A critique of lifecycle emissions modeling in “the greenhouse gas benefits of corn ethanol— assessing recent evidence”

Although recently published research addresses a range of issues relating to the corn ethanol lifecycle, much attention has focused on the result that corn ethanol production has a significantly better emissions profile than the U.S. Environmental Protection Agency (EPA) concluded in its 2010 regulatory impact analysis for the Renewable Fuel Standard. This working paper critically assesses this recent work and finds that the result is driven by a large reduction in the estimation of indirect land use change emissions outside the United States that is poorly supported and implemented. The authors discuss this and other issues in detail, including that recent papers paid more attention to evidence that could suggest lower lifecycle emissions compared to the EPA’s analysis than to evidence that could suggest the opposite.