RENEWABLE TECHNOLOGIES AND THEIR ROLE IN
MITIGATING GREENHOUSE GAS WARMING
Frank T. Princiotta, Director
Air Pollution Prevention and Control Division
National Risk Management Research Laboratory
U.S. Environmental Protection Agency (MD-60)
Research Triangle Park, NC 27711
Human activity has led to an increased atmospheric concentration of carbon dioxide
(C03), methane (CH4), and other gases which resist the outward flow of infrared radiation more
effectively than they impede incoming solar radiation. This imbalance yields the potential for
global warming as the atmospheric concentrations of these gases increase. For example, before
the industrial revolution, the concentration of C02 in the atmosphere was about 280 ppm, and it
is now about 360 ppm. Similarly. CH4 atmospheric concentrations have increased substantially,
and they are now more than twice what they were before the industrial revolution, currently
about 1.8 ppm. Recent data also suggest that airborne particulates have increased significantly in
the post-industrial period and have contributed to a counteracting cooling impact.
In this paper we will discuss the role that renewable and other mitigation approaches
could play in ameliorating such projected warming. In order to put this issue in context, the
following issues will be discussed:
-What is the range of projected warming?
-What is the relative importance of the various greenhouse gases?
-What are the major and projected sources of C02?
-What emission controls achieve what level of greenhouse gas warming mitigation?
-What are candidate mitigation technologies - on both the end use side and the production
side?
-Focusing on one particular renewable technology, the Hynol process, what are some of
the economic, institutional, and other barriers that hinder commercialization?
A model (Glowarm 3.0) that the author has developed to help evaluate these questions is
a spreadsheet (Lotus 1-2-3) model which calculates global concentrations and their associated
global warming contributions for all the major greenhouse gases. The model calculates
atmospheric concentrations of greenhouse gases based on projected emissions in 10-year
increments. For C02, look-up tables are used to relate the fraction of C02 remaining in the
atmosphere as a function of time after emission for two alternative C02 life cycles. For the other
gases, an inputed lifetime value is used. Average global equilibrium temperatures are calculated
by adding contributions of each gas, using lifetimes and radiative forcing functions described in
Intergovernmental Panel on Climate Change (IPCC), 1990, along with an assumed input
atmospheric sensitivity. Realized (or actual) temperature is estimated using an empirical
correlation algorithm we developed based on general-circulation model (GCM) results presented
in IPCC, 1992. This approach uses a correlation which relates the rate of equilibrium warming
-------
over the period between the target year and 19B0 to the ratio of actual to equilibrium warming.
The greater the rate of equilibrium warming, the smaller is the ratio of the actual to equilibrium
ratio. Note that it is much easier to calculate average global warming than it is to estimate
warming on a geographical or seasonal basis. Such geographical or seasonal projections require
more complex models which are subject to a much greater degree of uncertainty.
Figure 1 shows fields for the model. Note that equilibrium and transient (realized or
actual) warming can be calculated for any year (to 2100) for a variety of emission and control
scenarios, two C02 life cycles, an assumed atmospheric sensitivity to a doubling of C02
concentration, CH4 lifetime, and both sulfate cooling and CFC phaseout assumptions. Under the
same assumptions, the model output temperatures fall generally within 10% of values calculated
by other more complex models (IPCC, 1996b; NAS, 1991; Krause, 1989).
UNCERTAINTIES IMPACTING DEGREE OF WARMING EXPECTED
There are many uncertainties associated with the expected magnitude of global warming.
The following are major uncertainties which will be considered and quantified:
1. Atmospheric Sensitivity. This critical variable is generally defined as the equilibrium
temperature rise associated with a doubling of C02 concentration. GCMs are utilized by
climate modelers to forecast the impact of C02 wanning. Unfortunately, the range of
their results is wide and not converging (Dornbusch and Poterba, 1991). The IPCC
(IPCC, 1996a) has concluded this range to be between 1.5 and 4.5°C.
2. CQn Life Cycles. The Earth's carbon cycle, which involves atmospheric, terrestrial, and
oceanic mechanisms, is complex and not completely understood. Yet, in order to
estimate CO, atmospheric concentrations and subsequent warming, it is necessary to
assume a relationship between C02 remaining in the atmosphere and time after emission.
For this analysis, two C02 life cycles were utilized, one based on IPCC (1992) and the
other described by Walker and Kasting (1992). The Walker model yields longer
atmospheric lifetimes leading to higher C02 concentrations.
3. Projected Growth of CO-, Emissions Over Time for a "Business as Usual" Case
Attempting to predict the future is a risky business, at best. Yet, to scope the magnitude
of the warming issue, it is necessary to estimate emissions of greenhouse gases as far in
the future as one wishes to project warming. As we discussed and quantified in a
previous paper (Princiotta, 1994), the following are key factors which will determine a
given country's emissions of C02, the most important greenhouse gas:
current emission rate
population growth
growth of economy per capita
growth rate: energy use per economic output
growth rate: carbon emissions per energy use unit
2
-------
Since future global CO? emissions will be the sum of an individual country's emissions,
all subject to varying factors listed above, il is clear that even for "business-as-usual" (or
base case) there is a large band of uncertainty.
4. Methane Lifetime. A variety of investigators have provided a range of estimates for the
atmospheric lifetime of CH4. The longer the lifetime, the greater is CH-'s contribution to
global warming.
5. Projected Growth of Methane Emissions. There is an incomplete understanding of the
current contributions of the major anthropogenic sources of CII4. They include: landfills,
rice production, coal mines, natural gas production and distribution systems, and the
production of cattle. There is even more uncertainty regarding the likely growth of such
emissions over time as population grows, industrialization accelerates in developing
countries, and agricultural practices change.
6. Use of High Global Warming Potential Compounds (e.g., HFC-134a) to Replace
Chlorofluorocarbons (CFCs).
As the international community phases out of CFC production, due to concerns
associated with stratospheric ozone depletion, hydrofluorocarbon (HFC)-134a and other
compounds with significant greenhouse warming potential are being utilized as
replacements. The importance of the extent to which compounds such as these are
utilized will be evaluated.
7. Actual Temperature Response Versus Calculated Equilibrium Warming. GCMs often
calculate projected equilibrium warming rather than transient or actual warming.
Equilibrium warming can be defined as the temperature the Earth would approach if it
were held at a given mix of greenhouse gas concentrations over a long period of time.
Transient (also called realized or actual) temperatures are those that would actually be
experienced at a given point in time, taking into account the thermal inertia of the Earth,
especially its oceans. There is only an incomplete understanding of this thermal inertia
effect and its quantitative impact on actual warming.
8. Aerosol (Sulfate) Cooling. A recent development (IPCC, 1992) has been the availability
of evidence that emissions of sulfur dioxide (S02), other gases, and aerosols have
contributed to a significant cooling impact, counteracting greenhouse gas warming.
There is significant uncertainty over the magnitude of the direct impact of such fine
particles and even more uncertainty over their secondary impact on clouds (generally
thought to be significant and in the cooling direction).
In order to attempt to understand the impact of these variables, we have estimated
warming for five scenarios spanning what we believe are reasonable ranges of values for these
variables. For certain factors, such as atmospheric sensitivity, there is a reasonable consensus
regarding the possible range of values. For other factors, there is no such consensus. It should
be recognized that the credibility of this uncertainty analysis is only as good as the variable
3
-------
ranges assumed. Table 1 shows the assumed range of values from the "lowest" scenario, which
assumes thai all of these variables arc at values which will yield the lowest degree of warming, to
the "highest" case, which assumes those values which will yield the highest projected warming.
