DOE Updates 45ZCF-GREET Model for Clean Fuel Tax Credit: Key Changes and Industry Impact

The U.S. Department of Energy released an updated 45ZCF-GREET model on June 12, 2026, which is used to calculate carbon intensity for the 45Z clean fuel production credit. The update removes indirect land use change penalties for American biofuels, aligns with the One Big Beautiful Bill Act, and restricts feedstock eligibility to the U.S., Mexico, and Canada. It also adds new pathways for renewable natural gas and updates data for all fuel pathways. Industry groups like Growth Energy and the Renewable Fuels Association welcomed the update, saying it provides certainty for ethanol and biodiesel producers. The model is one of three key pieces of 45Z guidance still needed, with USDA feedstock rules and final Treasury regulations pending. The update allows producers to calculate tax credits for the current tax year, supporting domestic energy production and farm income.