Top: A RNG fast-fill facility used by Amazon in Groveport, Ohio. Photo courtesy of Clean Energy Fuels Corp.

The federal budget reconciliation bill signed into law on July 4 includes a two-year extension of the Clean Fuel Production Tax Credit (Section 45Z), moving the sunset date from December 31, 2027, to December 31, 2029. In the Inflation Reduction Act, the credit was scheduled to sunset in 2031. This extension benefits anaerobic digesters (AD) upgrading biogas generated to renewable natural gas (RNG).

In another RNG development that affects digesters, the U.S. EPA proposed a rule in mid-June that establishes required Renewable Fuel Standard (RFS) volumes (known as renewable volume obligations or RVOs) and percentage standards for 2026 and 2027, as well as to partially waive the 2025 cellulosic biofuel volume requirement and revise the associated percentage standard due to a shortfall in cellulosic biofuel production. The proposed RVOs for cellulosic biofuels (sold as D3 RINs under the RFS) are 1.19 billion RINs in 2025, 1.3 billion in 2026 and 1.36 billion in 2027. EPA also proposed removing renewable electricity as a qualifying renewable fuel under the RFS program (eRINs). That pathway was never activated by U.S. EPA. The public comment period on the proposed changes ends August 8, 2025. Notes American Biogas Council Executive Director Patrick Serfass, “The ABC is disappointed by EPA’s proposal, which reduces the growth of cellulosic biofuels under the RFS. The proposed D3 RVO cuts growth in half, two years in a row, down to 5% annual growth, ignoring the demonstrated 20% to 30% growth of D3 fuel production.”