These can be characterized as representing best versus worst case scenarios, respectively, in the
middle is the base case which is generally consistent with the 1PCC (1992,1996b) and
represents current conventional wisdom regarding the most likely scenario.
Figure 2 graphically summarizes the results of model calculations for the five scenarios
examined. Also included in this figure is the actual warming estimated in 1980 relative to the
pre-industrial era (NAS, 1991). As indicated, the range of projected global warming varies from
significant to potentially catastrophic. We believe a more likely range of uncertainty is
represented between the low and high scenarios. The predicted warming at 2100 for these cases
is 2.1 and 5.7C0, respectively. The magnitude of these values and the difference between them
support the contention that we are dealing with an issue not only of unprecedented potential
impact, but also of monumental uncertainty. It is noteworthy that, even for the "low" scenario,
temperature increases of 2.1C° over pre-industrial values (1.6C0 over 1980 levels) are projected
by 2100. According to Vostock ice core measurements (Dornbusch and Poterba, 1991), the last
time the Earth experienced such an average temperature was 125,000 years ago.
As a basis for comparison, recently the IPCC (IPCC, 1996b) has projected warming at 2100 to
range from 1.8 to 3.0°C depending on the projected emission scenario, with the base case
wanning at 2.5°C. This warming includes the 0.5"C warming experienced from the pre-industrial
era to the current time. On the same basis, the Glowarm model calculates a base warming of
2.6°C.
It is important to note that uncertainty influences not only the predicted degree of future
warming, but also the effectiveness of a given mitigation strategy. Figure 3 illustrates this point.
Realized warming versus time is plotted for the "low," "high," and base scenarios. In addition,
two stringent mitigation cases are included. Both assume that, by the year 2000, worldwide
mitigation is imposed to decrease emissions of all greenhouse gases by 1% annually. However,
the first mitigation case assumes all of the "high" variables summarized in 'fable 1 . The second,
imposes a mitigation program assuming base (or "most likely") variables. The results are
dramatic. They show that, even with a stringent emission reduction program, if the "high" case
values are assumed, warming will be greater for all years before 2100 than for the uncontrolled
base case! Note that, if a mitigation program (1% per year reduction for this "high case") were
initiated further in the future, 2010 for example, the results would be even more dramatic. In this
case, the controlled temperature at 2100 is now about 2.4°C versus the 2.1°C for the uncontrolled
base case.
WHICH GASES ARE IMPORTANT?
Let us now examine the important greenhouse gases and their potential warming
contributions. Figure 4 shows the projected contribution by greenhouse gas over the period
1980-2050 for the base scenario. CO, and Cli, are clearly the most important contributors to
4
-------
warming, with CFCs and their substitutes, nitrous oxide (N20), and tropospheric ozone (03)1
playing small but significant roles. Noteworthy, is the projected cooling impact of aerosol
sulfates.
However, again, uncertainty is significant, this time in determining the relative
contributions of the greenhouse gases. Such uncertainties are considered in Table 2. For each
greenhouse gas, this table summarizes: atmospheric lifetime, the ratio of current to pre-industrial
atmospheric concentrations, projected contributions to realized warming, and the projected
impact of mitigating emissions. Also included is a judgment regarding the relative confidence of
the predicted warming impacts, along with major uncertainties and the major human sources.
Uncertainty is important for all gases, but especially for aerosols and tropospheric ozone.
When one considers the importance of a given greenhouse gas, it is informative to
evaluate wanning prevented for a given mitigation scenario. Figure 5 shows results of model
calculations for the period 1980-2050 comparing equilibrium base scenario warming to warming
prevented assuming a stringent mitigation program, in this case, a 1% annual reduction in
emissions is assumed for each gas (or its precursor), exclusive of sulfates, starting in the year
2000. The main result here is that a higher fraction of their base warming can be mitigated for
the short-lived gases such as CI I4 and 03. For example, whereas less than half of C02's base
warming is mitigated in this case, about three-quarters of Clip's base warming is mitigated.
When viewed from a mitigation (or warming prevented) viewpoint, CH4 is about half as
important as CO,; whereas, from an emission viewpoint, it is less than a third as important.
Figure 6 shows additional model results to help shed light on this point. In this case, the
effect of annual mitigation rate (starting in 2000) on equilibrium warming mitigated by gas is
illustrated. An interesting observation that can be made is that a stringent 2% per year mitigation
program for CH4 could have almost as much benefit by the year 2050 as capping (0% growth)
CO, emissions. Of course, such conclusions are subject to the uncertainties previously
discussed.
WHICH COUNTRIES ARE MAJOR CONTRIBUTORS TO EMISSION OF
GREENHOUSE GASES? WHAT ARE LIKELY TRENDS?
It is useful to look at recent histories of CO, emissions for key countries. Figure 7
derived from NAS, 1991, illustrates growth in C02 emissions from 12 key countries between
1960 and 1988. As indicated, the U.S., USSR (now Russia, Ukraine, and other independent
countries), and China are by far the major sources of C02. However, when one considers the
recent (1980-1988) growth rate, China and India are especially significant since this portends
'This value assumes volatile organic compound (VOC), nitrogen oxide (N02), and carbon
monoxide (CO) precursors contribute to 03 formation. However, the small component of 03
wanning associated with CH4 emissions is included in the CII4 value.
C
.j
-------
future contributions to CO- emissions. Table 3 summarizes 1988 C03 data (NAS. 1991) for key
countries listed in order of overall emissions, per capita emissions, and per gross national product
(GNP) emissions. Although, the U.S. leads the world in overall and per capita emissions, China
easily has the largest per emissions GNP.
In order to provide insight into the various sectors contributing to 1990 C'02 emissions for
key countries, Figure 8 was generated based on Oak Ridge National Laboratory (ORNL)
calculated data (Bowden, et al, 1993). This figure illustrates that each country has a distinctive
mix of activities yielding C02 emissions. In the case of the U.S., coal combustion (for electricity
and steam), petroleum for transportation, and natural gas combustion (primarily for power
generation and space heating) are the three most critical contributors. The pattern is similar in
the former Soviet Union with the major difference in the automobile sector; much less C02 is
generated by a much smaller fleet of vehicles. In China, coal combustion is the dominant source
of C02 emissions, helping to explain why China's C02 unit of GNP is so high; coal is by far the
most C02-rich fuel source per unit of useful output energy. Germany, the fourth most important
source of CO,, is also dominated by coal use: in their case, brown coal (lignite) is indigenous to
their country. Japan, with few indigenous fossil fuel resources, is heavily dependent on imported
coal and residual oil for power generation. It is interesting to note that India, the second most
populous country in the world and likely a major future contributor, has a pattern similar to
China, with steam coal the dominant source.
We have already discussed the uncertainties associated with future emissions of C02.
Such emissions will depend on country-specific factors: population growth, rate of
industrialization, energy use per economic output, and carbon use per energy utilized. Table 4
(Princiotta, 1994) shows a projection of growth of these factors for the developed (Organization
for Economic Cooperation and Development—OECD) and relatively undeveloped Asian
countries for the period 1990-2025. This projection is derived from information presented in
IPCC, 1992. For the OECD countries, the key driver yielding increased C02 emissions is
expected to be economic growth, whereas population growth is projected to be quite modest. For
the Asian countries, the key driver is likely to be economic growth, with population growth also
significant. For both regions, in the absence of a C02 mitigation program, energy efficiency
gains and a decrease in carbon-intensive energy use are projected to be modest over this time
period.
