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This study was published by the University of Minnesota Alumni Association
Listen to the hype about corn-based ethanol and it's easy to get the wrong impression.
"The world's demand for energy will never stop," intones the narrator of a television ad by Illinois-based Archer Daniels Midland Company, the largest fuel ethanol producer in the United States, "which is why a farmer is growing corn . . . and why ADM is turning these crops into biofuels." Read ADM's fuel brochure, and you'd learn that "ethanol not only extends gasoline supplies--it also provides an environmentally friendly alternative to fossil fuels."
Or check out the South Dakota-based American Coalition for Ethanol, an ethanol industry lobbying group, which contends that ethanol production "moves our nation toward energy independence."
Or click on the Minnesota Department of Commerce Web site: "Minnesota's ethanol mandate helps reduce our reliance on imported petroleum. Nearly all gasoline sold in Minnesota is blended with 10 percent ethanol, which allows us to offset our demand for gasoline by 10 percent."
Or listen to Minnesota Governor Tim Pawlenty (B.S. '83, J.D. '86), who has promoted legislation doubling the amount of ethanol in gasoline to 20 percent by 2012. The self-proclaimed "most pro-ethanol governor in the country" argues that Minnesota can become the "Saudi Arabia of renewable fuels." The state government has subsidized the construction of 16 ethanol plants, with another on the way. These plants convert 148 million bushels of corn, 12 percent of the state's crop, into 550 million gallons of ethanol annually.
Listening to these endorsements, you'd think turning corn into motor fuel is a good thing, a formula for protecting the environment and weaning the nation from foreign oil. But you'd be wrong.
"The effect on foreign energy independence is minimal," contends Jason Hill (Ph.D. '04), an applied economics researcher at the University of Minnesota. "It can have only a minimal effect on our energy consumption." Hill is the lead author of a University study published in summer 2006 on the environmental, economic, and energy costs of corn ethanol and soy-based biodiesel.
"Why should we take two very limiting factors for human quality of life--food and energy--and convert one into the other?" asks Regents professor David Tilman, a world-renowned University ecologist and lead author of a new study about prairie grasses as a biofuel source.
According to the University studies, the environmental benefits of corn-derived ethanol are limited and are offset by serious environmental drawbacks. And ethanol, as currently produced, won't make us energy independent--unless we expand the Corn Belt to every state in the union.
Here are five reasons why ethanol fails to live up to the hype:
[ 1 ] Ethanol production requires almost as much energy as it yields.
A moonshiner, or anyone who has spotted steam billowing from a Minnesota ethanol plant, can tell you it takes a lot of energy to distill fermented corn into nearly pure alcohol. What's more, a tremendous amount of energy resources are used simply to grow corn; the biggest agricultural input is nitrogen fertilizer, made from natural gas.
In the U study published last summer, in the journal Proceedings of the National Academy of Sciences, researchers tried to account for all the energy inputs of the process, from growing corn (even the energy use of farm households) to energy burned in transportation and the construction of processing plants. They found that corn-derived ethanol yields only 25 percent more energy than is required to make it. (Studies by researchers at Cornell and Berkeley even contend that ethanol actually produces less energy than goes into its production, though U of M researchers dispute those findings.)
Burning fossil fuels to make ethanol can be justified, to some extent. Not all fuels are created equal, explains Douglas Tiffany (B.S. '74, M.S. '77), study co-author and research fellow in the University's Department of Applied Economics. "Some of them are much more valuable to us." Ethanol is a much more convenient and versatile fuel than coal, for example. You can't run a car on wood or coal, but you can on gas and ethanol.
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