[permaculture] carbon sequestration
hseaver at gmail.com
Wed Mar 12 15:33:29 EDT 2008
woodsjay at cox.net wrote:
> Where is the requested link to all these dastardly actions.
>From David Blume's "Alcohol Can Be a Gas - Fueling an Ethanol Revolution
for the 21st Century"
Busting the myths
Myth #1: It Takes More Energy to Produce Alcohol than You Get from It!
"If they can get you asking the wrong questions, they don't have to worry
about answers." -- Thomas Pynchon
Most research done on ethanol over the past 25 years has been on the topic
of energy returned on energy invested (EROEI), or energy balance. In
Appendix A, we detail how public discussion of this issue has been
dominated by the American Petroleum Institute's aggressive distribution of
the work of Cornell professor David Pimentel and his numerous studies. We
cite his distortion of key calculations, his unfamiliarity with farming in
general, his ignoring of studies from Brazil that disagree with him, and
his poor understanding of the value of co-products and their contribution
to an accurate portrayal of energy accounting in the ethanol manufacturing
process. In fact, he stands virtually alone in portraying alcohol as
having an EROEI that is negative -- producing less energy than is used in
its production (see Appendix A, Figure A-2).
In fact, it's oil that has a negative EROEI. Because oil is both the raw
material and the energy source for production of gasoline, it comes out to
about 20% negative. That's just common sense; some of the oil is itself
used up in the process of refining and delivering it (from the Persian
Gulf, a distance of 11,000 miles in tanker travel).
As Dr. Barry Commoner of the Center for the Biology of Natural Systems
once said, "It's always possible to do a good thing stupidly,"  and
some existing scenarios for making alcohol on a grand scale prove just
that. However, the most exhaustive (and least-cited) study on the energy
balance, by Isaias de Carvalho Macedo of Brazil, shows an alcohol energy
return of more than eight units of output for every unit of input -- and
this study accounts for everything right down to smelting the ore to make
the steel for tractors. 
But perhaps there's a more important measurement to consider than EROEI.
What is the energy return for fossil fuel energy input? Using this
criterion, the energy returned from alcohol plants per fossil energy input
is much higher. Since the Brazilian system supplies almost all of its
energy from biomass, the ratio of return could be positive by hundreds to
1. "The Plow Boy Interview," Mother Earth News, March/April 1990
2. Isaias de Carvalho Macedo, "Greenhouse Gas Emissions and Energy
Balances in Bio-Ethanol Production and Utilization in Brazil," Biomass and
Bioenergy 14:1 (1998), 77-81.
3. Larry Rohter, "With Big Boost from Sugar Cane, Brazil Is Satisfying Its
Fuel Needs," New York Times, April 10, 2006, Sec. Al.
ETHANOL AND EROEI: HOW THE DEBATE HAS BEEN DOMINATED BY ONE VIEW
FOR 25 YEARS, DAVID PIMENTEL AND, IN RECENT YEARS, TAD PATZEK HAVE BEEN
RESPONSIBLE FOR THE ACADEMIC BASIS FOR MOST OF THE ANTI-ETHANOL
SENSIBILITIES IN THE MAINSTREAM PRESS.
Fig. A-1 Dr. Pimentel's tractor. This enormous 7000 series John Deere is a
close match to the seven-ton tractor in Dr. Pimentel's 2005 study. It can
pull a 12-row corn planter that could plant the entire farm in under four
hours (in air-conditioned comfort). Tractors of this size are used on
farms up to 25 times the size of the farm described in Dr. Pimentel's
For 25 years, David Pimentel, Ph.D. at Cornell University, and, in recent
years, Tad Patzek, Ph.D. at the University of California, Berkeley, have
been responsible for the academic basis for most of the anti-ethanol
sensibilities in the mainstream press, managing perceptions that have even
leaked into Hollywood television (a 2005 episode of The West Wing was an
example). Although dismissed by academics in the field, their studies
continue to receive extensive coverage in both business and environmental
circles. Political realities today cannot reverse the damage done.
