Several studies have intimated it, but two blockbusters published in the lofty journal "Science" yesterday confirm that biofuels cause more emissions than fossil fuels when everything is taken into account.
Both studies take a detailed look at the effects of converting large tracts of land worldwide into cropland used to raise fuel. While it is true that biofuel crops such as sugarcane, corn, switchgrass and the like absorb greenhouse gases as they grow, they absorb far less than rain forests and even scrubland. Also, turning plants into fuel creates its own emissions, especially when transportation is figured into the equation.
The "Science" article, "Use of U.S. Croplands for Biofuels Increases Greenhouse Gases Through Emissions from Land Use Change,"(subscription), maintains that the clearance of grassland for fuel releases 93 times the amount of greenhouse gas that would be saved the fuel made annually on that same land. Of course, not everybody agrees with the study.The Renewable Fuels Association, a coalition of ethanol producers, called the researchers' view of land-use changes "simplistic" and said the study "fails to put the issue in context."
"Assigning the blame for rainforest deforestation and grassland conversion to agriculture solely on the renewable fuels industry ignores key factors that play a greater role," said Bob Dinneen, the association's president. Even so, the article prompted a letter to President Bush and to Speaker Nancy Pelosi from 10 eminent U.S. ecologists and environmental scientists, including four members of the National Academy of Sciences, to pursue policies that ensures biofuels are not produced on productive forests, grassland or cropland.
Sources: Science, AP, Mongabay
