A new policy brief from Institute for Local Self Reliance criticizes the authors of two recent studies published in Science for advancing a conclusion not supported by their own studies. ILSR’s paper notes that the vast majority of today’s ethanol production comes from corn cultivated on land that has been in corn production for generations. Since little new land has come into production, either directly or indirectly, the current use of ethanol clearly reduces greenhouse gas emissions.
“The studies usefully estimate how much carbon will be released when new land is brought into crop production,” says David Morris, ILSR’s Vice President and author of Ethanol and Land Use Changes. “But the authors’ declarations that ethanol increases greenhouse gas emissions, a conclusion that has made headlines around the world, is not supported, and may be contradicted, by their own data.”
“Since little new land has come into production, either directly or indirectly, the current use of ethanol clearly reduces greenhouse gas emissions,” says Morris, who served six years on an Advisory Committee on biomass to the U.S. Departments of Energy and Agriculture.
The studies fail to recognize the very low greenhouse gas emissions from advanced ethanol plants, plants that can reduce emissions by over 50 percent as compared to gasoline. Nor do the studies factor in the higher greenhouse gases that will be emitted when crude oil is extracted from unconventional sources like tar sands.
A controversial part of these studies examines the indirect impacts of growing energy crops. For example, if corn acreage displaces soybeans in the U.S., the authors assume that an equal amount of soybeans will have to be grown in the rest of the world to make up for that loss in animal feed. But a byproduct of corn ethanol production is a high protein animal feed called distiller’s grains. Indeed, distiller’s grains produce more protein per acre of corn harvested than is produced from an acre of soybeans.
The most contentious part of the studies may be the conclusion that when countries import less food and feed from the U.S., growing more themselves, that greenhouse gases increase. “The conclusion is not only counterintuitive, but will undoubtedly stir up considerable opposition by farmers and advocates of local food around the world,” says Morris, who also has served as an advisor to the energy administrations of Presidents Ford, Carter, Clinton and George W. Bush.
Similar critiques have been released by U.S. Department of Energy Researchers (see here and here)
- Ethanol and Land Use Changes – by David Morris, Institute for Local Self-Reliance, February2008