California Multimedia Evaluation of E11-E15 Gasoline-Ethanol Blends

The California Health and Safety Code (CHSC) requires that a multimedia evaluation be conducted and reviewed by the California Environmental Policy Council (CEPC) before specifications for new motor fuels can be adopted by the California Air Resources Board. The purpose of the multimedia evaluation is to enable CEPC to determine whether a new fuel would create any significant new environmental or public health impacts.

In 1999, the State of California performed a multimedia evaluation regarding the use of ethanol in gasoline and approved the use of blends of up to ten percent ethanol in gasoline (E10). Today, virtually all gasoline sold in California is E10. In addition, based on action taken by the California Air Resources Board in 1992, eighty-five percent ethanol blends (E85) can be sold in California. Given that gasoline-ethanol blends have a long history of being used successfully in California and that ethanol is a renewable fuel with low carbon intensity, increasing the content of ethanol in blends with gasoline is one way in which California can make progress towards achieving its goals regarding greenhouse gas emissions. In addition, increased use of ethanol in blends with gasoline has a number of other potential benefits, including reduced dependence on petroleum.

At present, the most practical short-term approach to increasing ethanol use in California would be to approve the use of gasoline-ethanol blends above E10 up to 15 percent ethanol (E15). E15 has been approved at the federal level. U.S. EPA issued a waiver in 2010 approving the use of E15 in 2007 model year and newer light-duty vehicles. In 2011, U.S. EPA issued a second waiver extending the approval to 2001 model year and newer light-duty vehicles.

In light of the above, Growth Energy and the Renewable Fuels Association (RFA) have undertaken a multimedia evaluation for E15 gasoline-ethanol blends based on the addition of denatured fuel ethanol with California Reformulated Gasoline Blendstocks for Oxygenate Blending (CARBOBs) that are approved for use in producing E10 blends under the California Reformulated Gasoline Regulations for Model Year 2001 and newer California vehicles. This is intended to be the Tier 1 Report for those fuels.

The findings of the evaluation demonstrate approval of blends up to E15 will yield environmental benefits and decrease public health risks relative to a continuation of the current E10 limit. In summary, the potential for significant new environmental and public health impacts associated with gasoline-ethanol blends up to E15 has been generally well-examined and clearly documented. The evidence suggests environmental benefits and decreased risks associated with E15 relative to E10. Section 10 identifies the knowledge gaps that currently exist with respect to the potential impacts of increasing the ethanol content of California gasoline from 10 percent to 15 percent.