"There are a lot of other reasons to resist the lure of grain ethanol as a biofuel, here are just a few: (1) It takes one gallon of fossil fuel to produce 1.3 gallons of grain ethanol (not much gain); (2) Corn grain ethanol production promotes soil erosion (20 pounds of soil lost per gallon of ethanol); (3) The amount of corn required to fill one 25 gallon tank of gas could feed an person for a year; (4) Corn is an important export to developing countries, diversion to ethanol production may strain our capacity to supply these countries; (5) Ethanol cannot be transported by pipeline; (6) Ethanol plants demand large volumes of water and generate waste water.
The other major biofuel slated for development is cellulosic ethanol which is produced from logging residues and biomass crops. Cellulosic ethanol has a positive energy balance (about 5:1 units of ethanol per unit of fossil fuel), stores carbon, and can be produced from crops that actually protect soils. Unfortunately, cellulosic ethanol is not yet commercially available, thus the nation must go from zero to 25 billion gallons cellulosic ethanol in ten years.
Cellulosic ethanol requires a lot of biomass and thus a lot of land. It would take approximately 306 million tons of cellulosic biomass to produce 25 billion gallons of ethanol."
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