It is useful to examine the likely results of these drivers on projected emissions of CO,
from selected countries. Figures 9 and 10 show such a projection assuming economic,
population, and energy use trends summarized in IPCC, 1992. Projections for the years 2030
and 2100 are combined with actual C02 emission data (NAS, 1991) from the 1960-1988 time
period. These graphics show that the Asian countries, especially China and India, driven by high
projected economic growth and large populations, will be dominant C02 emitters by the middle
of the next century.
6
-------
MITIGATION: HOW MUCH AND WHEN TO START?
Figure 11 illustrates the projected results of two hypothetical mitigation scenarios
compared to the base case which assumes current expectations for greenhouse gas emissions. If
emissions were held constant at year 2000 levels, the rate of projected warming could be slowed
substantially; although significant warming would continue for the foreseeable future. However,
if emissions for all greenhouse gases were reduced 1% annually, post-1980 wanning could be
stabilized below about 1° C by the year 2100. Therefore, in order to mitigate warming over the
long term, it will be necessary to reduce greenhouse gas emissions substantially over time. This
will be a difficult goal, considering projected rates of economic and population growth which are
key drivers for greenhouse gas emissions. Figure 12 illustrates this point by showing on one
graphic, projected economic activity, population, base case C02 emissions, and mitigated CO-,
emissions unitized at 1990.
Figure 13 illustrates the impact of the year control starts on realized warming projected
in 2050 for two mitigation scenarios (1% of annual control and an emission cap). As indicated,
early emission control allows for a larger degree of climate stabilization. These results suggest
that there can be major stabilization benefits for early initiation of mitigation.
MITIGATION: WHICH SOURCESAVHICII TECHNOLOGIES?
It is useful to examine recent C02 energy use patterns in order to ascertain which sectors
and fuels are significant C02 emitters and candidates for mitigation. Table 5 (adapted from
IPCC, 1996a) illustrates that all major energy categories are important emitters of C02 so that all
major energy sectors will require major improvements in end use efficiency and, in the longer
term, migration away from fossil fuels if stabilization efforts are to be successful.
Since it is clear that fossil fuel use is the key driver for greenhouse gas warming, a
relevant question is: how much fossil fuel is available and how long will it last?
Table 6 adapted from IPPC, 1996a, and augmented-by the author, summarizes the
prevailing view on this subject. Basically, oil appears to be the least abundant fossil fuel with
reserves plus most likely discovered conventional oil estimated to be 8500 EJ. Such an amount
would be depleted by about 2035, if oil use rate were to increase by 1.5% per year. If
unconventional reserves which, include heavy oil, oil shale, and oil tar deposits, are included, the
availability of oil could be extended to about 2080, again assuming 1.5% increase in use per year
until depletion. For conventional gas, the reserves plus expected discovered resources are
estimated to be 9200 EJ . If gas use rate would increase 1.5% annually, these resources would be
depleted by 2065. If unconventional gas sources are considered, gas resources wouldn't be
depicted before about 2135 under the assumptions described above. As indicated, known
reserves of coal are much larger, with depletion estimated at 2195 under the 1.5% annual growth
assumption. Taken together all fossil fuel resources appear to be sufficient to last until about
2150. From a greenhouse warming viewpoint, gas is the most desirable fossil fuel since it has a
7
-------
high hydrogen to carbon ratio and generates substantially lower quantities of C07 than do oil and
coal.
A reasonable scenario, then, is that sometime during the first half of the next century
conventional sources of oil and later gas will become scarce and more expensive.
Unconventional sources will likely become available but at substantially higher prices than for
more easily extracted conventional sources. At the same time, depending on economic
conditions, political policies, and technology availability, coal and/or alternative sources of
energy, (e.g.. biomass, solar) will fill the gap left by the depletion of relatively inexpensive oil
and gas resources.
Since fossil fuels are the key driver for greenhouse gas warming, and their resources are
limited, especially for oil, a key question is what renewable resources are potentially available to
displace oil, gas and coal. Table 7, adapted from 1PCC, 1996a, and augmented by the author,
shows the potential renewable resource available in the 2020-2025 time frame and for the longer
term. Also included is information estimating the fraction of total projected global energy use
that these resources could supply. As can be seen, in the nearer term horizon (2020-2025) only
biomass, hydro, and solar (in that order) appear to be available in sufficient quantities to displace
a major component of fossil fuel use. In the longer term only solar and biomass appear to offer
the potential for wide scale displacement.
Any successful mitigation program dealing with the critical energy sector must
aggressively deal with the two fundamental components of the energy cycle: end use efficiency
and production. Tables 8 and 9, adapted from NAS, 1991, list and briefly summarize candidate
mitigation options for the end use and production sectors, respectively. Since electricity
production and use, residential, commercial and industrial combustion, and transportation energy
use are all major current and projected generators of C02, all these sectors must make
fundamental end use and production improvements if a stabilization program is to be successful.
The author is convinced that meaningful mitigation can be achieved only with an
aggressive program aimed at using less energy in all sectors in the near term, supplemented by
new technologies capable of displacing fossil fuels in the longer term. This contention is
supported by one of the most detailed assessments of its kind (EPA, 1990), in which a multitude
of options were evaluated for their quantitative potential in mitigating greenhouse warming in the
2050 and 2100 time frame. Table 10 is adapted from that study and compares the mitigation
potential of those options which can reduce emissions of C02. As can be seen, both end use and
production strategies can be effective in mitigating greenhouse gas warming in these time
frames. Of particular potential importance are end use efficiency in transportation and stationary
source combustion systems, and in the production side via extensive displacement of fossil fuels
by biomass. Also, potentially significant would be a forest sequestration strategy to reverse the
current trend of deforestation with wide-scale reforestation.
When one considers the potential problem posed by long term fossil fuel use from a
greenhouse wanning viewpoint, and the likely depletion of cheap fossil fuels, especially oil and
8
-------
gas, within a few generations, one might expect a massive worldwide effort to develop renewable
alternatives and energy conservation technologies. This is not the current situation. Table 11
(IPCC, 1996a) summarizes energy research in the IEA countries (industrialized) Com 1983 to
1994. As can be seen, R&D expenditures have been generally decreasing during this period,
especially when calculated as a fraction of Gross Domestic Product (GDP). Also, by far the
largest component of such research has been focused on nuclear fission, a commercial
technology with many economic and political problems not likely solved with research. It is
interesting to note that the U.S. military research budget alone in the post cold war era is about
3.5 times greater than the combined energy research for all the IEA countries!
Focus on Hvnol Process Utilizing Biomass and Methane to Yield Transportation Fuels
In order to consider some of the real world difficulties of developing and
commercializing a potentially significant C02 mitigation technology, we will discuss the Hynol
process. This process, which was innovated at DoE's Brookhaven National Laboratory, has been
under development via EPA sponsorship with contributions from the California Energy
Commission and DoD's Strategic Environment Research and Development Program (SERDP).
Bench scale work over a 4 year period has been performed at Brookhaven and at EPA's
Research Triangle Park, NC, facility to provide fundamental design information. This process
could be used to provide fuel to dedicated light and heavy duty vehicles designed for methanol
fuel as well as fuel-cell powered vehicles. Figure 14 is a schematic of the process.
Analysis of technological options for converting biomass to liquid fuels showed that
methanol, produced by the Hynol process, could displace more gasoline at lower cost—and with
greater effect on the net C02 emissions—than other process options (Borgwardt, 1997). Methanol
from the Hynol process cost is estimated at $0.48/gallon ($0.13/liter) for a 7870 tonne/day plant
with 15.45% Capital Recovery factor, $61/tonne biomass cost, and natural gas at $2.50/106 Btu
($1.055/GJ). It is currently estimated to be competitive with current equivalent gasoline prices in
conventional vehicles.
