) MAXGRN
186. 60 FORMATf'ONOTE: YOUR SYSTEM CAN ONLY SUPPORT .',15,
187. 1 ' HEATED GREENHOUSES WITHOUT SUPPLEMENTAL HEAT1)
188. C CHECK FOR SUMMER GREENHOUSES - NO EXTRA HEAT REQUIRED
189. 110 WRITE(6,65)
190. 65 FORMATCOWOULD YOU LIKE ANY SUMMER GREENHOUSES (THESE ARE '
191. 1 ,'HOUSES WHICH ONLY OPERATE IN THE SUMMER, WHICH IN TURN, f
192. 2 ,' REQUIRE NO EXTRA HEAT)1/1 ENTER 1 FOR YES, 2 FOR NO1)
193. NOSUM = 0
191. READ (5,30) CODE
195. IF (CODE .EQ. 1) GO TO 150
196. IF (CODE .EQ. 2) GO TO 170
197. WRITE(6,35)
198. GO TO 110
199. C PROCESS SUMMER GREENHOUSES
200. 150 WRITE(6,25)
201. READ(5,30) CODE
202. IF (CODE .EQ. 1) GO TO 160
203. IF (CODE EQ. 2) GO TO 180
201. C CODE ENTERED IN ERROR
205. WRITE(6,35)
206. GO TO 150
207. C PROCESS SUMMER GREENHOUSES IN ACRES
208. 160 WRITE(6,10)
209. READ(5,15) ACRSUM
210. NOSUM = (ACRSUM • 13560)/ SQFT + .5
211. GO TO 170
212. C PROCESS SUMMER GREENHOUSES IN NUMBER OF GREENHOUSES
213. 180 WRITE(6,70)
211. 70 FORMATCOHOW MANY SUMMER GREENHOUSES WOULD YOU LIKE')
215. READ(5,15) NOSUM
216. 170 WRITE(6,75) NOSUM
217. 75 FORMATCO YOU HAVE',15,' SUMMER GREENHOUSES')
-------
,
218. C
219. C INPUT THE NUMBER OF HORTICULTURISTS
220. WRITE(6,80) GRNHRT
221. 80 FORMATCOHOW MANY HORTICULTURISTS DO YOU WANT FOR THE YEAR ',
222. 1'ROUND GREENHOUSES (1 PER', 15,' GREENHOUSES IS RECCOMMENDED ' )
223. READ(5,45) REGHOR
224. C CHECK IF SUMMER GREENHOUSES
225. IF (NOSUM .EQ. 0) GO TO 200
226. C HAVE SUMMER GREENHOUSES
227. WRITE(6,85)
228. 85 FORMATCOHOW MANY HORTICULTURISTS DO YOU WANT FOR THE1
229. 1,' SUMMER GREENHOUSE')
230. READ(5,45) SUMHOR
231 • GO TO 210
232.
233.
234.
235.
236.
237.
238.
239.
240.
2*41 .
242.
213.
244.
245.
246.
247.
248.
249.
250.
251 .
252.
253.
254.
255.
256.
