As the rush to petroleum substitutes gains momentum, a U study says a switch to biofuels would increase greenhouse gas emissions.
By TOM MEERSMAN, Star Tribune
Last update: February 7, 2008 - 11:22 PM
Renewable fuels such as ethanol have long been hailed as a cleaner-burning alternative to fossil fuels and a potent way to reduce the climate-changing gases pumped out of car tailpipes.
The 2007 Energy Act signed by President Bush last December doubles the nation's use of corn-based ethanol. Ethanol production in Minnesota, a pioneer of the technology, is expected to double during the next three years.
But research by Minnesota scientists is challenging the underpinnings of the biofuel rush. Ethanol and similar products may do more harm than good because of the changes they bring to the landscape, some scientists say.
The exploding demand for ethanol, soy diesel and other products is causing farmers to clear forests, grasslands and peat lands on a massive scale, unleashing far more carbon dioxide than is saved by the lower emissions of the biofuels, the study said.
"If we keep moving to get large amounts of energy by growing it on newly cleared land, which is what's happening around the world, we're going to be releasing much more greenhouse gas than the benefits we get from those biofuels," said David Tilman, ecology professor at the University of Minnesota and one of the study's authors.
The study, published Thursday in the online version of the journal Science, was funded by the National Science Foundation and the University of Minnesota. Another study published Thursday in Science, with estimates from economists at Iowa State University, concluded that corn-based ethanol could double greenhouse gas emissions, rather than reducing them, during the next 30 years because of the dramatic changes in land use.
Ethanol industry officials called the latest studies a simplistic analysis that does not include the economic benefits for those who grow biofuel crops in the United States and abroad, or the environmental cost of continuing to rely on petroleum.
This sort of thing makes me wish I hadn't allowed my subscription to Science to lapse.