As 40B GREET Deadline Looms, RFA Offers Recommendations for SAF Emissions Modeling

In a letter submitted to the Biden administration today, the Renewable Fuels Association laid out recommendations for ensuring that the best available science and data are used in determining eligibility for the sustainable aviation fuel (SAF) tax credit established in the Inflation Reduction Act. The Treasury Department released guidance in December regarding the implementation of the credit, and the administration committed to releasing an updated version of the GREET model by March 1 for use in estimating the lifecycle greenhouse gas emissions of SAF.

“One of the most promising forms of SAF involves the conversion of ethanol to jet fuel,” wrote RFA President and CEO Geoff Cooper. “Ethanol has key advantages as a feedstock for SAF, as it is cost-competitive with petroleum-based fuels and is by far the largest-volume biofuel produced in the U.S, with output of nearly 16 billion gallons per year.”

The letter was sent to an interagency working group (IWG) that includes USDA, EPA, DOE, and FAA. It contained detailed comments and recommendations, including analysis of the strengths and weaknesses of different modeling tools, methodologies, and data sets being considered by the IWG for inclusion in the soon-to-be-updated “40B GREET model.” The letter also encouraged the IWG to ensure the new model is informed by actual observations and empirical data from the post-2005 period of biofuel expansion. The updated modeling framework should also take a practical approach to integration of climate-smart agriculture practices, RFA’s letter says.

“In order for the full potential of the IRA to be realized, it is imperative that the proper lifecycle analysis modeling framework be adopted by the Treasury and IRS,” the letter concludes. After slight modifications are made by the IWG to include more current data and information, “…the resulting 40B GREET should be determined to satisfy the CAA section 211(o)(1)(H) criteria.”