A comparison of corn-based ethanol with cellulosic ethanol as replacements for petroleum-based fuels: a review

This study reviewed the literature on corn and cellulosic ethanol for their potential to replace petroleum fuels. Metrics include: energy yield, cropland requirements, and pollution reduction. The key findings are that an agreement exists among the literature that corn production yields are insufficient to warrant large-scale production. The required cropland is far in excess of the available corn cropland. Furthermore, the use of corn for ethanol fuel will lead to continued increases in food prices worldwide. When these findings are considered along with the marginal improvement in CO2 emissions and other pollutants, it is apparent that corn ethanol is not viable for replacing petroleum fuels. In contrast, this study found that cellulosic ethanol, which can be grown on marginal cropland, provides a much greater energy yield and a significantly greater pollution reduction. In summary, cellulosic ethanol could provide one alternative to petroleum fuels and is deserving of large-scale test experimentation to conclusively demonstrate viability.

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