Skip to content

Ernst, Grassley Push for Increased Renewable Fuel Standard Volumes

WASHINGTON – U.S. Senator Joni Ernst (R-Iowa) joined her colleagues in calling on Environmental Protection Agency (EPA) Administrator Michael Regan to raise Renewable Fuel Standard (RFS) volumes for biomass-based diesel and advanced biofuels to levels that are consistent with production and availability.

“America’s environmental and energy security depend on the widespread production, availability, and use of biofuels. Biofuels play a particularly critical role in emissions reduction for heavy-duty transportation — including aviation, shipping, rail, and trucking — while opening up economic opportunities for American farmers,” wrote the lawmakers. “A strong RFS and broad availability of homegrown agricultural feedstocks are critical for ensuring we keep up the progress we have made in decarbonizing our roads, seas, railways, and skies.”

“Since the volumes were set last summer, RIN values have decreased by an average of 66 percent, sending a discouraging market signal to farmers, feedstock producers, biofuel producers, blenders and investors,” the lawmakers continued. “Domestic fuel production facilities are closing as a result, putting Americans out of work and disrupting local economies. The negative signal to renewable fuel producers threatens billions of dollars of investment in feedstock and fuel production, including for Sustainable Aviation Fuel. Without EPA action, America will miss out on the carbon reductions delivered by advanced biofuels.”

The full text of the letter is available here.


Last year, before the EPA implemented the finalized blending volumes for 2023 through 2025, Ernst urged the agency to increase the proposed Renewable Volume Obligation (RVO) levels for advanced biofuels and biomass-based diesel fuels. Instead of listening to Ernst’s warnings, the EPA finalized blending volumes that failed to accurately reflect market conditions and future production capacity coming online. As a result, two biomass-based diesel plants have now closed, including one in Ralston, Iowa. Following the plant’s closure, Ernst pushed the administration to increase RVO levels for homegrown Iowa biofuels.

Ernst has consistently worked across the aisle to support and promote biofuels, Iowa farmers and producers, and the RFS. Learn more here.