Federal environmental regulators recently set next year's proposed preliminary renewable fuel standard (RFS) volume plan, but renewable natural gas (RNG) proponents said they are not satisfied with it.

For the cellulosic biofuel category, the Environmental Protection Agency (EPA) volume for 2020 is 540 million gallons of ethanol gallon equivalents (EGE), an increase of 120 million gallons over this year's renewable volume obligation.

The total falls short of "accounting accurately both for volumes waived via small refinery exemptions and for actual real-world RNG production," said RNG Coalition CEO Johannes Escudero. He said the 29.2% increase recognizes ongoing RNG production growth, but it is not enough.

EPA set what it considers "conventional" renewable fuel, mostly corn-derived ethanol, at 15 billion gallons; advanced biofuel volumes for 2020 at 5.04 billion gallons; and biomass-based diesel volumes at 2.43 billion gallons for 2021. All the volumes are in EGE, except the biodiesel.

The EPA* estimated that RNG will total 525 million EGE, compared to its proposed overall draft allocation of 540 million EGE for cellulosic biofuels in 2020.

"Our data projections for the RNG versions of compressed natural gas and liquefied natural gas (LNG) used in transportation in 2020 under the RFS is currently quite a bit higher than the full 540 million EGE," said RNG Coalition spokesperson Marcus Gillette.

Escudero said, "We will work diligently with EPA throughout the public comment period toward a final rule later this year that reflects the full growth of the RNG industry and accounts for the impact of small refinery exemptions"

Last month, natural gas vehicle fueling pioneer Amp Americas completed a $41 million sale of its 20 fueling stations to American Natural Gas (ANG). Amp plans to concentrate on its RNG projects through its major Indiana-based biogas operations in Renewable Dairy Fuels.

"The company also will continue to invest heavily in dairy RNG projects and plans to break ground on two additional operations later this year," said CEO Grant Zimmerman. "This transaction gives us substantial runway for our next phase of growth and enables us to focus on our growing pipeline of dairy RNG projects."

Meanwhile, state lawmakers in Oregon and Ohio are joining other advocates to use alternative vehicle fuels in part to improve air quality.

Oregon Gov. Kate Brown was expected to sign legislation requiring heavy duty trucks to have model year 2007 equipment or newer by 2025. And In Ohio, higher taxes were assessed to gasoline and diesel based on a new transportation budget.

The Ohio measure included increased annual fees of $200 for alternative fuel vehicles and $100 for hybrid vehicles. NGV-fueled vehicles were not included.

"Unlike other alternative options, natural gas pays into the federal highway trust fund and into like funds in most states," said NGVAmerica President Dan Gage. The group supports states' effort to address air emissions, particularly from the goods-hauling truck and passenger-hauling bus fleets.

In other news, the International Maritime Organization is said to be considering a standard to clean up the high-sulfur content bunker fuel now in use, which could prompt a shift -- albeit small -- to using LNG as a fuel in marine vessels.

Advanced Clean Tech (ACT) Expo has speculated that most marine operators would turn to fuel that is less than 0.5% sulfur, and about 10% would install scrubbers and continue to use high-sulfur fuel.

"A smaller percentage will convert to LNG; as of now, there are only about 300 LNG vessels in operation or on order," said ACTExpo's Cliff Gladstein. "The remaining balance will either try blending or will attempt to evade compliance."

Elsewhere, San Diego Gas and Electric Co. has begun offering $850 credits on monthly electric utility bills to more than 21,000 electric vehicle (EV) drivers in the area. The number of EV drivers in the region has grown by 15,000 since 2017, a spokesperson said.

*Correction: In the original article, NGI mistakenly attributed next year's 525 million EGE volume for RNG estimate to the Coalition for RNG, when it should have been attributed to the U.S. Environmental Protection Agency. The RNG coalition's data projections for Renewable CNG/LNG fuel in 2020 under the national Renewable Fuel Standard is currently quite a bit higher than the full 540 million EGE (not just the EPA's 525 million EGE estimate). NGI regrets the error.