Pimentel, now approaching 80 years of age, is a darling of the Peak Oil
movement. He and Dr. Patzek have been essentially alone in publishing
studies alleging that production of alcohol fuel, among other things:
- Has a negative energy balance;
- Is an unethical use of food;
- Pollutes the air;
- Costs the consumer money via subsidies;
- Takes 61% more fuel to go the same number of miles;
- Produces 13 gallons of sewage for every gallon of alcohol produced.
Dr. Pimentel is an entomologist, a studier of bugs, and Dr. Patzek is a
physicist and engineer. Neither of them is trained in ecology. So they are
straying far afield. This was amply borne out in their recent study [l]
when both co-authors failed to catch their misuse of net primary
productivity, a very basic concept in describing world photosynthesis. 
In doing so, both also understate the photosynthetic efficiency of plants
in general and corn in particular (so it can't be dismissed as a typo) by
ten times, fully undermining their paper's first major conclusion that
plants are 100 times less efficient than solar panels.
Pimentel's lack of expertise also explains his continuing choice to
publish with the International Association for Mathematical Geology's
Nonrenewable Resources, now renamed Natural Resources Research, (which
handles "all aspects of non-renewable [author's emphasis] resources, both
metallic and non-metallic... "),  not a journal known for
peer-reviewing biological papers or those on renewable energy. His peer
reviewers all missed the same glaring errors mentioned above.
In their most recent study,  Drs. Pimentel and Patzek cite a
self-described "independent" DOE study by the Energy Research Advisory
Board (1980)  as their "credible" source as to why we should believe
their negative energy balance allegations. Far from being independent, the
study in question was actually led by Pimentel himself, who was employed
by Mobil Oil at that time. This was not disclosed to the DOE.  In light
of this, the conclusion of the ERAB study was not surprising: The U.S.
should abandon attempts at producing ethanol and instead rely on the Mobil
process for making synthetic gasoline from coal. Pimentel today still
champions coal,  while his co-author Dr. Patzek stumps for nuclear
The scandal that the study caused at the time resulted in South Dakota
Senator George McGovern convening a Senate investigation to probe whether
"scientists with ties to Mobil Oil ... would rob hundreds of thousands of
American farmers of the opportunity to benefit from gasohol development."
This dust-up should have ended any normal academic's career. Among
statured, publishing peer-reviewed scientists, no other study has come
close to confirming Pimentel's allegations -- and many are
uncharacteristically candid in pointing out his repeated use of
inappropriate or out-of-date data, or data so lacking in documentation as
to be unable to be evaluated. This is the equivalent of coming to blows in
Pimentel publicly claims to have never taken money from oil companies,
although he grants it's possible that oil companies have donated money to
Cornell, his sponsoring university. Yet be admitted in a 2004 radio
interview  that he took thousands of dollars, and that he was exposed
in 1982 by investigative reporter Jack Anderson as being secretly on the
payroll of Mobil Oil.  Following the 1982 exposé, Mobil Oil even took
out a large ad to defend Pimentel, while admitting that it paid him. 
Pimentel has been a prolific publisher of roughly 475 studies and appears
to almost never be at a loss for funding. That's rather unique in the
world of organic agriculture. For comparison, the entire USDA only got its
first full-time funded position studying organic agriculture a few years
Dr Pimentel's work in entomology and organic agriculture methods is
rigorous and well documented. When one compares that work to his work on
alcohol fuel, it would appear that two completely different people are
publishing. In 2005, he and Dr. Patzek claimed that it takes 29% more
fossil energy to make alcohol fuel than it contains. He almost
simultaneously published a very solid piece of work showing that
organically produced corn saved over 30% of the energy used to grow it
chemically.  Yet in his alcohol study he did not cite his own work in
positing his energy figures for ethanol production!
EROEI (energy returned on energy invested) is a way of evaluating how much
energy is used in production of a fuel or energy source. If the energy in
the fuel (measured as heating value) is greater than the energy used to
produce it, then the fuel is considered positive. So a positive EROEI of
25% would mean that the fuel contains 25% more energy than was used to
create it. If it takes more energy to make the fuel than is contained in
it, then the EROEI is considered negative.