A patent for the Hynol process was issued on September 6, 1994. A 50 lb/hour (23
kg/hour) pilot test facility has been constructed for testing the critical gasifier and will commence
operation soon. University of California, Riverside, has the lead research role via a cooperative
agreement with EPA. Figure 15 illustrates the projected cost of Hynol methanol as a function of
natural gas price.
The following are the author's observations and opinions regarding the difficulty of
developing and ultimately commercializing such a process under the current economic and
political situation.
Despite the potential of a process such as Hynol to displace oil and/or to reduce
greenhouse gas emissions, there is no commercial incentive to develop biofuels as long as
their cost exceeds, or even is equivalent to, that of fossil fuels. Situations where biomass
9
-------
can compete economically with fossil fuels arc very few and have insignificant potential
for affecting global greenhouse gas emissions.
If greenhouse gas emissions is the only factor justifying hiofuel utilization, development
of biofuel technology is improbable without support by the government for the R&D that
is necessary to demonstrate the technology and for providing incentives for renewable
energy use.
In the U.S., despite a robust economy, funding for renewable energy R&D is constrained
to a modest level because of concerns about buduet deficits and the absence of anv
imminent energy or environmental emergency. In the case of Hynol, it has been difficult
to convince federal and private research sponsors to provide the resources for
comprehensive testing of an integrated pilot of the process. The current pilot program is
limited to gasificr evaluation.
As long as petroleum is one of the lowest-cost sources of energy, and there is no global
commitment to greenhouse gas reduction, only market forces will determine the fate of
any effort to develop a biofucl alternative. The current basic cost of petroleum
production is so low that it could undercut any attempt to start a major biofuel industry.
If either petroleum displacement or greenhouse gas reduction is to be appreciably affected
by biofuel. a very large plant must be considered, like 9000 lonnes/day of biomass feed.
This is simply a matter of the number of plants that would be required to displace a
significant portion of the current consumption of fossil fuel. The logistics of producing
and delivering 9000 tonnes of biomass per day is formidable, given the land area,
transport system, storage, etc., that are required. Capital investment in the plant alone
would be over Slbillion (IxlO9); raising such an amount would be quite difficult unless
risks were very low and potential profits high.
Convincing landowners of the merits of investing and establishing dedicated energy
plantations on a large scale, even before a conversion plant is built, will be difficult.
Building a conversion plant before the energy crops are in production, will also be a risk.
Government guarantees would likely be necessary.
Even at 9000 tonnes/day, leveraging of the yield of liquid fuel from biomass will be
necessary for practical consideration, given the amount of fuel needed, the number of
plants required, and the production cost. Ilynol methanol provides a means of such
leveraging by use of natural gas as cofeedstock. Further leveraging will be achievable
when high efficiency fuel cell vehicles become commercialized, probably about the same
time as a viable biofuel industry could be established.
Energy companies have billions of dollars invested in infrastructure for the petroleum
fuel cycle; therefore, there is a tremendous amount of inertia to make fundamental
changes in this area. Energy companies have a considerable vested interest in the status
10
-------
quo, considering this investment.
As a new fuel to be potentially used in unprecedented quantities and in locations all"
around the country, the following issues will have to be evaluated and resolved before
such widescale use is practical: (1) potential toxicity; (2) potential for groundwater
contamination; and (3) corrosivcness to vehicle components.
SUMMARY AND CONCLUSIONS
A spreadsheet model has been utilized to calculate both equilibrium and realized
greenhouse wanning as a function of key variables including: greenhouse
gas emission growth rates, C02 life cycles, CH4 lifetime, current aerosol cooling, and
CFG phaseoui assumptions.
Model calculations lor the three most credible cases, assuming a varying range of
assumptions, yield projected warming at 2100 from a substantial 2.1C" to a potentially
catastrophic 5.7C". The most likely case yields 2.6C0 projected warming from pre-
industrial values: such warming is consistent with the most recent IPCC (IPCC, 1996b).
Such uncertainty also impacts the estimates of the effectiveness of a mitigation program.
Model results suggest that, even assuming a stringent mitigation program, if key
uncertainties all align toward maximum greenhouse warming, warming will be greater
than it would be for a business-as-usual case assuming the mid-range of the key variables
contributing to uncertainty.
Aerosol/sulfate cooling is an important phenomenon, with recent data suggesting cooling
comparable to the warming associated with CH4, the second most important greenhouse
gas. Again, uncertainty in current and projected cooling is substantial.
C02 is the largest potential contributor of the greenhouse gases, with CH,, the second
most important contributor. Warming associated with tropospheric ozone could be
important, but the underlying science allowing a quantitative judgment is weak.
Mitigating CH4 emissions can achieve substantial benefits, in the near term, in light of its
relatively short atmospheric lifetime. In fact, a 2% per year CH4 mitigation program can
be almost as effective as placing a cap on C02 emissions, assuming mitigation started in
2000 and the target year is 2050.
The United States, the former Soviet Union, China, Germany, and Japan are the largest
emitters of C02 (in rank order). Each has a distinctive profile with regard to
contributions per fuel-use sector. Developing countries in Asia, such as China and India,
are expected to have exponential growth in greenhouse gas emissions, driven primarily
by projected economic growth and dependence on coal as a major fossil fuel.
Model analysis shows that the time mitigation is initiated has an important impact on the
-------
degree of mitigation achievable. For example, a program to cap (hold constant)
greenhouse gas emissions can be equally effective as a more stringent mitigation program
initiated 10 years later.
Mitigation of greenhouse gas emissions will be a major challenge, since it may be
necessary to dramatically decrease emissions over time. This would run counter to very
strong trends toward progressively increasing emissions, driven by projected economic
and population growth and widescale use of coal. Such mitigation may require major
enhancements in end use efficiency in the short term and a major transition to renewables
in the longer term.
Fossil fuels are a finite source of energy. Oil and gas are projected to become scarcer and
much more expensive during the middle portion of the next century. Among the
renewable energy resources, only biomass and solar appear to have the potential for large
scale fossil fuel displacement. Despite this, research on renewable technologies is at a
constrained level, and, in the author's view, unlikely to provide technology capable of
displacing large quantities of fossil fuel at competitive costs anytime in the foreseeable
future.
The Hynol process is a potentially attractive technology generating methanol (or
hydrogen) for the transportation sector. However, as for other renewable technologies, a
host of political, economic, and policy factors inhibit commercialization.
12
-------
References
Borgwardt, R.H. "Biomass and Natural Gas as Co-Feedstocks for Production of Fuel for Fuel-
Cell Vehicles," Biomass and Bioenergy, Vol. 12, No. 5, pp. 333-345, 1997.
Bowden, T.A., et al. "CDIAC Catalog of Numeric Data Packages and Computer Model
Packages." Carbon Dioxide Information Analysis Center. Oak Ridge National Laboratory, Oak
Ridge, TO. Document No. ORNL/CD1AC-62" May 1993.
Dornbusch, R., and Poterba, J.M. "Global Warming Economic Policy Responses." The MIT
Press, Cambridge, MA, 1991.
Environmental Protection Agency. "Policy Options for Stabilizing Global Climate," Report to
Congress, 21P-2003.1, U.S. EPA, Office of Policy, Planning and Evaluation, Washington, DC,
December 1990.
Intergovernmental Panel on Climate Change (IPCC), "Scientific Assessment of Climate
Change," Cambridge, UK, June 1990.
Intergovernmental Panel on Climate Change (IPCC), "Climate Change 1992 - The
Supplementary Report to the IPCC Scientific Assessment," Cambridge, UK, 1992.
