The greatest obstacle to widespread use of cellulosic ethanol is the cost of its production. Until engineers refine the process, cellulosic ethanol costs more to produce than gasoline, and even more than corn ethanol. Another concern is that poorer countries will clear-cut their forests to sell the plant material for cellulosic ethanol production. There's even worry that farmers in developed countries will stop growing food on land to grow nonedible plant materials that can be made into cellulosic ethanol.
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