Corn stover is the above ground, non-grain portion of the corn plant. It is composed of lignocellulose material which can be converted to ethanol for use as a transportation fuel. A Life Cycle Assessment (LCA) of ethanol from corn stover is a cradle to grave evaluation of energy and environmental issues associated with the production, collection, and transport of corn stover, converting the corn stover into ethanol, and distributing and using the ethanol in cars and trucks. Corn stover ethanol LCAs frequently include an assessment of gasoline, the petroleum derived product that ethanol will displace, as a means to compare the two products.
A number of recent LCAs estimate that the use of ethanol produced from corn stover could decrease crude oil consumption and reduce greenhouse gas emissions for every mile driven compared to the use of gasoline. Greenhouse gas emissions for ethanol produced from corn stover are also less than for ethanol produced from corn grain. Compounds that cause smog, are a potential source of acid rain (i.e., nitrogen compounds), or cause dead zones in aquatic systems (i.e., nitrogen and phosphorus fertilizers) increase somewhat with the use of ethanol from corn stover relative to gasoline.