RFA: Greenhouse Gas Analysis of Ethanol Outdated

Group says EPA's estimate should take into account new science, studies

Published on: Dec 4, 2012

A Renewable Fuels Association letter sent Friday to EPA Administrator Lisa Jackson requested that the Environmental Protection Agency immediately initiate a process to update its obsolete lifecycle greenhouse gas analyses of corn and sugarcane ethanol for the Renewable Fuel Standard.

"There have been literally dozens of new studies and modeling improvements since EPA finalized the RFS2 almost three years ago," Dinneen said. "Overwhelmingly, these new reports and data show that the corn ethanol process is far less carbon intensive than assumed by EPA. Corn ethanol is offering real and significant GHG savings today."

Dinneen also said recent research shows that the lifecycle GHG emissions associated with Brazilian sugarcane ethanol production are worse than originally estimated by EPA for the RFS2. Harvested sugarcane area in Brazil has expanded 55% since 2006, with at least 70% of that expansion occurring on previous pasture land, research shows.

Group says EPAs estimate should take into account new science, studies
Group says EPA's estimate should take into account new science, studies

The RFA letter summarizes the results of recent studies showing that EPA overestimated ethanol plant energy use, corn farming energy use, and land use change emissions.

"Indeed, improved modeling and better data show that the corn ethanol process is more efficient and producing less GHG emissions today than EPA assumed would be the case in 2022," the letter states.

When modeling and data improvements are combined into one analysis, as was done in a recent paper by researchers at Purdue University and the Department of Energy, corn ethanol, on average, reduces GHG emissions today by at least 24% compared to gasoline even with speculative LUC emissions included.

Dinneen said it is imperative that EPA recognizes this new science and data for several reasons.

"EPA has been a leader in the field of biofuels lifecycle assessment, and initiating a process to update the RFS2 analysis ensures that the Agency maintains an active and relevant role in the scientific discussion around biofuel lifecycle GHG accounting," he wrote. "Second, an effort by EPA to update its analysis will enhance the public's understanding of corn ethanol's lifecycle GHG impacts and serve to inform debate on future biofuels policies. In addition, updated analyses of corn and sugarcane ethanol will allow for fairer comparisons of the two fuels moving forward. Finally, updating EPA's analysis would help ease the Agency's workload and reduce the backlog of petitions for new pathways."