c
NO SUMMER GREENHOUSES
200 SUMHOR = 0
2 i
90
C
C
C
C
c
c
c
c
c
c
c
c
c
c
c
0 WRITE(6,90) REGHOR, SUMHOR
FORMATCOYOU HAVE ',13,' HORTICULTURISTS FOR THE ',
VYEAR ROUND GREENHOUSES AND '13,'
2'SUMMER GREENHOUSES')
HORTICULTURISTS FOR THE
ALL DATA ENTERED - NOW START THE SIMULATION
INITAILIZE RANDOM NUMBERS FOR POWER
CALL RANDOM( 1 ,IY,RAND)
IX = IY
INITIAL COST OF ALL GREENHOUSES
INTGRN = CSTHDH + (NOGRN + NOSUM)
PLANT UP CALCULATIONS
* (CSTGRN + CSTOPN)
INITIAL COST OF DIGESTER - REFER TO PG. 85-89 OF REF . # 2 ABOVE
CONVERT COW UNITS TO DIGESTER CATTLE
NOTE: ONE DIGESTER COW UNIT IS 100
ORIGINAL COW ASSUMED AT 1250
UNITS
0 LB OF CATTLE
LBS
-------
257. C
258. CATUNT a (1250./1000) * NOCOWS
259. SAVUNT = CATUNT
260. C CALCULATE HOW MANY SEPARATE UNITS ARE NEEDED
261 . C
262. C FIRST ASSUME ONE DIGESTER
263. C
264. NODIG = 1
265. C
266. 215 DO 220 INDEX = 1,5
267. IF (CATUNT .LE. UNITS(INDEX)) GO TO 230
268. 220 CONTINUE
269. C NEED MORE DIGESTERS - TRY ONE MORE
270. C
271. NODIG = NODIG + 1
272. C MODIFY CATTLE UNITS TO REFLECT NEW DIGESTER
273. CATUNT = SAVUNT / NODIG
27^. GO TO 215
M 275. C
w 276. C INDEX POINTS TO SIZE OF THE DIGESTER
277. C CALCULATE INITIAL DIGESTER COST
278. C
279. 230 INTDIG = NODIG • (MULT(INDEX)*CSTDIG)
280. Q«•»•»«»•»•«»»»««*«»»»»»»»»»»»»»»•»••«»•»»•»»«»»««»•«««««•*««»«
281, C
282. C SIMULATE DAY-TO-DAY OPERATION
283. C
28U. C NOTE: THESE COMPUTATIONS ARE FOR ONE GREENHOUSE
285. C
286. C BTUNAV - BTU'S NEEDED IN EXCESS OF DIGESTER OUTPUT (FOR 1 GREENHOUSE)
287. C BTUHRS - * OF HOURS OF PUMPING GAS FROM DIGESTER TO 1 GREENHOUSE
288. C (1 HR. IS PUMPING 200000 BTU TO 1 GREENHOUSE)
289. C BTUEXS - EXCESS BTU'S PRODUCED BY THE DIGESTER
290. C
291. C SET COUNTERS TO ZERO
292. BTUNAV s 0
293. BTUHRS s 0
294. BTUEXS = 0
295. C
-------
10
10
296.
297.
298.
299.
300.
301 .
302.
303.
304.
305.
306.
307.
308.
309.
310.
311.
312.
313.
314.
315.
316.
3U.
318.
319.
320.
321.
322.
323-
324.
325.
326.
327.
328.
329-
330.
331 .
332.
333.
334.
C TOTDAY - TOTAL NUMBER OF DAYS
TOTDAY = 0
C DWNDAY - TOTAL NUMBER OF DAYS PLANT IS DOWN
DWNDAY = 0
C PROCESS FOR ALL WEEKS IN A YEAR
DO 310 WEEK = 1 , 52
C
C CALCULATE HEAT LOSSES
TMP1 = 57.5 - O(WEEK)
C CHECK IF NO BTU'S REQUIRED
IF (TMP1 .LE. 0) GO TO 250
TMP2 = 30
IF (Q(WEEK) .LE. TMP2) GOTO 240
TMP2 s Q(WEEK)
C CALC HEAT LOSS BY HEAT LOSS FORMULA IN APPENDIX
240 BTU = 80*(57.5-TMP2)-»-TMP1*(212. 4 + 457+53+219)
GO TO 260
C NO HEAT REQUIRED
250 BTU = 0
260 CONTINUE
C
C GO THROUGH SEVEN DAYS PER WEEK
C
DO 310 DAY = 1 , 7
C INCREMENT DAY COUNTER
TOTDAY = TOTDAY + 1
C IS PLANT UP TODAY
CALL RANDOM(IX,IY,RAND)
IX = IY
IF (RANDMOO .LE. 90) GO TO 270
C NO -- PLANT IS DOWN - BOOST DOWN DAYS
DWNDAY = DWNDAY + 1
C AND AMOUNT OF BTU'S /COW PRODUCED IS REDUCED
DAYBTU = NOPBTU
GO TO 280
C PLANT IS UP -- PUMP WATER FROM PLANT TO DIGESTER
270 CSTH20 = CSTH20 + CSTPMP
DAYBTU = OPBTU
-------
*.
0
335.
336.
337.
338.
339.
3*0«
3*3.
3**.
3*5.
3J16-
3*7.
3*8.
3*9.
350.
351-
352.
353.
35U.
355.
356.
357.
