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3 min ago 2 min read
US lawmakers are pushing for regulatory changes that could open a larger domestic maritime market for bio-liquefied natural gas (bio-LNG).
In a letter to the Environmental Protection Agency (EPA), seven Republican members of the House urged the agency to expand the Renewable Fuel Standard (RFS) to include more vessels operating on US inland waterways and coastal routes.
The American Biogas Council (ABC) welcomed the move, saying it could create fresh demand for domestically produced bio-LNG and encourage investment in renewable fuel production and port infrastructure.
Under current rules, certain renewable fuels used in marine transport are excluded from RFS eligibility because of how the EPA classifies ocean-going vessels, including those equipped with Category 3 engines.
The lawmakers argue that this definition is too broad, as it can exclude vessels primarily operating within US waters simply because of their engine type.
They have asked the EPA to clarify which inland and coastal vessels qualify and narrow its definition of ocean-going vessels so renewable fuels used predominantly in domestic commerce can qualify regardless of engine category.
The RFS provides a financial incentive for renewable fuel production through tradeable credits, meaning wider eligibility for maritime fuels could improve the economics of bio-LNG supply and encourage investment in US production and liquefaction capacity.
“Expanding RFS eligibility would open an important new market for American-made bio-LNG and other renewable fuels,” said Patrick Serfass, Executive Director of ABC.
Serfass said bio-LNG would allow LNG-capable vessels to use a domestically produced renewable alternative while taking advantage of existing LNG infrastructure.
The lawmakers, led by Congresswoman Mariannette Miller-Meeks of Iowa, argued that the widened eligibility would encourage investment in US fuel production, port infrastructure, and vessel modernisation without new legislation or federal spending.
Their letter asked the EPA to prioritise the changes in its next RFS rulemaking, while preserving existing exclusions for marine residual fuel and Emission Control Area-compliant fuel.
The push comes amid in US renewable gas production. According to ABC, domestic renewable natural gas (RNG) output rose 24% in 2025 to 225.6 million MMBtu, while more than $2bn was invested in new biogas projects. Of the 70 new projects commissioned during the year, 68 were designed to upgrade biogas into RNG.
Growing US biogas production could also support (CO2) supplies, with CO2 separated during biogas upgrading potentially captured, purified and sold for industrial use rather than released into the atmosphere.