In making his most famous allegation on EROEI, Pimentel relies on several
figures. Let's take his most controversial one, the energy it takes to
build farm equipment. Pimentel has been claiming for 25 years that his
inclusion of this embedded energy figure is what makes his study more
accurate. This figure is higher than every other item he cites for growing
corn, except for his hotly disputed figures for the energy embedded in
The farm equipment figure was first published in a 1980 book, which
Pimentel edited.  The first chapter was written by Otto Doering III
and was an attempt to characterize the energy that went into farm
equipment, starting with the metal being mined, smelted, and formed, and
including the oil that went into the tires -- a figure that was actually
higher than the energy cost of the steel. Although Pimentel has never said
so specifically, it is abundantly clear that this is where he obtained his
embedded energy data. Although Doering himself said that it was impossible
to accurately calculate the embedded energy in farm equipment  and
cautioned against using his study as evidence for that, Pimentel pays no
Fig. A-2 Comparative results of ethanol energy balance studies, 1995-2005.
Comparative Results of Ethanol Energy Balance Studies 1995-2005
In his 2005 study, he finally specifies that he is talking about a six- to
seven-ton tractor, an eight- to ten-ton harvester, and a smaller,
unspecified amount of other equipment not deemed sufficiently worthy to
assign a specific weight. Although in earlier papers he and Doering
assumed a 12-year life expectancy from or for the equipment, Pimentel
reduced it to ten years in 2005, apparently in order to keep his weight of
equipment per acre at his historically constant 55 kg/hectare.
At any rate, it is clear that this will be the last paper where he will be
able to claim such a significant energy figure for farm equipment. Why?
Now that he has finally committed to the size of the equipment in writing,
it's possible to measure the degree to which the energy figure is
overstated. Translated into U.S. measures, 55 kg/ha is 49 pounds per acre.
Since tractors don't last forever, Pimentel alleges that this is the
amount of the equipment that is used up in the farming of an acre of corn.
If we generously assume a total of 20 tons of equipment with a ten-year
life, as specified by Pimentel, we come to the mathematical conclusion
that the average farm using this equipment is only 81.6 acres, about
one-eighth of a square mile.  Farm equipment of this size and weight,
among the largest tractors made, can work about 2000 acres of corn or
sugarcane (more than three square miles). I could plant this entire
81-acre farm using this sized tractor before lunch! When you take into
account that the real-world average life of farm equipment of this size,
in both the United States and in Brazil,  is 25.7 years, not 10 years,
the size of Pimentel's farm shrinks to less than 33 acres. His reported
energy figure, therefore, is at least 61 times greater than reality.
But wait! Pimentel is counting the tractor energy starting from mining the
ore. In reality, steel and tire rubber in the U.S. contains on average 76%
recycled materia1 [19, 20] and is, of course, recycled again at the end of
its life. So Pimentel's figure is actually a minimum of 196 times too
high. Were we to pick nits (such as pointing out that large tractors like
this are phasing out their eight huge tires in favor of two rubber
bulldozer treads that use a fraction of the rubber), the figure is
probably about 500 times too high. Of course, these rubber tracks can be
made from alcohol-based synthetic rubber, further diminishing the
petroleum energy figure to statistical insignificance.
The average-sized corn operation in the United States is approaching 2000
acres and heading for 4000 acres in major corn-growing states. (Even
though the average-sized farm is less than 1000 acres, many farms are
rented out to make the operation much larger.) In 2003, the one year in
which Pimentel cites Hülsbergen [2l] instead of himself for the equipment
energy figure, one finds that the study site, an organic research farm in
Germany, was only about 40 acres, without a single stalk of corn grown
anywhere on it! Pimentel has had to quietly retract that citation in his
latest study and go back to citing himself. Even more embarrassing,
Hülsbergen showed that sugar beets had a much higher EROEI than either of
the grains in the study.
