A multi-state coalition of biofuel and farm advocates asked the Treasury Department to swiftly resolve any questions standing in the way of scaling up U.S. production of Sustainable Aviation Fuel.

Biofuel supporters urged the administration to quickly adopt the U.S. Department of Energy’s GREET model for calculating SAF tax credits under the Inflation Reduction Act. That would complete a process that was supposed to conclude by March 1.

“We are disappointed the administration didn’t fulfill its commitment to release a modified GREET model by March 1, but we appreciate the importance of getting the modeling right,” wrote 26 organizations. “At the same time, we caution against contradictory changes to GREET that would stack unwarranted penalties on agricultural feedstocks, cut rural America out of a promising green energy market, and undermine any path to achieving SAF goals.”

Groups in the coalition include Clean Fuels Alliance America, Growth Energy, and many others.