http://auto.howstuffworks.com/ethanol-facts.htm According to Dr. Pimental, it takes more energy to produce a given amount of ethanol than there is energy available in that ethanol. According to his calculations, producing corn and processing it into 1 gallon of ethanol requires 131,000 BTUs of energy; but 1 gallon of ethanol contains only 77,000 BTUs. But not all scientists agree with Pimental's analysis regarding energy efficiency. Dr. Michael Wang of the Argonne National Laboratory finds that it requires 0.74 million BTUs of fossil fuels to get 1 million BTUs of ethanol to market. That would mean a net gain in energy, not a net loss. Pimento estimates that powering a car for a single year using ethanol would require 11 acres of corn. the ethanol industry is actually burning large amounts of gasoline to produce ethanol, and that ethanol contains far less energy than the gasoline they consumed to produce it.