The long-term future of emission standards is still up in the air after President Donald Trump’s election to the Oval Office, but the trucking industry continues to work toward better efficiency and lower emissions.
And while the emissions mandates that were looming over the entire vehicle industry have been stopped — at least for now — there’s no denying that viable, more eco-friendly alternatives are needed.
While battery electric motors have been the primary focus of manufacturers and government agencies, renewable diesel, hydrogen and natural gas are also on the radar.
With that in mind, it’s a great time to check out alternatives to traditional diesel fuel.
ICE technology evolving
Strides are being made in the field of internal combustion engines (ICEs) powered by alternative fuels.
In an unveiling by Cummins executives in August 2024, the Cummins X15 engine was touted as a platform that would be a force for alternative fuels. The X15 series has three models — including one for advanced diesel, natural gas and hydrogen. The goal is to achieve peak performance over the long haul, which includes increased fuel economy, lower emissions and more time on the road.
“I think a lot of what we are trying to do … is improve the overall CO2 performance of the engine, make the engine lighter,” said Tom Marsh, who serves as Cummins VPI leader for the X15. “Improve in all of those areas, but at the same time, maintain the robustness of the product, but also adopt the global platforms.”
Field testing shows promising results
In July 2024, Allison Transmission announced a partnership with Cummins to test and validate the new Cummins X15N 15-liter natural gas engine paired with the Allison 4000 Series fully automatic transmission.
Sandman, a bulk-cement hauling fleet based in San Jose, California, successfully completed over 50,000 miles of vehicle testing in the field and reported significant improvements in fuel efficiency and performance.
According to press reports, the test vehicle — a Peterbilt tractor equipped with the X15N engine and Allison 4000 series transmission — demonstrated “impressive” performance and productivity.
Victor Landaverde, fleet manager for Sandman, describes the 50,000-mile field testing of the natural gas-powered tractors as “flawless,” noting that the company’s drivers haul 80,000-pound loads through stop-and-go traffic between San Jose and San Francisco multiple times each day. He also says the fleet of more than 100 trucks achieved “excellent” fuel efficiency.
“As the industry continues to evaluate electric vehicle technology and works to overcome the hurdles facing this technology adoption, more customers are expected to adopt alternative fuel engines as a solution to meet increasing emissions stringencies,” Landaverde said.
Alternative fuel infrastructure progresses
Infrastructure for natural gas is also starting to emerge with Clean Energy as its leader.
In 2024, Clean Energy Fuels Corp. announced a significant increase in its renewable natural gas (RNG) footprint as it opened two additional stations in San Bernadino and Perris, both in Southern California.
“There’s a growing realization that the other much-hyped technologies aren’t living up to their promises of availability, fueling infrastructure or cost of ownership,” said Chad Lindholm, senior vice president at Clean Energy. “The RNG solution is here and now, providing fleets with incredible emissions reductions affordably.”
Clean Energy manages more than 600 stations throughout the U.S. and Canada, 200 of which provide tractor-trailer access.
In addition, travel stops — including Loves, Travel Centers of America, Pilot and others — are working to integrate alternative fuels into their sites.
According to the U.S. Department of Energy (DOE), hydrogen, when used in a fuel cell to provide electricity, is a zero tailpipe emissions alternative fuel produced from diverse energy sources. Currently, drivers of light-duty fuel cell electric vehicles (FCEVs) can fuel up at retail stations in less than five minutes and obtain a driving range of more than 300 miles.
Research and commercial efforts are under way to expand the limited hydrogen fueling infrastructure and increase the production of FCEVs in the freight industry.
While battery-electric fuel cells may be the future of freight, that future is not now, say most stakeholders in the trucking industry. The tried-and-true ICE remains king, and innovations in fuel and engine production are making it more eco-friendly as well.
This story was published in the March/April 2025 edition of Truckload Authority magazine, the official publication of the Truckload Carriers Association (TCA).
Bruce Guthrie is an award-winning journalist who has lived in three states including Arkansas, Missouri and Georgia. During his nearly 20-year career, Bruce has served as managing editor and sports editor for numerous publications. He and his wife, Dana, who is also a journalist, are based in Carrollton, Georgia.
