[Plant-education] Re: bioethanol
David R. Hershey
(by dh321 At excite.com)
Sat Jan 6 19:13:16 EST 2007
Bioethanol could be produced without any fossil fuel energy.
Moonshiners used to do it in early America. However, few, if any,
farmers would be willing to go back to using only animal-driven farm
machinery and manual labor to grow and harvest crops.
Although an exciting time, I believe that we are also in a
disappointing time for U.S. federal energy policy. There are many
innovative ideas out there but the federal government is not embracing
most of them. Huge amounts of tax dollars are being wasted on
bioethanol that could be better spent on newer, more efficient
technologies. Pimentel and Patzek (2005) identified the danger of
inaccurate reports on the energy efficiency of bioethanol production,
i.e. "this misleads U.S. policy makers and the public." Pimentel and
Patzek (2006) also mentioned environmental and ethical problems with
Bioethanol is a politically attractive boondoogle and an old technology
to fuel gas-guzzling SUVs. Except use of bioethanol as a fuel additive,
it is illogical to use more than one energy unit of fossil fuel to
produce one energy unit of bioethanol. It would be cheaper and more
efficient to just use the fossil fuel directly.
If the U.S. had a sensible energy policy, we would be widely embracing
a variety of more efficient technologies such as wind power, solar
power, energy conservation, hybrid cars, electric cars and lightweight
Hypercars. The aim of Hypercars is to get 3 to 5 times the fuel economy
of current cars. One example of how bioethanol may slow development of
better technologies was Ford's decision in June, 2006 to abandon their
hybrid car program to concentrate on alternative fuel, especially E85,
The holy grail of bioethanol is cellulosic ethanol, which could use
virtually any plant biomass. It is not clear if cellulosic ethanol will
ever be economically viable. Pimentel and Patzek (2005) concluded that
corn bioethanol required 29% more fossil fuel energy than in the
ethanol produced, bioethanol from switchgrass and wood required 50% and
57% more fossil fuel energy, respectively. Research on cellulosic
ethanol should be continued, but we cannot yet count on cellulosic
ethanol as an important part of our liquid fuel supply. Even the most
optimistic predictions indicate that bioethanol production could only
partly meet the world's transportation fuel needs. The entire U.S. corn
crop converted to bioethanol would replace just 6% of our petroleum use
(Pimentel and Patzek 2006)
Even the overly-optimistic calculations of Michaal Wang from the
Argonne National Laboratory indicate that it takes 0.74 energy units
from fossil fuel to produce one energy unit of ethanol from corn. That
is not an efficient conversion and still relies very heavily on fossil
It is a popular myth that the powdered beverage mix, Tang, was a
product of the U.S. space program. Tang was first marketed in 1957 by
General Foods and was not used on a space flight until the 1965 Gemini
I'm not sure that the U.S. space program is a good example of a
government investment that made "economic sense" considering the tens
of billions of tax dollars spent. Many of the accomplishments of the
U.S. space program are intangibles such as national pride, more
knowledge about space, launching a 77 year old former senator into
space to set the record for the oldest man in space, museum exhibits
and educational programs that also promote NASA, such as the NASA
Tomato Seeds in Space Project.
David R. Hershey
Pimentel, D. and Patzek, T.W. 2006. Green Plants, Fossil Fuels, and Now
Biofuels. BioScience 56: 875.
Pimentel, D. and Patzek, T.W. 2005. Ethanol Production Using Corn,
Switchgrass, and Wood; Biodiesel Production Using Soybean and
Sunflower. Natural Resources Research 14: 65-76.
Argonne National Laboratory Ethanol Study
Tang by Kraft Foods
Robinson, Dr. David wrote:
> But doesn't the current period we are in now (where bioethanol is made
> from corn and other intensively-farmed crops) just a transitional phase?
> Once the technology is improved, and the infrastructure is better
> established, and the demand for ethanol increases, isn't it feasible
> that other sources for synthesizing ethanol could start to be utilized?
