The US Environmental Protection Agency (EPA) is proposing to increase the volumes of biomass-based diesel and advanced biofuels to be blended under the Renewable Fuel Standard (RFS).

Under the proposal, the renewable volume obligation (RVO) of biomass based diesel would increase from 2.1bn gallons in 2019 to 2.43bn gallons in 2020, the National Biodiesel Board (NBB) said in a 26 June statement.

The advanced biofuel RVO – which included some biodiesels – would increase from 4.29bn gallons in 2018 to 4.88bn gallons in 2019.

But despite the proposal sending a positive message to the industry, the EPA’s granting of dozens of retroactive small refinery hardship exemptions had undercut volumes in previous years and could still have a negative impact on the coming year.

Kurt Kovarik, vice president of federal affairs at NBB, said EPA administrator Scott Pruitt had provided numerous waivers to petroleum refiners, releasing them from their blending obligations under the RFS.

The waivers had effectively reduced the overall RFS biodiesel volumes by 100M gallons (454.6M litres) in 2016 and 275M gallons (1.25bn litres) in 2017.

Kovarik said the NBB welcomed the proposal to increase biodiesel volumes after two flat years, but added that instability in the RFS caused by the EPA had done significant damage that could be compensated for through “consistent and predictable growth” in future volumes.

“As a candidate on the campaign trail, Donald Trump pledged he would support biofuels and the RFS. While this is just a proposal, we hope the administration is serious about growing biodiesel volumes and will fulfill the President’s promise to support and grow the RFS,” Kovarik said.

According to the NBB, the Trump administration’s actions on the RFS so far had been disappointing for both the biodiesel industry and US Midwest farmers, who had seen the commodity prices of their crops – including soyabeans – crash due to US trade policy.