Isaias Macedo of Brazil has analyzed, in excruciating detail, the energy
involved in production of farm equipment, alcohol plant components, and
all travel associated with every aspect of producing and distributing
fuel. He is the recognized world authority on analysis of embedded energy
in agriculture. His study goes into exceptionally rigorous, verifiable
detail concerning both embedded energy and the greenhouse gases emitted at
each step of the process. Yet, oddly, Pimentel never once cites this
information -- nor mentions it in any of his studies, in any context. In
Macedo's study, alcohol from sugarcane garners a 9 to 1 positive energy
return.  What's even more important is that virtually none of the
energy used is fossil-fuel-based, so its ratio of renewable energy output
per fossil energy input is much, much higher.
In case after case, Pimentel's figures are dramatically overstated,
frequently by one to three orders of magnitude (tens to thousands of times
too high). Major examples over the years have included:
- Assuming far lower yields of corn per acre than the USDA unambiguously
- Assuming energy figures for irrigation when almost all corn depends
solely on rainfall; the figures he quotes are off by an order of magnitude
for the small amount of acreage that is irrigated; 
- Assuming application rates for fertilizer like lime at ten times the
- Assuming 90-mile transportation distances for grain, when the verifiable
figure historically is less than half that, while modern plants are being
based on less than 20 miles; 
- Assuming very high energy cost of nitrogen fertilizer (his largest
energy cost) by citing international figures, which are double to triple
the real energy cost in the U.S.;
- Assuming the energy to distill is very high by claiming fermentation
yields only 8% alcohol, when the real-life historical figure has been 15%,
but currently is well over 20%;
- Assuming the yield of alcohol per ton of corn is much lower than is
actually realized in modem alcohol plants;
- Assuming energy to run the plant is much higher that it is. For some
time now, plant manufacturers have provided a money-back guarantee that
the plant will consume less than 34,000 Btu/gallon, including the nearly
15,000 Btu required to dry the DDGS;
- Assuming that alcohol has to be dehydrated from 96% to 99+% purity
(which takes a separate energy step) for use as an auto fuel. (Somehow the
Brazilians missed this detail and blend 96% alcohol/4% water with their
gas without mishap);
- Assuming the energy for dehydration of alcohol is based on old
technology, compared to the modern, extremely low-energy-consumption,
pressure swing, corn grit or molecular sieve adsorption methods than have
been in use most of the last 20 years;
- Assuming the food eaten by the farmer as "gasoline equivalent" energy;
- Assuming high figures for the metal used in the alcohol plant by stating
unrealistically short working life and without taking normal metal
recycling into account;
-Assuming that all the energy used in the process should be attributed to
the alcohol, when about half of it needs to be attributed to producing
dried animal feed and carbon dioxide co-products;
- Assuming that liquid left over after fermentation is sewage to be
disposed of at the energy cost of running an aerobic sewage treatment
plant, when, in reality; none of the liquid waste is so treated. The
liquid is evaporated, and the condensed solubles are combined with the
dried by-product grains;
- Assuming that the liquid left over with its load of solubles is sewage
rather than stillage -- a source of methane capable of producing more
energy than is used in the entire plant. This is standard operating
procedure in India and is now being adopted in the U.S.  The leftover
liquid should be counted as an energy credit, not debit;
- Assuming that ethanol causes air pollution (from volatiles released in
the drying of grain), when in reality all alcohol plants now recover those
volatiles, burn them, and generate a positive energy return from them;
- Assuming that heat energy must come from fossil sources, when the
process energy of the majority of the alcohol fuel produced in the world
is made from renewable biomass energy sources;
- Assuming that corn is representative of alcohol production when it is a
minority crop in world alcohol production compared to sugarcane, beets
- Assuming that the DDGS is comparable to soybean meal in feed/energy
quality in the face of 100 years of experience and science demonstrating
that it is far more valuable than soybeans or the original corn it came
- Assuming, incorrectly, that the heating value of ethanol equates to
mileage, and then undervaluing ethanol by 39% in relation to gasoline.
