“Energy outputs from ethanol produced using corn, switchgrass, and wood biomass were each less than the respective fossil energy inputs. The same was true for producing biodiesel using soybeans and sunflower, however, the energy cost for producing soybean biodiesel was only slightly negative compared with ethanol production. Findings in terms of energy outputs compared with the energy inputs were:
* Ethanol production using corn grain required 29% more fossil energy than the ethanol fuel produced.
* Ethanol production using switchgrass required 50% more fossil energy than the ethanol fuel produced.
* Ethanol production using wood biomass required 57% more fossil energy than the ethanol fuel produced.
* Biodiesel production using soybean required 27% more fossil energy than the biodiesel fuel produced (Note, the energy yield from soy oil per hectare is far lower than the ethanol yield from corn).
* Biodiesel production using sunflower required 118% more fossil energy than the biodiesel fuel produced.” (source)
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Also check out the following link (gives a well-rounded view on the whole biofuel issue):
A Grist special series on biofuels
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March 20th, 2009 at 7:25 pm
Most of this comes from biased articles and a couple studies financed by oil companies. Ethanol is the best alternative to gasoline and the oil companies are running scared. The studies by Pimentel are deeply flawed and run counter to many other studies that have found that the net return on energy invested for ethanol is indeed positive. The study you quote would make it seem that ethanol is only possible through the use of fossil fuels, that couldn’t be further from the truth since people have been making alcohol for thousands of years. Ethanol was the original fuel for Henry Ford’s model Ts and was supplanted by gasoline only through the manipulation of the political process by Rockefeller. Prohibition put the final nail in the use of ethanol as a motor fuel from which it did not recover. Did you ever wonder how Japan and Germany were able to keep their war machine running after allied forces cut their access to petroleum? It was because they used ethanol which allowed their airplanes to fly faster and higher. This fact puts the lie to oil company propaganda about negative net return for ethanol. In any case if it were true it is because ethanol is produced in an inefficient fashion. This was true in the early days of petroleum refining as well, they wasted great amounts of petroleum through inefficient processing. If you view the production of ethanol through the narrow linear paradigm associated with the use of fossil fuels then it will indeed not look as attractive. The majority of the corn produced in this country is used as animal feed. Ethanol processing simply removes the part of the corn (starch) that ruminant animals cannot process anyway. In fact feeding cattle the byproducts of ethanol production makes them gain weight 30% faster than feeding them plain unprocessed corn. Admittedly, corn is produced in a way that abuses the soil and is energy intensive and unsustainable. If instead better practices that rotate crops and use biologically sustainable methods to raise energy crops are utilized ethanol will fit in nicely. There are much better crops that can be used for raising ethanol feedstocks such as cattails (1500 gal/acre) or jerusalem artichokes (1000 gal/acre). These crops can be raised on marginal land with little if any fossil inputs. Cattails for instance can be grown in ponds of sewage products that will not only produce ethanol feedstock but soaks up the excess nutrients present preventing the eventual eutrophication of lakes and bays.