Intergovernmental Panel on Climate Change (IPCC), "Technologies, Policies and Measures for
Mitigating Climate Change," Cambridge, UK, 1996a.
Intergovernmental Panel on Climate Change (IPCC), "Climate Change 1995, The Science of
Climate Change," Cambridge, UK, 1996b.
Krause, F. "Energy Policy in the Greenhouse." International Project for Sustainable Energy
Paths (IPSEP), El Cerrito, CA, 1989.
National Academy of Sciences (NAS). "Policy Implications of Greenhouse Warming." National
Academy Press, Washington, DC, 1991.
Princiotta, F.T. "Greenhouse Warming: The Mitigation Challenge." In Proceedings: The 1992
Greenhouse Gas Emissions and Mitigation Research Symposium, EPA-600/R-94-008 (NTIS
PB94-132180), U.S. EPA, Air and Energy Engineering Research Laboratory, Research Triangle
Park, NC, January 1994.
Walker, J.C.G., and Kasting, J.F. "Effects of Fuel and Forest Conservation on Future Level of
Atmospheric Carbon Dioxide." Paleoclimatol., Palaeocol, (Global and Planetary Change
Section). 97 (1992) pp. 151-189. Elsevier Science Publishers.
13
-------
Table 1: Five Scenarios Impacting Degree of Global Warming
Variable Impacts mPredicteci Warnim
Range of impacts—>Gmi
ter Warming
Lowest
Low
Most.Ukaty
High
Highest
Atmospheric Sensitivity
1.5
2
2.5
3.5
4.5
C02 Life Cycle Model
IPCC
IPCC
IPCC
Kasten
Kasten
C02 Growth Rate:1990-2030
1.4%
1.6%
1.85%
2.00%
2.2%
Co2 Growth Rate:2030-2100
0.5%
0.65%
0.78%
1.85%
2.2%
Methane Lifetime, years
7
8
11
12
13
CH4 Growth Rate:1990-2030 / 2030-2100
0.67%/0.32%
0.77%/.52%
1.17%/.82%
1.27%/.92%
1.37%/1.02%
Penetration of HFC-134a
15%
25%
35%
45%
55%
Actual/Equil. Temp.Ratio @ 0.35 C degree/yr
0.3
0.4
0.505
0.6
0.7
Current Sulfate Cooling, degree C
-2.5
-2
-1.65
-1
-0.1
Sulfate Coding Emission Ratio Exponent
1
0.9
0.8
0.7
0.6
OUTPUT Calculations,Deqree C.
Equilibrium Temperature @ 2050
0.5
1.2
2.3
5.1
7.8
Realized Temperature @ 2050
0.5
0.9
1.2
2.6
4.4
Equilibrium Temperature @ 2100
1.1
2.4
4.3
10.3
15.9
Realized Temperature @ 2100
0.9
1.7
22
5.2
9.1
-------
Table 2: Greenhouse Gases - What is Known and What is Not
CHARACTERISTIC
CARBON DIOXIDE
METHANE
AEROSOLS
HFC-134a
TROPO. OZONE
N20
1. Atmospheric Lifetime (yrs)
50-100
10-12.5
«1
10
«i
150
2. Current Concentration/
1.26
2.15
Uncertain
New CFC Substitute
>i. But Poor Data
1.08
P re-Industrial Cortcentration
3. Projected Reillzed Warming/
By Gas at the Year 2100
~1.8
~0.5
-0.8
~0.2
~0.1
~0.1
Most likely Case: Total Warming ¦ 7J2
Ind. Indirect Effects
(Excludes CH4 source)
4. Impact of 1% /Yf MttSgaBon:
60%
31%
4%
4%
Control starts at 2000, the Impact at 2050:
Calculated as % of total mitigation
5. Confidence In Warming Calculations
Fair/Good
Fair
Poor
Good
Poor
Fair
for Items 3. and 4. Above
8. Major Uncertainties
Carbon Cycle Influence on
1. Quantification of Natural and
1. Current Extent of Cooling
Extent ta Which WIS
1. Atmospheric Chemistry
Atmospheric Concentration
CO2 Atmospheric Lifetime
Human Sources and Sinks
2. Relationship of Emissions
Substitute for CFCs
Models Insufficient
Rising Fatter Than Known
2. Explanation Needed for Decelerat-
to Atm. Aerosols
2. Data on Tropo. Ozone
Sources/Sinks Predict
ing Growth In Atm. Concentrations
3. Impact on Cloud Formation
Trends Poor
3, Emission Data for NOx,
Hydrocarbons and CO
Precursors Poor
7. Major Human Sources
Fuel Combustion
Coal Mining
Fossil Fuel Combustion
Refrigeration Cycles
Mobile Sources: VOCs, NOx,
Biomass Burning
• Electric Power
Natural Gas and Oil Production and
Biomass Combustion
•
and CO
Adlpic Acid and HNO J Prod.'
-Mobile Sources
Transportation
Stationary Combustion:
Mobile Sources
- Industrial Deforestation
Landfills
NOx and CO
Farming
Btca Paddles
Biomass Burning: CO and
Stationary Source
Ruminants
VOCs
Combustion
Biomass Burning & Decomposition
-------
Table 3: 1988 C02 Data for Key Countries
(Note: 1 ton * 0.9078 metric ton )
Cm Emissioiis-1988
CQ2 per capita:
C02iicrGNP
-
(Million of Tons)
(tons per person)
(MtC02 per 51000 GNP)
United States
4804
United States
19
China
6.0
USSR
3982
Canada
17
South Africa
3.6
China
2236
Czechoslovakia
15
Romania
_2.8
Germany
997
Australia
15
Poland
2.7
Japan
989
USSR
14
India
2.5
India
601
Germany
13
Czechoslovakia
1.9
United Kingdom
559
Poland
12
Mexico
1.7
Poland
459
United Kingdom
10
USSR
1.5
Canada
438
Romania
10
Korea
1.2
Italy
360
South Africa
8
Canada
1.0
France
320
Japan
8
United States
1.0
Mexico
307
Italy
6
Australia
1.0
South Africa
284
France
6
United Kingdom
0.8
Australia
241
Korea
5
Germany
0.7
Czechoslovakia
234
Spain
5
Brazil
0.6
Romania
221
Mexico
4
Spain
0.6
Korea
205
China
2
Italy
0.4
Brazil
202
Brazil
2
Japan
0.3
SDain
188
India
1
France
0.3 "
-------
Table 4: Assumed Annual Growth Factors Influencing C02
Emissions (1990 - 2025)
(Derived from IPCC, 1992)
FACTOR
OECD
ASIA
Growth of Economy Per Capita
2.2%
3.5%
Population Growth Rate
0.3%
1.5%
Growth Rate: Energy Use Per Economic Output
-1.1%
-0.8%
Growth Rate: Carbon Emissions Per Energy
Use Unit
-0.7%
-0.3%
Annual C02 Growth Rate
(Sum of above factors)
+0.7%
+3.9%
17
-------
Table 5:1990 Global Energy Use and C02 Emissions from Energy Sources
Carbon expressed In Gt C; Energy as EJ
Energy C02
Used Emitted
Electric Generation 96 1.3
Direct Use of Fuels by Sector
Res'id./Comm./lnst. 47 0.9
Industry 68 1.4
Transportation 51 0.9
TOTAL 262 4.5
Demand Side
Resid./Comm./lnst. 86 1.4
Industry 123 2.1
Transportation 52 li)
TOTAL 262 4.5
By Source
Solids 77 1.9
Liquids 90 1.7
Gases 61 0.9
Other M &Q
TOTAL 262 4.5
-------
Table 6: Global FossilEnergy Reserves and Resources,
In EJ
Consumption
1860-1990 1990
Reserves
Identified
Conventional Resources
Remaining to
Be Discovered
at Probability
95% 50% 5%
Unconventional
Resources
Recoverable
W/Techno-
Currently Logical
Recoverable Progress
Resource
Base"
Year Resource
Is Depleted
(at 1.5% annual
growth rate)
Oil
Conventional
Unconventional
3343
128
6000
7100
1800 2500 5500
9000
8500
16100
2035
2080
Gas
Conventional
Unconventional
1703
71
4800
6900
2700 4400 10900
2200
17800
9200
26900
2065
2135
Coal
5203
91
25200
13900
86400
125500
2195
Total
10249
290
50000
>4500 >6900 >16400
>16100
>113200
>186200
2150
Notes: All totals have been rounded: - = negligible amounts: blanks = data not available
* Resource base is the sum of reserves and resources. Conventional resources remaining to be discovered at probability of 50% are included for oil and gas
-------
Table 7: Global Renewal Energy Potentials by 2020-2025, and Maximum
Technical Potentials in EJ Thermal Equivalent *
Consumption
1860-1990 1990
Potential by
2020-20256
Fraction
Global Energy
By 2050 c
Long-Term
Technical
Potentials'1
Fraction
Global Energy
by 2100«
Hydro
560 21
35-55
5-8%
>130
>9%
Geothermal
>1
4
0.5%
>20
>1%
Wind
-
7-10
1-1.5%
>130
>9%
Ocean
-
2
0.2%
>20
>10%
Solar
-
16-22
2-3%
>2600
100%
Biomass
1150 55
72-137
9-19%
>1300
>87%
Total
1750 76
130-230
18-32%
>4200
100%
Notes: All totals have been rounded; - =negligible amounts; blanks = data not available
* All estimates have been converted into thermal equivalent with an average factor of 38.5%.