358.
359.
360.
361.
362.
363.
36*-
365.
366.
367.
368.
369.
370.
371.
372.
C CALC NUMBER OF BTU'S AVAILABLE FOR GREENHOUSE
280 TEMP s NOCOWS • DAYBTU /NOGRN
IF (BTU .NE. TEMP) GO TO 290
C BTU NEEDED AND AVAILABLE ARE THE SAME
C MORE GAS TO THE GREENHOUSES
BTUHRS r BTUHRS + 2*4 • BTU » NOGHN
GO TO 310
C BTU NEEDED AND AVAIL ARE NOT THE SAME
290 IF (BTU .LT. TEMP) GO TO 300
C * BTU'S REQUIRED ARE MORE THAN AVAILABLE
C PUMP AS MUCH AS POSSIBLE TO GREENHOUSES
BTUNAV = BTUNAV + 2*
BTUHRS s BTUHRS + 2*4
GO TO 310
C # BTU'S REQUIRED LES THAN THE AVAILABLE -
C CALC EXCESS GAS
• ( ( BTU«NOGRN)- (NOCOWS»DAYBTU) )
«(NOGRN »TEMP)
300
310
C
C ANNUAL
C
CONTINUE
BTUEXS
BTUHRS
= BTUEXS
* BTUHRS
2* * ( ( NOCOWS'DAYBTU)- ( BTU*NOGRN) )
2* • NOGRN • BTU
COST OF GREENHOUSES
C
C
C
C
C
C
C
C
C
C
ANGRN s SALHOR « REGHOR + SALHOR • (20. /52) +
1 NOGRN » (SALPRT + CSTEXT) +
2 NOSUM«(SALPRT+CSTEXT)«(20./52) +
3 R2 • INTGRN
ANNUAL COST OF DIGESTER
ANDIG r NODIG » (12 »MTHCST( INDEX) ) 4 SALENG + R1 » INTDIG
COST OF SUPPLEMENTAL FUEL
ANSUP s BTUNAV / 1000 • CSTGAS / 100
ANNUAL INCOME FROM ROSES
IS ESTIMATE .PER SQ FT OR INTERNALLY CALCULATED
-------
373.
371.
375.
376.
377.
378.
379.
380 .
381.
382.
383.
381.
385.
386.
387.
388.
389.
390.
M 391 .
H 392.
393.
391.
395.
396.
397.
398.
399.
100.
101 .
102.
103.
101.
105.
106.
107.
108.
109.
110 .
111 .
C
C
C
C
C
C
C
3
C
C
C
C
C
C
C
C
C
C
C
3
5
5
5
5
5
IF (CODPRO .EQ. 1) GO TO 330
ANINC = NOGRN *{PCTSWT « NUMROS * NUMSWT * PRCSWT +
1 PCTFOR * NUMROS * NUMFOR * PRCFOR)
C ANNUAL INCOME FROM SUMMER GREENHOUSES
ANSUM = NOSUM *(PCTSWT*NUMROS*(20./52)«NUMSWT*PRCSWT +
1 PCTFOR*NUMROS*(20./52)*NUMFOR«PRCFOR)
GO TO 310
C CALCULATE PROFIT BY SO. FT.
ANINC = NOGRN * SOFT * PROFIT
ANSUM = NOSUM * SOFT * PROFIT * (20./52)
C CALCULATE INCOME FROM SALE OF EXCESS GAS
AT 2.50 PER 10 TO THE SIXTH BTUS
ANGAS = 2.50 * (BTUEXS / 1.E6)
C PRINT THE RESULTS
COSTS FIRST
310 WRITE(6,500) INTGRN
500 FORMATCOTHE INITIAL COST FOR THE GREENHOUSE COMPLEX IS $',I8)
WBITE(6,510) NODIG.INTDIG
510 FORMAT('OTHE INITIAL COST FOR THE DIGESTER COMPLEX OF ',
1 II,' DIGESTERS IS $',18)
WRITE(6,520) ANGRN
520 FORMATCOTHE ANNUAL RUNNING COSTS FOR THE GREENHOUSES IS $',I8)
WRITE(6,530) ANDIG
530 FORMATCOTHE ANNUAL RUNNING COSTS FOR THE DIGESTER IS $',I8)
WRITE(6,510) CSTH20
510 FORMATCOTHE ANNUAL COST FOR PUMPING WATER FROM THE PLANT TO ',
1 'THE DIGESTER IS $',18)
-------
412.
