A broad new study by University of Minnesota researchers is providing more evidence that ethanol from corn delivers more fossil energy than is required to produce it. The study shows the process delivers 25 percent more energy than is used in producing it. However, much of the positive energy balance comes from an ethanol by-product: animal feed. More importantly, the study shows the net energy gain from
fuel derived from soybeans is 93 percent, a much more attractive yield. Biodiesel from soybeans also has the added advantage of needing significantly less fertilizer and pesticides, which cause soil and water pollution. Alternative crops such as switch grass will offer even better results, according to the study, with higher positive energy balances, and even less need for fertilizers and pesticides. One of the major challenges for an increase in
production is the availability of feedstock. Currently, 14.3 percent of corn grown in the U.S is converted to ethanol, replacing only 1.72 percent of gasoline usage.
[Source: Renewable Energy Access]