Could Ethanol Add To Global Warming?
- Feb 12, 2008 2:00 PM EST
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The Associated Press reports that contrary to earlier studies, widespread use of ethanol from corn could result in nearly twice the greenhouse gas emissions as the gasoline it would replace, researchers concluded Thursday. It turns out that despite the recent buzz about cars that could run on ethanol and the push for biodiesel, past studies didn't take into account one huge aspect of biofuel production: the changes in land use that would occur if we began to depend on ethanol made from corn or switchgrass.
"Using good cropland to expand biofuels will probably exacerbate global warming," concludes the study published in Science magazine. "Right now we're making almost exclusively the wrong biofuels," said Tim Searchinger, a research scholar at Princeton University's Woodrow Wilson School of Public and International Affairs and lead author of the study.
The report brings into question a number of U.S.-backed efforts to develop biofuels as a way to wean our dependence from foreign oil. In the process, we could trade one environmental disaster for another. Burning biofuels produces less carbon dioxide in the atmosphere than burning regular gasoline—that much is known. But in the rush to expand and produce more biofuels based on corn and other feedstock, we would end up releasing much more CO2 by converting grasslands and forest into croplands.
"After taking into account expected worldwide land-use changes, corn-based ethanol, instead of reducing greenhouse gases by 20 percent, will increases it by 93 percent compared to using gasoline over a 30-year period," the article said. "Biofuels from switchgrass, if they replace croplands and other carbon-absorbing lands, would result in 50 percent more greenhouse gas emissions."
The report said that biofuel made from waste products would be a much better source and wouldn't require land use changes.