Current production flexible-fuel cars in Sweden get roughly equivalent
mileage on both fuels, and dedicated alcohol engines get superior mileage
to their gasoline counterparts. 
- Assuming that all Btu are the same, and converting coal or natural gas
Btu to "gasoline equivalents" to inflate the apparent use of petroleum to
six times its actual use. (Although the current process energy used in
alcohol plants in the U.S. is either coal or natural gas, it certainly is
not petroleum. New plants are now being designed to eliminate all fossil
fuel use while self-producing their own natural gas);
- Assuming that the tax incentives provided to alcohol cost taxpayers
money, when it has been clearly demonstrated that the return to the
treasury is several times the cost of the incentives due to taxes
collected on alcohol fuel's domestic economic activity; 
- Assuming that farmers derive no benefit from alcohol production and that
it's all a plot by the big corporations to loot the treasury. The majority
of alcohol today is produced by farmer-owned cooperatives, not
transnational grain corporations.
To top all that off, when Pimentel changes his assumptions by as much as
1700% between 2003 and 2005, he diverts attention away from it by
switching the units of measure so that the change would not be apparent to
anyone, such as a reporter, who would try to compare it. In the chart
comparing his 2003 and 2005 studies (see Figure A-3), I've converted the
recent study to the units of measure (Btu) used in the prior study. You'll
notice that his net change figure, the one that reporters should make the
effort to compare, is barely altered (-4.95%), despite many assumptions
Pimentel is all for accounting for energy costs relating to alcohol
production, but does not consider energy gains from alcohol's use. He
accounts for the embedded energy of the tractor as a cost, but does not
include an energy credit for tripling the engine life of the thousands of
car engines that would be running on the alcohol produced by that tractor.
He is in favor of accounting for the transportation of all the materials
involved in making alcohol, but does not account for displacing the energy
required to power tankers 11,000 miles to deliver crude oil. He accounts
for the petroleum energy it takes to make tires, but neglects to mention
that the same tires can be made from alcohol (and were in World War 11),
or that the Archer Daniels Midland alcohol plant in Decatur, Illinois,
uses one-third of the waste tires in that state to fuel its boilers, and
therefore should garner an energy credit.
Perhaps Pimentel's most grievous misrepresentation has to do with the
value of DDGS. It is incontestably proven that feeding DDGS instead of the
original corn to animals increases meat or milk output (see Chapter 13).
This alone would destroy his energy balance studies. So he assiduously
avoids the energy credit for reducing the amount of feed to produce the
same amount of meat or dairy.
These omissions also make mincemeat of his attempt at the moral high
ground, of caring about feeding the world with our grain. If we fed a
large part of our animals' diet as DDGS instead of corn, we would have
more than enough surplus from this one act alone to feed every
malnourished person in the world, from the newly freed surplus grain. And
let's not forget that DDGS is a compact nutritious source of protein for
people, without the unneeded starch.
In this appendix, I have hit only the high points of the
misrepresentations contained in the studies by Drs. Pimentel and Patzek.
It should come as no surprise that no other statured scientists in the
world today concur with the conclusions made in the Pimentel studies.
But when the American Petroleum Institute cranks up its awesome press
release mill and wallpapers the entire world media, a contrived paper can
suddenly become the "truth" in the mind of the public. In an era when
corporate funding of research is the norm, you cannot expect members of
the scientific community to do the policing of their own that they once
did, when to do so might endanger their own funding and survival.
Fig. A-3 Creative concealment. When converted to common units, it's easy
to see how the change of units of measure masked the inexplicably
divergent figures of the two versions of the study. The technology
involved has not measurably changed during this period.
1. David Pimentel and Tad W. Patzek, "Ethanol Production Using Corn,
Switchgrass, and Wood; Biodiesel Production Using Soybean and Sunflower,"
Natural Resources Research 14:1 (2005), 65-76.
2. David Morris, The Carbohydrate Economy, Biofuels and the Net Energy
Debate (Minneapolis: Institute for Local Self Reliance, August 2005).
