Growth Energy, American Farm Bureau Federation, National Biodiesel Board, National Corn Growers Association, National Farmers Union, and the Renewable Fuels Association sent a letter to the US Senate Committee on Finance and the US House of Representatives Committee on Ways and Means outlining its recommendations for a sound and effective sustainable aviation fuel (SAF) tax credit.

In an effort to decarbonize transportation and reduce aviation emissions, Congress is considering new legislation to establish a tax credit to promote and develop robust domestic SAF production. To be successful, the ag and biofuels coalition notes in their letter, the tax credit must be based on accurate carbon accounting in life cycle analysis (LCA) led by the US Department of Energy:

Numerous members of our respective organizations are poised to produce SAF or sustainable feedstocks for SAF. Many others are looking to work toward participation in the full value chain in the relatively near future. We recognize the importance of decarbonizing the aviation sector with low carbon liquid fuels. Because biomass feedstocks are essential SAF sources, it is imperative that the tax credit properly account for the lifecycle emissions of these sources and the petroleum products these new fuels will replace.

We urge you to make the US Department of Energy (DOE) the lead agency in establishing a regularly updated LCA for any SAF credit. Across our federal government, DOE has the best resources, expertise, and current ability to assess lifecycle emissions fairly and scientifically.

The letter also pointed out that carbon intensity estimates under the International Civil Aviation Organization (ICAO) for some SAF sources are “wildly inaccurate and incorrectly penalized” and cannot be supported.

The ICAO methodology does not use the most comprehensive modeling approaches or most recent data for some important SAF production pathways, with some data more than a decade old. Therefore, carbon intensity estimates under ICAO for some SAF pathways are inaccurate and inappropriately penalized. Although various bills allow the option for DOE to be involved in conducting LCA with EPA, the language continues to require any U.S.-based LCA to be “as stringent as” the ICAO model. The meaning of “stringency” is ambiguous here, but we are concerned this language could be interpreted to require the use of the ICAO methodology in lieu of DOE’s more robust data and modeling approach.

Unlike the DOE, EPA does not maintain a regularly updated LCA model or methodology for biofuels. Notably EPA’s most recent comprehensive analysis for biofuels was conducted in 2009. EPA’s analysis does not reflect or capture the continuous improvement that has been witnessed over the past decade in biomass production or the technology and efficiency improvements in fuel production. As climate-smart agriculture practices continue to improve and expand and as new fuel production technologies for SAF are developed and scaled to market, a regularly-updated LCA is essential to the success of a SAF tax credit and its ability to incentivize new fuels and reduce emissions.

Along the same lines, the LCA for petroleum jet fuels must also be based on the most recent and accurate data to ensure a fair comparison is made between fuels. To ensure clarity, we recommend that Congress designate a baseline carbon intensity value for fossil jet fuel.