413.
414.
415.
416.
417.
418.
419.
420.
421.
422.
423.
424.
425.
426.
427.
428.
429.
430.
431 •
432.
433.
434.
435.
436.
437.
438.
439.
440.
441.
442.
443.
444.
445.
446.
550
560
C
C NOW
C
570
582
580
590
600
610
C
C
620
630
WRITE(6,550)
FORMAT* 'OTHE
TOT = ANGRN •
WRITE(6,560)
FORMAT('OTHE
ANSUP
ANNUAL
• ANDIG
TOT
TOTAL ANNUAL
COST OF SUPPLEMENTAL
+ CSTH20 + ANSUP
FUEL IS *',18)
COST OF OPERATION IS $',I8)
COMPUTE THE INCOMES
TOT = ANINC + ANSUM
WRITE(6,570) TOT
FORMATCO THE ANNUAL INCOME FROM ROSES IS $',I8)
WRITE(6,582) ANGAS
FORMATCOTHE ANNUAL
WRITE(6,580) BTUHRS
FORMATCOTHE NUMBER
1» DIGESTER TO ALL THE GREENHOUSES IS
WRITE{6,590) BTUNAV
FORMATCOTHE NUMBER OF
1 'AVAILABLE WERE',G)
WRITE(6,600) BTUEXS
FORMATCOTHE NUMBER OF EXCESS BTUlfS PRODUCED
1 'BY THE DIGESTER WERE:1 ,G)
WRITE(6,610) DWNDAY.TOTDAY
FORMAT('OTHE PLANT WAS NOT OPERATIONAL
1' DAYS' )
INCOME FROM BIOGAS IS $',I8)
OF BTU''S WHICH WERE PUMPED FROM THE
1 .0)
BTU1'S NEEDED THAT WERE NOT ',
5, ' OF THE TOTAL1 ,15
M5,'
PERCNT = 100. * (DWNDAY/TOTDAY)
WRITE(6,620) PERCNT
FORMATCO ' ,T10,'THIS AMOUNTS TO
WRITE(6,630)
FORMAT('OINCOME NOT INCLUDED IN THE SIMULATION
1 ' SALE OF EXCESS METHANE AND THE DRIED SLUDGE
CALL EXIT
END
PERCENT OF THE TIME')
INCLUDES THE1
AS FERTILIZER1)
-------
1. SUBROUTINE RANDOM (IX.IY.YFL)
2. IY=IX*65539
3- IF(IY)5,6,6
H. 5 IY=IY+21U74836M7+1
5. 6 YFL=IY
6. YFL = YFL*.il6566l3E-9
7. RETURN
8. END
LJ
-------
ANNEX TO APPENDIX D
HEAT LOSS CALCULATIONS FOR GREENHOUSE NO. I*
by Joe Kent
General Heat Loss Equation
Q= UAAT
&T= To-Ti
u-l
Floor Losses
Air
porous cone
R= 0.62
R= 3-33
6" of 5/8 "Si™ R-0.87
Stone
2" styrofoam
polyethylene-
earth
R =1.09
vinyl liner
—>R =12.5
—> R =1.09
ZR=19.50
Minimum temp, for earth = 30°F
Q = UA
k- TG) Win. value
(26)(60)(57.5-3^)
Qp=
Qp = 80 57.5-Q(W)
Q(W) For earth not
less than 30*F
BTU/hr
RTn
in
60
26'
TQ = 30*F for
greater
Ground Temp.
Minimum = 30°F
145
-------
Losses for Greenhouse
Insulated roof
Glass or plastic
lined
R = 0.17
plywood R =0.93
Air space R =2.80
R = 0.62
iBase walls
A=(16)(60)= 960 sq.ft.
ZR -
Heat loss Q0 = UA
- TA) =
(960) (Ti - TA)
.*f (Ti - TA) •«- Q roof
BTU/hr
Glass or Plastic Lined
Heat loss ="
R = 0.17
Double plastic
Air R = 0.62
(60) +15
=1275 sq.ft.