11 It represents renewable potentials by 2020-2025, in scenarios with assumed policies for enhanced exploitation of renewable potentials.
c Based on potential by 2020-2025 and assuming 709 EJ utilized in 2050.
a Long-term potentials are based on the IPCC Working Group II. This evaluation is intended to correspond to the concept of fossil energy resources,
conventional and unconventional.
' Based on long-term potentials by 2100, assumed 1492 EJ in 2100.
-------
Table 8: Brief Descriptions of End Use Mitigation Options
For the United States (NAS, 1991)
END USE: RESIDENTIAL AND COMMERCIAL ENERGY MANAGEMENT
Electricity Efficiency Measures
Residential Lighting
Water Heating
Commercial Lighting
Commercial Cooling
Commercial Refrigeration
Residential Appliance
Residential Space Heating
Commercial and Industrial
Space Heating
Commercial Ventilation
Oil and Gas Efficiency
Reduce lighting energy consumption by 50% in all U.S. residences through replacement
of incandescent lighting with compact fluorescents.
Improve efficiency by 40 to 70% through efficient tanks, increased insulation, low-flow
devices, and alternative water heating systems.
Reduce lighting energy consumption by 30 to 60% by replacing 100% of commercial
light fixtures with compact fluorescent lighting, reflectors, occupancy sensors, and
day lighting.
Use improved heat pumps, chillers, window treatments, and other measures to reduce
commercial cooling energy use by 30 to 70%.
Improve efficiency 20 to 40% through improved compressors, air barriers and food case
enclosures, and other measures.
Improve efficiency of refrigeration and dishwashers by 10 to 30% through
implementation of new appliance standards for refrigeration, and use of no-heat drying
cycles in dishwashers.
Reduce energy consumption by 40 to 60% through improved and increased insulation,
window glazing, and weather stripping along with increased use of heal pumps
and solar heating.
Reduce energy consumption by 20 to 30% using measures similar to those for the
residential sector.
Improve efficiency 30 to 50% through improved distribution systems, energy-efficient
motors, and various other measures.
Reduce residential and commercial building fossil fuel energy use by 50% through
improved efficiency measures similar to the ones listed under electricity
efficiency.
(continued)
-------
Tabic 8 (continued)
Fuel Switching Improve overall efficiency by 60 to 70% through switching 10% of building electricity
use from resistance heat to natural gas heating.
END USE: INDUSTRIAL ENERGY MANAGEMENT
Cogeneration Replace existing industrial energy systems with an additional 25,000 MW of co-
generation plants to produce heat and power simultaneously.
Electricity Efficiency Improve electricity efficiency up to 30% through use of more efficient motors, electrical
drive systems, lighting, and industrial process modification.
Fuel Efficiency Reduce fuel consumption up to 30% by improving energy management, waste heat
recovery, boiler modifications, and other industrial process enhancements.
New Process Technology Increase recycling and reduce energy consumption primarily in the primary metals, pulp
and paper, chemicals, and petroleum refining industries through new, less energy
intensive process innovations.
END USE: TRANSPORTATION ENERGY MANAGEMENT (Note: 1 mpg = 0.42 km/liter)
Vehicle Efficiency
Light Vehicles
Heavy Trucks
Aircraft
Transportation Demand
Use technology to improve on-road fuel economy to 25 mpg with no changes in the
existing fleet.
Improve on-road fuel economy to 36 mpg with measures that require changes in the
existing fleet such as downsizing.
Use measures similar to those for light vehicles to improve heavy truck efficiency up to
31 mpg.
Implement improved fanjet and other technologies to improve fuel efficiency by 20% to
130 to 140 seat-miles per gallon.
Reduce solo commuting by eliminating 25 % of the employer-provided parking spaces
and management placing a tax on the remaining spaces to reduce solo commuting by an
additional 25 %.
-------
Table 9: Brief Descriptions of Production-side Mitigation Options
for the United States (NAS, 1991)
(Note 1 Quad = 1.055 x 1018 J)
ALTERNATIVE FUELS FOR
TRANSPORTATION
Methanol from Biomass
Hydrogen from Nonfossil Fuels
ELECTRICITY AND FUEL SUPPLY
Heat Rate Improvements
Advanced Coal
Natural Gas
Nuclear
Hydroelectric
Geothermal
Biomass
Solar Photovoltaics
Solar Thermal
Wind
C02 Collection and Disposal
Replace all existing gasoline engine vehicles with those that use methanol produced from
biomass
Replace gasoline with hydrogen created from electricity generated from nonfossil fuel
sources such as nuclear and solar energy directly in transportation vehicles.
Improve heat rates (efficiency) of existing plants by up to 4% through improved plant
operation and maintenance.
Improve overall thermal efficiency of coal plants by 10% through use of integrated
gasification combined cycle, pressurized fluidized-bed, and advanced pulverized coal
combustion systems.
Replace all existing fossil-fuel-fired plants with gas turbine combined cycle systems to
both improve thermal efficiency of current natural gas combustion systems, and
replace fossil fuels such as coal and oil that generate more C02 than natural gas.
Replace all existing fossil-fuel-fired plants with nuclear power plants such as advanced
light-water reactors.
Replace fossil-fuel-fired plants with remaining hydroelectric generation capability of 2
quads.
Replace fossil-fuel-fired plants with remaining geothermal generation potential of 3.5
quads.
Replace fossil-fuel-fired plants with biomass generation potential of 2.4 quads.
Replace fossil-fuel-fired plants with solar photovoltaic generation potential of 2.5 quads.
Replace fossil-fuel-fired plants with solar thermal generation potential of 2.6 quads.
Replace fossil-fuel plants with wind generation potential of 5.3 quads.
