The ethanol mixed with the gasoline you buy has few proponents for a number of reasons. It reduces mileage in motor vehicles. It attracts water, an enemy of fuel tanks. And it corrodes rubber, plastic and some metal parts, particularly in small engines like those in outdoor power equipment.
On the other side are big players: corn growers, for whom ethanol is a cash cow, and the Environmental Protection Agency, which says it reduces greenhouse gases. But what if research proved that biofuels like ethanol actually increase greenhouse gases—even more than gasoline by itself? That’s the conclusion of a revolutionary study from the University of Michigan.
The study, headed by research professor John DeCicco and co-authors at the U-M Energy Institute (published in the August 25 issue of Climatic Change), used U.S. Department of Agriculture crop-production data to address the underlying assumption of biofuels’ value. This assumption involves two processes. The first is that the corn, soybeans and other plants used to manufacture biofuels remove carbon dioxide from the atmosphere in order to grow. Second, the biofuels made from these plants emit carbon dioxide as they’re burned for fuel. The accepted truth is that the two processes, in terms of carbon-dioxide exchange, cancel one another out. Descriptions of biofuels, as a result, use terms such as “inherently carbon-neutral.”
Steps on carbon-footprint models
This is what the study challenges, and it used actual crop data rather than carbon-footprint models like those underlying the federal Renewable Fuel Standard. In fact, the researchers’ analysis shows that during the recent ramp-up of U.S. biofuel production, the increased carbon-dioxide uptake by the crops offset just 37% of the CO2 emissions attributed to biofuel combustion.
“When it comes to the emissions that cause global warming, it turns out that biofuels are worse than gasoline,” said DeCicco. “So the underpinnings of policies used to promote biofuels for reasons of climate have now been proven to be scientifically incorrect.”
DeCicco voiced his hope that policymakers reconsider their support for biofuels. “What’s new here is that hard data, straight from America’s croplands, now confirm the worst fears about the harm that biofuels do to the planet.”