Renewable natural gas is a cost-effective fuel that can be used as a 100% substitute for, or blended with, conventional natural gas.
Renewable natural gas (RNG) is made from 100% renewable sources.
RNG is made primarily from organic waste, generated by a variety of sustainable and renewable sources, including wastewater treatment plants, food and green waste, landfills, dairies, farms, and forest management. It can also be produced as a byproduct of renewable hydrogen and sequestered CO2, a key strategy to store surplus renewable electricity.
Unlike fossil fuel, RNG is not formed by a geologic process and did not spend millions of years underground. RNG simply recycles carbon that is already present in the biosphere and does not add carbon to the atmosphere.
Using RNG enables fleets to go beyond carbon neutrality.
Because methane has up to 87 times the global warming potential of C02 in the first twenty years after its release, the immediate reduction of fugitive methane emissions is necessary to rapidly reduce the impacts of climate change. Producing natural gas from the organic waste source outlined above provides an unmatched opportunity to capture the methane – which is a greenhouse gas – that would have otherwise been emitted into the atmosphere through each source’s natural decomposition cycle.
The California Air Resources Board’s (CARB) assessment shows that RNG produced from dairy waste has one of the lowest carbon intensity (CI) rating of any transportation fuel. When made from renewable sources, natural gas for transportation can reduce greenhouse gas emissions up to 283%, with an average of 51% reduction (varies by feedstock).
Using RNG enables fleets to save money.
To expedite adoption of low carbon fuels, California created a comprehensive, verified, state-wide system—the Low Carbon Fuel Standard (LCFS) program. Since first implemented in 2011, low carbon fuel use is increasing and fuel producers in California are continuing to take action to decrease carbon intensity.
According to CARB’s LCFS data, more than 75% of natural gas used for transportation in California already comes from renewable sources. Fleet operators fueling with RNG can further lower their fuel cost via the financial credits afforded under the federal RIN Program and California’s LCFS Program.
The U.S. can produce large volumes of RNG.
As long as we have a productive society, we have the ability to capture and reuse methane emissions from organic waste at dairies, farms, wastewater treatment plants, and landfills.
A 2019 ICF study found that by 2040 there will be up to 32 billion diesel gallons equivalent (DGE) of RNG supply available nationally. Total on-road diesel use currently falls at about 46 billion DGE annually, meaning RNG could replace nearly 70% of the US’ on-road diesel fuel use annually.
- Getting to Neutral: Options for Negative Carbon Emissions in California, January 2020. https://www-gs.llnl.gov/content/assets/docs/energy/Getting_to_Neutral.pdf
- California Air Resources Board 2018 Low Carbon Fuel Standard Data
- American Gas Foundation, December 2019, Renewable Sources of Natural Gas: Supply & Emission Reduction Assessment Study. https://www.gasfoundation.org/wp-