David Pimental, a leading Cornell University agricultural expert, has calculated that powering the average U.S. automobile for one year on ethanol (blended with gasoline) derived from corn would require 11 acres of farmland, the same space needed to grow a year’s supply of food for seven people. Adding up the energy costs of corn production and its conversion into ethanol, 131,000 BTUs are needed to make one gallon of ethanol. One gallon of ethanol has an energy value of only 77,000 BTUS. Thus, 70 percent more energy is required to produce ethanol than the energy that actually is in it. Every time you make one gallon of ethanol, there is a net energy loss of 54,000 BTUs.
Mr. Pimentel concluded that “abusing our precious croplands to grow corn for an energy-inefficient process that yields low-grade automobile fuels amounts to unsustainable subsidized food burning”.
Related Comments (3)
Mr. Pimental is incorrect. More than a dozen recent studies over the last five years have proven that ethanol creates a positive energy balance. A recent study by the USDA showed ethanol to contain 67% more energy than is required to produce it. New technology developed by ethanol producers and plant builders have greatly reduced the cost of producing ethanol over the last ten years. The vast majority of scientists now acknowledge that ethanol produced from corn produces an unquestionable positive energy balance.
Hi Claire, do you have some references? I’d be curious to look at the studies.
Could you post a link to a site with the original study? Thanks.