A bipartisan group of 16 senators and 36 representatives on July 23 sent a letter to U.S. Treasury Secretary Janet Yellen urging her agency to take immediate action to finalize the rules to implement the 45Z clean fuel production credit. 

The letter encourages Treasury to publish proposed 45Z rulemaking, including any carbon models, and safe harbor guidance by Sept. 1 and complete the final rulemaking no later than Nov. 1. The lawmakers also urge Treasury to ensure that the 45Z credit is available only to domestic fuel producers and advise Treasury to use the U.S. Department of Energy’s GREET model to calculate greenhouse gas (GHG) emissions reductions, as required by statute, but to exclude the additional indirect effects that were added as part of the GREET model developed for the 40B sustainable aviation fuel (SAF) tax credit. In addition, the lawmakers ask Treasury to include a suite of climate-smart agriculture (CSA) practices without a “bundling requirement” and include a broader array of industrial decarbonization technologies, feedstocks and agricultural practices. 

“Lack of regulatory certainty is already putting thriving businesses at risk as fuel producers are unable to make important business decisions regarding their fuel,” the lawmakers wrote. “Capital investment remains uncommitted, threatening certain projects and expansion plans, including the administration’s stated goals to support new markets like sustainable aviation fuel (SAF) and low-carbon transportation fuels.

“To provide a clear market signal to the industry, the CSA rules included in the Section 40B GREET model must be revised for 45Z,” they continued. “Limiting the choices to just three CSA practices, when the U.S. Department of Agriculture (USDA) CSA and Forestry Mitigation Activities List for FY2024 includes over 50 practices and 100 activities, disincentivizes CSA investment. The ‘bundling’ requirement for farmers to adopt multiple CSA practices before getting credit for any single practice creates a barrier to entry and will exclude many acres of farmland. In 45Z, more CSA practices must be included and farmers must be permitted to adopt them in a practice-by-practice fashion without a ‘bundling’ requirement.”

Within the letter, the lawmakers also specifically identify some of the industrial decarbonization technologies, feedstocks and agricultural practices they think Treasury should address. This includes energy storage, combined-heat-and-power (CHP) technologies, mechanical vapor recompression, biomass-to-heat, advanced yeasts and enzymes, thermal vapor recompression, on-farm energy use reductions and biogenic and non-biogenic carbon capture and storage (CCS). The letter also encourages Treasury to recognize waste, solar and nuclear power sources along with additional biofuel feedstocks, such as sorghum, corn wet mills, additional oilseeds and corn kernel fiber. 

Clean Fuels Alliance America applauded the letter. “Clean Fuels applauds the bipartisan effort of Senators and Representatives to call for timely action from Treasury,” said Kurt Kovarik, vice president of federal affairs for Clean Fuels. “Biodiesel, renewable diesel, and sustainable aviation fuel producers are already annually producing nearly 5 billion gallons of advanced biofuels that could qualify for this credit. They need policy certainty immediately to make the transition to the producer credit and maintain growth in the industry.”

Growth Energy also welcomed the bipartisan push for swift action on the 45Z tax credit. “America’s biofuel producers and our farm partners stand ready to fast-track new investments in low-carbon fuels, but we need regulatory certainty to move forward,” said Growth Energy CEO Emily Skor. “We applaud Senator Ernst and all our rural champions in Congress for reminding the Treasury that swift implementation of 45Z based on the best available science is the key to unlocking exponential growth in rural America through the enhanced production of biofuels. We urge the administration to maximize the impact of the 45Z credit by signaling to the market that Treasury intends to follow Congress’ intent by recognizing and rewarding the full suite of carbon-smart practices happening at the plant and on the farm.” 

The letter is signed by Sens. Joni Ernst, R-Iowa; Tammy Duckworth, D-Ill.; John Thune, R-S.D.; Amy Klobuchar, D-Minn.; Pete Ricketts, R-Neb.; Tammy Baldwin, D-Wisc.; Tina Smith, D-Minn.; Mike Rounds, R-S.D.; Deb Fischer, R-Neb.; Debbie Stabenow, D-Mich.; Jerry Moran, R-Kan.; Richard Durbin, D-Ill.; Sherrod Brown, D-Ohio; Gary Peters, D-Mich.; Roger Marshall, R-Kan.; and Todd Young, R-Ind.; along with Reps. Brad Finstad, R-Minn.; Eric Sorensen, D-Ill.; Mariannette Miller-Meeks, R-Iowa; Nikki Budzinski, D-Ill.; David Scott, D-Ga.; Pete Stauber, R-Minn.; Michelle Fischbach, R-Minn.; Kelly Armstrong, R-N.D.; Donald Davis, D-N.C.; Elissa Slotkin, D-Mich.; Darin LaHood, R-Ill.; Dusty Johnson, R-S.D.; Zach Nunn, R-Iowa; Ashely Hinson, R-Iowa; Mark Alford, R-Mo.; Mike Flood, R-Neb.; Don Bacon, R-Neb.; Derrick Van Orden, R-Wisc.; Mark Pocan, D-Wisc.; Ann Wagner, R-Mo.; Mike Bost, R-Ill.; Adrian Smith, R-Neb.; Daniel Kildee, D-Mich.; Tracey Mann, R-Kan.; Rosa DeLauro, D-Conn.; Jake LaTurner, R-Kan.; Sam Graves, R-Mo.; Marcy Kaptur, D-Ohio; Max Miller, R-Ohio; Robin Kelly, D-Ill.; Jill Tokuda, D-Hawaii; Randy Feenstra, R-Iowa; Angie Craig, D-Minn.; Jimmy Panetta, D-Calif.; Ron Estes, R-Kan.; and Sharice Davids, D-Kan. 

A full copy of the letter is available on Ernst's website.