Tft = 2.79
70 (1275) (Ti-TA)= ^57 (Ti-TA) «r-Roof liner
2.79 A - 2_ BTU/hr
Base Wall
Same R as roof R = ^.52
QBW = 5752 <2l*0>
-------
Infiltration losses
Ambient air temperature = 50°F
Specific Heat Air = .
BTU/lb.°F
1C, = £1 1 = RT - (53.3) (460 + 50) _
P y P (14.7) (144)
Infiltration <**/change/hour
Volume = 26(2)(60)+261111(60) = 11,700 cf
2
Heat lost to infiltration
=(0.24)(ll,700)(.078)(Ti-TA)
= 219(T.-T ) BTU/hr
J- -f\
= 0.078 Ib/cf
Floor QF = 80 157-5 -Q(W)]
Roof QR = 212.^(Ti-TA)
SUMMARY OF LOSSES
Q(W)> 30
Glass QG =
(Ti-TA)
Base Wall QBW = 53 (Ti-TA)
Infiltration Qj - 219 (Ti-TA)
Total
(212.4 + 457 + 53 + 219)
147
-------
TECHNICAL REPORT DATA
(Please read Instructions on the reverse before completing)
1. REPORT NO.
EPA-600/7-79-091
2.
3. RECIPIENT'S ACCESSION-NO.
4. TITLE AND SUBTITLE
Nuclear Power Plant Waste Heat Horticulture
S. REPORT DATE
March 1979
5, PERFORMING ORGANIZATION CODE
7. AUTHOR(S)
Thomas Sproston (Plant Biologist Inc.), E. P.Gaines
Jr., and D.J.Marx (Editors)
8. PERFORMING ORGANIZATION REPORT NO.
3. PERFORMING ORGANIZATION NAME AND ADDRESS
Vermont Yankee Nuclear Power Corporation
77 Grove Street
Rutland, Vermont 05701
10. PROGRAM ELEMENT NO.
EHE624
11. CONTRACT/GRANT NO.
Grant R804715
12. SPONSORING AGENCY NAME AND ADDRESS
EPA, Office of Research and Development
Industrial Environmental Research Laboratory
Research Triangle Park, NC 27711
13. TYPE OF REPORT AND.PERIOD COVERED
Final; 10/76 - 9/77
14. SPONSORING AGENCY CODE
EPA/600/13
15. SUPPLEMENTARY NOTES
2683.
IERL-RTP project officer is Theodore G. Brna, MD-61, 919/541-
16. ABSTRACT
The report gives results of a study of the feasibility of using low grade
(70 F) waste heat from the condenser cooling water of the Vermont Yankee Nuclear
Plant at Vernon for commercial food enhancement. The study addressed: the poss-
ible impact of laws on the use of waste heat from a nuclear plant for food production,
alternative greenhouse designs suitable for the site, and an economic and marketing
model for greenhouse crops. Using surface heat exchangers for greenhouse heating
appeared to permit compliance with the Delaney Amendment of the Food, Drug, and
Cosmetic Act when condenser cooling water is the heating medium at a nuclear
plant. The low temperature of the waste heat source suggested that supplemental
greenhouse heating will be required (a biogas facility using wastes from a dairy
herd near the plant was proposed as being economically attractive). A greenhouse
design employing heaters using methane from the proposed biogas facility and a
cropping schedule for the greenhouses was recommended. The report includes the
computer program used to determine the costs of gieenhouse production in the
Northeast.
17.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
b.lDENTIFIERS/OPEN ENDED TERMS
c. COSATI Field/Group
Pollution Greenhouses
Nuclear Power Plants
Heat Recovery
Horticulture
Condensers
Cooling Water
Comouter Proi
ipu
FRIBI
Egr
TEM
Heating
Methane
Dairies
Wastes
amming
Pollution Control
Stationary Sources
Waste Heat
Biogas
Condenser Cooling Wate
13B
18E
20M,13A
02D
13I,07A
09B
02C
13H
07C
14G
18. DISTRIBUTION STATEMENT
Unlimited
19. SECURITY CLASS (This Report}
Unclassified
21. NO. OF PAGES
156
20. SECURITY CLASS (This page)
Unclassified
•K PRICE
EPA Form 2220-1 (t-73)
148
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