Abstract

As shortages of fossil energy, especially oil and natural gas, become evident, the United States has moved to convert corn grain into ethanol with the goal to make the nation oil independent. Using more than 20% of all U.S. corn on 15 million acres in 2007 was providing the nation with less than 1% of U.S. oil consumption. Because the corn ethanol project has been a disaster, there is growing interest to develop cellulosic ethanol. Wood, grasses, and crop residues are being proposed as sources for ethanol fuel. Though it may seem beneficial to use renewable plant materials for biofuel, the use of crop residues and other biomass for biofuels raises major concerns about energy balance, food security, and environmental problems.