(June 17, 2010)  Sacramento, CA   – A new analysis of the inputs and modeling done on lifecycle carbon emissions for ethanol by both the U.S. Environmental Protection (EPA) and the California Air Resources Board (CARB) concludes that the similarity in the magnitude of the land use change emissions outcomes from the two analyses is “coincidence” rather than scientific consistency.

“The fact EPA and CARB arrived at similar indirect land use penalties for ethanol is pure happenstance, not proof of scientific convergence,” said Renewable Fuels Association Vice President of Research Geoff Cooper. “A close examination of the two analyses shows that it was coincidence not science that the estimates ended up being close. The modeling approaches, key assumptions and inputs used by the two agencies varied widely, highlighting the continuing lack of scientific consensus on how to model the carbon footprint of biofuels.”

As the report, conducted by Air Improvement Resource, notes, “…the land use emissions values from both analyses appear to be similar. However, the modeling systems, modeling inputs, and data used are quite dissimilar. Thus, this apparent alignment is mostly a coincidence, and to make improvements in land use modeling, these differences need to be clearly understood.”

The release of the analysis comes at time when new science has shown both agencies have grossly overestimated the indirect land use change (ILUC) penalty assigned to grain-based ethanol. Last month, research from Purdue University demonstrated that CARB overestimated the ILUC penalty for ethanol by a factor of two.

Additionally, survey data recently published in the journal Biotechnology Letters found dramatic reductions in ethanol’s use of process fuel energy (such as natural gas) and water, while ethanol yields have increased. Also, scientific findings to be published in the Proceedings of the National Academy of Sciences finds that improvements in agricultural production and efficiency have resulted in tremendous greenhouse gas savings over the past few decades.

On June 16, the RFA met with CARB staff to discuss this latest round of new scientific research and encouraged CARB to adopt this best available science. RFA is also participating in today’s Expert Working Group discussion.

“We feel that CARB has committed itself to using the best available science, so we want to ensure that new and improved data is integrated quickly and efficiently into their program,” said Cooper. “By incorporating these new findings into its modeling framework, grain-based ethanol would be allowed to play a role in the program for a longer period of time. However, to be perfectly clear, the RFA still believes the inclusion of indirect emission penalties against biofuels and not petroleum is both unfair and scientifically unjustified.”

The report addresses a number of findings of both EPA and CARB that appear to be similar, but further analysis demonstrates otherwise. In addition, the analysis notes that no scientific consensus yet exists on this issue. As the RFA noted above the analysis details, new science is constantly emerging.

“…the land use values being developed by researchers are in a constant state of flux. A paper by [Timothy] Searchinger and others originally estimated the corn ethanol LUC impact at 103 g/MJ. For the final LCFS rule, CARB estimated 30 g/MJ for the average of seven scenarios. For the Renewable Fuel Standard proposed rule, EPA estimated 63 g/MJ. For the final rule, EPA estimated LUC emissions at 28 g/MJ. Finally, a recent paper by Purdue researchers utilizing an improved version of the GTAP model estimates a value of 14 g/MJ.”