Collect and dispose of all C02 generated by fossil-fuel-fired plants into the deep ocean or
depleted gas and oil fields.
-------
Table 10: Selected C02 Emission Global Mitigation Policy Strategies:
Decrease in Projected Warming (Equilibrium)
Relative to Base Case (Adapted from EPA, 1990)
Strategy
Assumptions
Potential Emission
Reductions
2050 2100
Comments
End Use Strategies
Improved Transportation
Efficiency
See Footnote a
6%
9%
Recent trends in US moving in opposite direction, many
low mpg vans, light trucks replacing autos
Residential, Commercial
Industrial Efficiency Gains
See Footnote b
9%
15%
Such reductions would require major marketing campaign,
carbon taxes and other economic incentives
Production Strategies
More Nuclear Power Use
(Electricity Production)
See Footnote c
2%
4%
Such increased use would need to be accepted by public.
Marketing incentives as well as assumed cost reduction
needed
Solar Technologies
(Electricity Production)
See Footnote d
2%
4%
Breakthrough in technology would be necessary for such
penetration
Natural Gas Incentives
(Electricity Production)
See Footnote e
<1%
<1%
Natural gas generates about half the C02 per output relative
to coal. Availability of natural gas limits option.
Commercialized Biomass
(Transportation & Stationary Source)
See Footnote f
8%
12%
Largest potential impact of renewable technologies;
feasibility dependent on large areas dedicated to energy
crops and available production technology and end use of
infrastructure
Sequestration Strategies
Reforestation
See Footnote g
7%
5%
Would require a massive turn around toward net forest gain
relative to current rapid deforestation
a.The average efficiency of cars and light tracks in the U.S. reaches 30 mpg (7.8 liters/100 km) by 2000, new cars achieve 40 mpg (5.9 liters/100 km). Global
fleet-average automobile efficiency reaches 43 mpg by 2025.
b.The rates of energy efficiency improvements in the residential, commercial, and industrial sectors are increased about 0.3-0.8 percentage points annually from
1985 to 2025 compared to the base case and about 0.2-0.3 percentage points annually from 2025 to 2100.
c. Assumes that technological improvements in the design of nuclear powerplants reduce costs by about 0.6 cents/kWh by 2050. In the base case nuclear costs in
1985 were assumed to be 6 to 10 cents/kWh (1988 $).
d. Assumes that low-cost solar technology is available by 2025 at costs as low as 6.0 cents/kWh. In the base case these costs approached 8.5 cents/kWh but
these levels were not achieved until after 2050.
e. Assumes that economic incentives to use gas for electricity generation increase gas share by 5% in 2000 and 10% in 2025.
f. Assumes the cost of producing and converting biomass to modern fuels reaches S4.25/GJ (1988 $) for gas and S6.00/GJ (1988 $) for liquids. The maximum
amount of liquid or gaseous fuel available from biomass (i.e., after conversion losses) is 205 EJ.
g. The terrestrial biosphere becomes a net sink for carbon by 2000 through a rapid reduction in deforestation and a linear increase in the area of reforested land
and biomass plantation. Net C02 uptake by 2025 is 0.7 Pg C. In the base case, the rate of deforestation continues to increase very gradually, reaching 15 Mha'vr
in 2097, and no reforestation occurs.
-------
Table 11: Total Reported IEA Government R&DBudgets (Columns 1-7; USS Billion (10*) at 1994
Prices and Exchange Rates) and GDP (Column 8; U.S.S Trillion (1012) at 1993 Prices)
N>
(1)
(2)
(3)
(4)
(5)
(6)
(7)
(8)
(9)
Fossil
Nuclear
Nuclear
Energy
Renewable
%of
Year
Energy
Fission
Fusion
Conservation
Energy
Other
Total
GDP
GDP
1983
1.70
6.38
1.43
0.79
1.05
1.08
12.40
10.68
0.12
1984
1.60
6.12
1.44
0.70
1.02
0.99
11.88
11.20
0.11
1985
1.51
6.26
1.42
0.70
0.85
1.04
11.77
11.58
0.10
1986
1.51
5.72
1.31
0.59
0.66
0.94
10.74
11.90
0.09
1987
1.37
4.36
1.23
0.65
0.62
1.04
9.27
12.29
0.08
1988
1.46
3.64
1.13
0.53
0.62
1.19
8.58
12.82
0.07
1989
1.30
4.42
1.07
0.45
0.57
1.33
9.13
13.23
0.07
1990
1.75
4.48
1.09
0.55
0.61
1.15
9.62
13.52
0.07
1991
1.52
4.45
0.99
0.59
0.64
1.39
9.57
13.58
0.07
1992
1.07
3.90
0.96
0.56
0.70
1.28
8.48
13.82
0.06
1993
1.07
3.81
1.05
0.65
0.71
1.38
8.66
1994
0.98
3.74
1.05
0.94
0.70
1.30
8.72
-------
12-May-97
GLOBAL TRACE GAS CONTRIBUTIONS TO WARMING, GLOWARM 3.0
INPUT INFORMATION
C02 Gwth
GQ2JD&Qay Option
SuifateJnpyi
Tropo.03
1ST YR:
1980
im-im
IPCC-1992}
1
1980 Sulfate Impact
PPM-03/KG:
; END YR:
2100
1.85%
Kastlng Model}
2
-1.65 watts/sq.m
CH4
-.IMPACT YR:
2100
2Q3£K21QQ
C02 Option =
1
Average for North Heml
3.50E-15
CONTROL CASE NO:
1
0.780%
OUTPUT SUMMARY
0.8 {S04 effect.expon<
NOx
1=BASE,6=Control, 7=Cap
CH4 Gwth
Equil.Warming
.JLot 185JL to.1.980
3.80E-14
START CONTROL
2000
1980-2030
4.09 Deg.Celcius
EQUIL.WARMING
CO
;ANN.EMIS.CONTROL:
1.0%
1.170%
0.54 Deg.Celcius
6.40E-15
CFC PHASEOUT?
1
2030-2100
Transient Warming=
NMHC
(1=YES,2=NO,3=see B9)
0.820%
2.07 Deg.Celcius
Transient Warmings
3.60E-14
Effect of CFC Warming
0.5
S02 Gwth
0.48 Deg.Celcius
Actual/Derwent=
% CFCs to H FC-134a
0.35
1990-2030
CH4 ppm N20ppm C02ppm
1980
0.3
METHANE LIFETIME
11
1.20%
4.55 0.388
812
CH4 ppmC02ppm
Transient Response
ATM.SENSITIV.2X,degree
2.5012030-2100
Rate of Eq.Warm.
0.034
pre-lnd.
0.8
280
1
0.35%
(Degree C per Year)
1980
1.65
338
4=slowest,5=slow
1=base,2=fast
3=fastest
Fig. 1: Glowarm Model Input and Output Screen
-------
• Lowest
<* Most Likely
© High
-*¦ Highest
Fig. 2: Projected Realized Warming Vs. Time Since
1800 (actual warming 1800 to 1980)
-------
ro
CO
^ Bass Case
-A¦ High Case
S Low Case
-e- ControhHigh Case
Control:Base Case
Fig. 3 : Projected Realized Global Warming for Three Business as Usual
and Two Control Cases
-------
4>
C
as
E
=3
•c
-Q
'5
cr
LU
1ST YR:1980; END YR:2050:Uncontrolled Eq.Warming=2.2
Others
03:xCH4
Sulfates
Fig. U- Gas Contributions to Warming
-------
3
U I
a
u
W)
CJ
et>
W
03:xCH4CFCs N20 Others Sulfates
I
-1
BASE WARMING(Equii.) ~ WARM.PREVENTED
Fig. 5: Warming Prevented by 2000 Emission Control
(period 1980 - 2050, 1% per yr. control)
-------
c.