3. Guidelines for Contributors, Natural Resources Research,
php?option=com_content&task=view&id=113<emid=132> (April 2007).
4. Pimentel and Patzek.
5. Energy Research Advisory Board, Gasohol (Washington, DC: U.S. Dept. of
6. Jack Anderson, "Gasohol Program: Prey to Big Oil," Washington Post, May
7. Stephen Thompson, "Running on Empty?" Rural Cooperatives Magazine,
September 2005, www.rurdev.usda.gov/rbs/pub/sep05/running.htm.
8. David Pescovitz, "Ethanol Stirs Eco-Debate," Lab Notes: Research from
the College of Engineering. University of California, Berkeley 5:3 (March
9. "Science and Politics Don't Mix," in Mobil Oil ad, The New York Times,
June 19, 1980, Sec. A23.
10. Alexander E. Farrell, et al., "Ethanol Can Contribute to Energy and
Environmental Goals," Science Magazine, 311:5760 (January 27, 2006),
11. Public Planet, radio show, hosted by Jodi Selene, KVMR, Nevada City,
13. "Science and Politics Don't Mix."
14. David Pimentel, et al., "Environmental, Energetic, and Economic
Comparisons of Organic and Conventional Farming Systems," BioScience 55:7
(July 2005), 573-82.
15. David Pimentel, CRC Handbook of Energy Utilization in Agriculture
(Boca Raton, Florida, U.S.: CRC Press, 1980), 9-14.
16. Otto Doering III, in Pimentel, CRC Handbook of Energy Utilization in
Agriculture, 9-14. ["There is no precise way to account for the energy
used indirectly in agricultural production." ... "A tremendous amount of
virtually unobtainable information would be required to make a precise
accounting of the actual energy embodied in a specific stock of farm
machinery for any given farming operation."]
17. 40,000 pounds divided by 49 pounds divided by 10 years.
18. Dr. Josmar Pagliuso, Universidade de Sdo Paulo, Brasil, Unpublished
Data from Actual Experience of Sugar Cane Farmers Producing Table Sugar
and Alcohol Fuel Over 20 Years.
19. Energy Savings from Recycling, Consumer's Choice Council, May 2001,
<www.ems.org/cgi-bin/ Gprint2002.pl?file- Energy_policy.recycling.rx>
(July 8, 2005).
20. Management of Scrap Tires, U.S. Environmental Protection Agency,
<www.epa.gov/epaoswer/non-hw/ muncpl/tires/ground.htm> (July 8, 2005).
[Cites up to 80% recycling of tires, primarily into road asphalt.]
21. K.J. Hülsbergen, et al., "A Method of Energy Balancing in Crop
Production and Its Application in a Long-Term Fertilizer Trial,"
Agriculture Ecosystems and Environment 86 (2001), 307.
22. Isaias Carvalho Macedo, Energy Balance of the Sugar Cane and Ethanol
Production in the Cooperated Sugar Mills, CT Brasil, Ministério da Ciência
e Tecnologia, The United Nations Framework Convention on Climate Change
23. Michael S. Graboski and John McClelland, A Rebuttal to "Ethanol Fuels:
Energy, Economics and Environmental Impacts" by D. Pimentel (May 2002).
24. Hosein Shapouri, James A. Duffield, and Michael Wang, "The Energy
Balance of Corn Ethanol: An Update," Agricultural Economic Report 813,
U.S. Department of Agriculture (July 2002).
25. Nathan Leaf, "Big Farm Plant Is Planned," Wisconsin State Journal,
December 8, 2005, Sec. E-1.
26. Christoph Berg, World Fuel Ethanol Analysis and Outlook (April 2004), 5.
27. Matthew Brusstar, et al., High Efficiency and Low Emissions from a
Port-Injected Engine with Neat Alcohol Fuels (Washington, DC: U.S.
Environmental Protection Agency, Society of Automotive Engineers, 2002).
28. John M. Urbanchuk, Contribution of the Ethanol Industry to the Economy
of the United States (Renewable Fuels Association, January 2005), 1-4.
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