California Air Resources Board (CARB) Q2 2020 data has confirmed that the energy weighted carbon intensity (CI) value of California’s natural gas vehicle fuel portfolio in the Low Carbon Fuel Standard (LCFS) program was below zero—at -0.85 gCO2e/MJ. This is the first time that any low carbon fuel portfolio has achieved a carbon-negative status since the program began.
“Given the large and growing volume of heavy-duty natural gas vehicles already hard at work on California’s roads, this is an extremely significant milestone,” said Todd Campbell, chair of the California Natural Gas Vehicle Partnership (CNGVP) and vice president of public policy and regulatory affairs, Clean Energy. “Both the short- and long-term climate benefits of this achievement are extremely significant. When combined with the fact that most natural gas vehicles recently placed into service are powered by near-zero emission engines, the natural gas vehicle industry is providing the most substantial and cost-effective contributions towards California’s goals to reduce criteria and greenhouse gas emissions while eliminating the use of diesel in favor of renewable, low carbon fuels.”
California’s LCFS, which measures the climate impact of various motor vehicle fuel pathways, is a market-based incentive program designed to decrease the carbon intensity of California's transportation fuel and instead provide a range of low-carbon and renewable fuel alternatives, reducing petroleum dependency and achieving air quality benefits. The “carbon intensity” of any given fuel measures all greenhouse gas emissions associated with the entire life cycle of a transportation fuel including production and consumption. Transportation fuels with low—or even negative—carbon intensity scores are better for the environment as they produce less climate-altering greenhouse gas emissions.
Renewable natural gas (RNG)—which is produced by capturing and processing the methane emitted from organic sources including dairy waste, wastewater treatment plants, food and green waste, landfills, and forest management—has the lowest carbon intensity rating of all fuels in the CARB LCFS program. Many forms of RNG, such as that produced from food and green waste, have a carbon-neutral and even a carbon-negative rating. Other forms of RNG, such as that produced from dairy waste, can have carbon intensity ratings that are 200 to 300% lower than even a battery-electric vehicle powered by renewable energy such as solar or wind.
The most recent data from CARB’s LCFS program also confirms another significant milestone—RNG made up nearly 90% of natural gas vehicle fuel in the program and consumed in California in the first half of 2020. Looking ahead, both the volume and carbon intensity benefits of RNG consumed by California will continue to grow. More than one billion dollars of investment is currently taking place in California to develop a wide array of in-state RNG production projects. As California continues to source increasing amounts of transportation-grade RNG from projects with carbon negative sources, such as dairy biogas, the average carbon intensity of California-produced RNG will only continue to improve.
Gladstein, Neandross & Associates (GNA), a California-based clean transportation and energy consulting firm, recently released a study which forecasts that, by January 2024, California-produced RNG for transportation will have an average energy-weighted carbon intensity of -101.74 gCO2e/MJ, generating 3.4 million tons of GHG reductions annually. At that negative carbon intensity, an average natural gas vehicle fueled by California RNG will completely offset the GHG emissions of two diesel trucks.
“As long as we have a productive society, we will continue to generate organic waste that has the potential to produce methane,” said Cliff Gladstein, founding president of Gladstein, Neandross & Associates and a key author of the study. “Harnessing these methane emissions to produce RNG for transportation fuel enables us to immediately and cost-effectively reduce the impacts of climate change.”
RNG can be used as a seamless, drop-in replacement for conventional natural gas in transportation. Additionally, due to the financial incentives available through programs including the LCFS, RNG can be purchased at a price on par with—or lower than—the price of diesel, based on the CI.
“We are thrilled to see the growing use of low carbon renewable natural gas by our customers in California and across the U.S.,” said Tom Swenson, vice-chair of the California Natural Gas Vehicle Partnership and business development manager for Cummins Inc. “Fleets are increasingly interested in taking real and immediate actions on climate change and local air quality. This one-two punch of renewable natural gas in an ultra-clean engine allows fleets to achieve cost-effective carbon-negative operations right now in a vehicle that meets their operational requirements.”
Fleets across the country have been successfully using natural gas vehicles for more than two decades. Today, more than 175,000 natural gas vehicles are on U.S. roads. Near-zero natural gas trucks and buses are commercially available from more than 50 different vehicle manufacturers—including Autocar, Bluebird, El Dorado National, Freightliner, Gillig, Kenworth, Mack, Peterbilt, Thomas, Tico, Volvo and others. With these well-established brands also come robust sales and service networks, as well as an expansive public fueling network dispensing renewable natural gas.
“With a strong foundation in place, CNGVP members look forward to working with Governor Newsom, CARB, California Energy Commission, local California air districts, the Biden Administration and the federal government to further build upon these extremely important successes,” added Campbell. “With smart policies, we have the ability to significantly scale up these short- and long-term emission benefits, while providing an economically sustainable alternative fuel option to customers, simultaneously driving in-state investment in circular economies at the local level; it’s a win-win-win-win opportunity.”
