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Renewable natural gas’ one-two punch against emissions — Net-Zero Carbon

Clean Energy VP expects ‘very rapid growth of RNG’ in coming years

(Image: FreightWaves)

On this episode of Net-Zero Carbon, Tyler Cole, director of carbon intelligence at FreightWaves, chats with Greg Roche, VP of sustainability at Clean Energy Fuels, about the future of renewable natural gas (RNG).

RNG is produced from methane captured from sources of organic waste, such as dairy farms, animal feedlots, food waste or landfills. If not captured, that methane goes directly into the atmosphere and has a global warming potential impact 28 times more powerful than carbon dioxide, Roche said.

“You basically get a two-for-one benefit in the world of carbon accounting. You get a lot of benefit from eliminating methane, and you get a lot of benefit from driving trucks with clean fuel,” Roche said.

He and Cole discussed how the widespread availability of natural gas pipelines across the country, along with Clean Energy’s (NASDAQ: CLNE) many fueling stations, are making it easy to expand the use of RNG.


“We know the future is bright because we feel the tailwinds continuing to blow this decarbonization of transport forward. I think the next decade is going to be full of tons of momentum, so to have that infrastructure in place already is just a boon to you guys,” Cole said.

Roche said RNG’s average carbon intensity is negative in California, while diesel’s is about 100. 

More companies are making sustainability commitments and net-zero emissions goals, but they are still looking for solutions to get there. Powering facilities with 100% renewable energy is helpful, but net-zero emissions have to extend to a company’s vehicles as well.

Because RNG in California is a carbon-negative fuel, switching potentially just 25% of a company’s fleet to RNG could offset the emissions of its entire fleet, according to Roche.


Read: Clean Energy’s renewable natural gas to power an additional 611 trucks

RNG potential, other alternative fuels

RNG could replace up to 75% of trucks and buses running on diesel in the U.S., he said. “That’s pretty impressive.”

“In 2020, 53% nationally of the natural gas fuel dispensed in America was RNG,” Roche said.

Cole and Roche agreed that no alternative fuel will replace diesel by itself, but a combination of RNG, battery-electric and fuel cells could potentially accomplish it. And the supply chain, infrastructure, manufacturing and carbon benefits of using RNG have already been built out and proven.

Roche said that RNG permits and early stage projects are starting to penetrate into every state in the U.S. Because of the way the regulations and credits favor RNG more in California, it will see more RNG. But there’s a lot of overflow into other states, especially those that are pursuing their own low-carbon standards.

“You’re going to see a very rapid growth of RNG supply around the U.S. … There’s going to be a lot of new production coming online,” Roche said.

View all of FreightWaves’ Net-Zero Carbon episodes and sustainability stories.

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Alyssa Sporrer

Alyssa is a staff writer at FreightWaves, covering sustainability news in the freight and supply chain industry, from low-carbon fuels to social sustainability, emissions & more. She graduated from Iowa State University with a double major in Marketing and Environmental Studies. She is passionate about all things environmental and enjoys outdoor activities such as skiing, ultimate frisbee, hiking, and soccer.