> These other sources might include: yard trash, garbage, recycled food,
> biomass from weedy fields, manure, restaurant waste, sawdust from lumber
> mills, etc.
> It makes sense that using carbon energy generated in contemporary times
> has to better in the long run than harvesting fossil fuels that were
> generated millions of years ago....not only in terms of carbon dioxide
> in the atmosphere, but in terms of petroleum supply/demand.
> And who says farmers have to grow corn in such a petroleum-rich fashion,
> anyway? If agriculture used less chemical fertilizer and used methods
> like crop rotation, green manure, animal manure, and other so-called
> sustainable farming techniques wouldn't David Pimental's calculations
> have to be redone? Maybe that's what we should be pushing for...making
> agriculture less petroleum-dependent, rather than attacking the use of
> corn for bioethanol production.
> And isn't it the "job" of government to subsidize ideas like this when
> they don't make economic sense in the beginning??? Aren't we just in
> the earliest stages of implementaion? Eventually demand for bioethanol
> will pick up, prices will increase, the technology will get better, and
> the alternatives (fossil fuel) will become less attractive and less
> available. Then the government can stop subsidizing the biofuel
> industry, and it can take-off by itself.
> For instance, think of all the money invested in the U.S. space program
> back in the 1960s...it didn't really make economic sense then (I do like
> to drink Tang though....ha). But eventually it did pay off....even more
> in the future than now.
> So we don't have to nix the idea from the beginning, just because its
> not totally economically logical at this very moment....I think this is
> a very exciting time.
> P.S. I don't work for agri-industry!
> Dave Robinson, Chair
> Biology Department
> Bellarmine University
> 2001 Newburg Road
> Louisville, KY 40205
> -----Original Message-----
> From: plant-ed-bounces At oat.bio.indiana.edu
> [mailto:plant-ed-bounces At oat.bio.indiana.edu] On Behalf Of David R.
> Sent: Saturday, January 06, 2007 12:08 AM
> To: bionet-plants-education At magpie.bio.indiana.edu
> Subject: [Plant-education] Re: bioethanol
> Tad Patzek of the University of California, Berkeley, and David Pimental
> of Cornell University have published detailed analyses that indicate
> that bioethanol production requires more energy as fossil fuel than
> present in the bioethanol.
> The National Corn Growers Association has analyses from consultants and
> federal government scientists that show a net gain in energy for corn
> bioethanol production.
> I find Patzek and Pimental's analyses much more believable. If corn
> ethanol production yielded more energy than it required, the corn
> ethanol industry would be able to run all their fertilizer and pesticide
> factories, farm machinery and ethanol production facilties on bioethanol
> rather than fossil fuels and still have a net production of ethanol. I
> have never heard this even being attempted on a pilot project basis.
> Large U.S. government subsidies for the corn bioethanol industry are
> attractive politically for several reasons. They create jobs in farm
> states. They make it appear that the government is doing something to
> counter global warming. They make it appear that the government is
> working to reduce dependence on foreign oil.
> Patzek, T.W. 2006. Thermodynamics of the corn-ethanol biofuel cycle.
> updated web version of Critical Reviews in Plant Sciences 23: 519-567
> National Corn Growers Association. The Truth About Ethanol - Addressing
> the Myths of the Pimentel/Patzek Study
> Google search for ethanol boondoogle
> David Alan Walker wrote:
> > Agricultural food production in the UK is reckoned to be about the
> > most efficient (yields per acre) in the 'Western World'. Yet, if all
> > of the sums are done, it turns out that there is no net energy gain.
> > It is, in fact, "a very inefficient way of turning oil in to
> > potatoes". Where does this leave bioethanol production from
> conventional and unconventional crops?
> > Clearly many of the inputs are about the same but then there is the
> > additional, inescapable energy cost of distillation. O.K.,
> > distillation processes are more energy efficient than they were a few
> > decades ago but, in the end, there is no way round the laws of
> > physics. Does any one have itemised details of the energy inputs
> involved ?
> > Many thanks,
> > David
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