0.4
0.2
0.0%
1.0%
2.0%
3.0%
-2.0%
Annua! Mitigation Rate
C02
-0"*
Methane
03 Precursors
N20
Other
Fig. 6: Warming Abated by Gas vs. Mitigation Rate
-------
20
Ui
to
V)
V
d
c
©
a
0
=5
1
"O
o
a
o
¦a
s-
«
U
15
10
•t * u «ll it»»ii * »\« * n Ik t
¦ AArtMrtAllMrtHflllKf
I1.1.«. »• h i.».I»i>m ftM M
J55555555555555
ssssms&s
~ Mexico
BS Franc*
ED Italy
ea Canada
23 Poland
ra United Kingdom
¦ India
~ Japan
¦ Germany
CD People'a Rep. of China
S USSR
SB United State*
1960
1970
1980
1988
Fig. 7: Historical Emissions of C02 by Country (12 largest emitters in 1988)
-------
(0
V
c
c
o
•+*
c
o
©
•o
X
o
c
o
n
hm
(a
O
I
rrrrt
Brazil Germany India Mexico UK USSR
China France Japan Poland USA
¦ Steam Cod
(22 Brown Coal/Ugnite
£3 Coke Oven Coke
B Residual Fori Oil
33 Gas OiVDiesd Oil
03 Motor Gasoline
¦ Jet Fuel
m Other Oil
¦ Liquefied Petroleum Gas
CD Natural Gas
SI Other
Fig. 8: Recent CO2 Emissions by Country by Fuel
-------
¦ OECD
DUSSR
G China
i Africa
0 Latin America
o Rest of Asia
¦ Mid.East
Fig. 9: Projected C02 Emissions for Selected Countries
(Cumulative bar chart; actual values 1960-1988)
34
-------
(A
fl>
C
C
o
c
o
o
T3
X
O
e
o
n
CO
o
i United States
~ USSR
r China
e Other Asia
- Germany
Japan
Other OECO
India
* United Kingdom
o Middle East
2000
2050
2100
Fig. 10: Projected C02 Emissions for Selected Countries
(line chart; actual values 1960 - 1988)
35
-------
Base (Uncontrolled), 1% ann.control & emiss.cap
2.5
O
o
£
O)
o
T3
CD
C
ra
$
¦a
o
N
15
— ^
> 4
& >
J
V"
\
I
1
¦ Base Case
1 %control@2000
¦A Cap Emiss.@2000
1980 2000 2020 2040 2060 2080 2100 2120
Fig. 11: Projected Global Warming for the Base Case and Two Mitigation Scenarios
-------
Projected C02 Emission*
-t- Population
•*- Economic Activity
-€/- Mitigated C02 Emls8.(1% per year)
Fig. 12: Projected Growth of Economic Activity, Population, andCOz Emissions
(unitized at 1990 levels)
-------
u>
CO
1stYR: 1980; ENDYR: 2050; Uncontrolled Eq. Warming = 2.3
u
i
D£
N
75
£
1.4
1.2
1
0.8
0.6
i
r
\
i
a'
}
/
/
r
1
/
¦ 1% Control Case
^ 0% Growth(Cap Case)
A* No Control
1990 2000 2010 2020 2030 2040
Year Control Starts
Fig.. 13: Projected Realized Warming Vs. First Year Control
-------
Biomass
51.06 kg C
7.49 kg H
51.53kg O
0.15 kg N
OjOakg S
0.792 kg ash
Steam 19.5 mots
Gasfflsr
800*C
Combustor
Unrsactad
carbon
0.549 mol
Natural gas
(fuel) 2-59 mo is
Steam 1.7 mols
H,0 condensate
15.0 mols
Fig. 14: The Hynol Process
39
-------
a>
E
a>
o
!c
0)
>
i-
0)
CL
W
c
E
o
co
CO
T—
O
|i
O
z
E
o
ZZ-
i—
o
D
a
o
cc
Q.
_J
LU
u.
Gasoline In current vehicles
NATURAL GAS PRICE, $/GJ
ASSUMPTIONS
1. Production cost of gasoline is assumed constant at $ 0.60/gal ($ 0.16/1 iter)
2. Fuel economy of conventional gasoline vehicles is assumed to be 27 miles/gal (11.3 ion/liter)
3. Optimized methanol vehicles using M100 are 27% more fuel efficient than gasoline vehicles
4. Hynol plant size is 7900 tonnes/day
5. Biomass is delivered at $61/tonne
6. Optimized Hynol process produces methanol at $ 0.42/gal ($ 0.11/liter)
Fig. 15: Hynol Methanol Vs. Gasoline Used in Vehicles
with Internal Combustion Engines
40
-------
,ro,roT rorrxj T3 1QQ TECHNICAL REPORT DATA
IN it IVlrt i->~ Klr_r 1S» (Please reed Instructions on the reverse before compU
1. RCPORT NO. 2.
600/A-98/11 3
3
5. REPORT DATF
4. TITLE AND SUBTITLE
Renewable Technologies and Their Role in Mitigating
Greenhouse Gas Warming
6. PERFORMING ORGANIZATION CODE
7. AUTHOB(S)
Frank T. Princiotta
8. PERFORMING ORGANIZATION REPORT NO.
9. PERFORMING OR0ANIZATION NAME AND ADDRESS
See Block 12
10. PROGRAM ELEMENT NO.
11. CONTRACT/GRANT NO.
NA (Inhouse)
12. SPONSORING AGENCY NAME AND ADORESS
EPA, Office of Research and Development
Air Pollution Prevention and Control Division
Research Triangle Park, NC 27711
13. TYPE OF REPORT AND PERIOD COVEREO
Published paper; Thru 4/97
14. SPONSORING AGENCY CODE
EPA/600/13
is.supplementary NOTES APPCd project officer is Frank T. Princiotta, Mail Drop 60, 919/
541-2822. 5th U. S./Dutch Int. Symp, Noordwijk, The Netherlands, 4/13-17/97.
i6. abstractpaper discusses the role that renewable and other mitigation approa-
ches could pla}r in ameliorating projected greenhouse gas (GHG) warming. (NOTE:
Human activity has led to an increased atmospheric concentration of carbon dioxide
(C02), methane (CH4), and other gases which resist the outward flow of infrared
radiation more effectively than they impede incoming solar radiation. This imbalance
yields the potential for global warming as the atmospheric concentrations of these
gases increase.) The paper discusses: the range of projected warming: the relative
importance of the various GHGs; the major and projected sources of C02; the emis-
sion controls that achieve various levels of GHG warming mitigation; candidate miti-
gation technologies, both on the end-use side and the production side; and some of
the economic, institutional, and other barriers that hinder commercialization of one
particular renewable technology, the Hynol process.
17. KEY WORDS AND DOCUMENT ANALYSIS
2. DESCRIPTORS
b.IDENTIFIERS/OPEN ENDED TERMS
c. COSATI Field/Gioup
Pollution
Greenhouse Effect
Carbon Dioxide
Methane
Pollution Control
Stationary Sources
Greenhouse Gases
Renewable Technologies
Global Warming
Hynol Process
13 B
04A
07B
07C
18. DISTRIBUTION STATEMENT
Release to Public
19. SECURITY CLASS (ThisReport)
Unclassified
21. NO. OF PAGES
40
20. SECURITY CLASS (This page)
Unclassified
22. PRICE
EPA Form 2220-1 (9-73)
------- |