SAN BERNARDINO, Calif. — San Bernardino County’s transportation agency is making history with the launch of North America’s first hydrogen-powered passenger train.
The San Bernardino County Transportation Authority (SBCTA) will begin service Saturday, Sept. 13, for its new hybrid hydrogen fuel cell electric train, known as the ZEMU, which stands for Zero Emission Multiple Unit. The first train will depart the San Bernardino Downtown Metrolink Station at 10:32 a.m. and will make stops at five stations along a nine-mile route between San Bernardino and Redlands. Service will continue throughout the day, with rides free to the public on opening day.
The ZEMU train uses a combination of hydrogen fuel cells and battery technology to power both its propulsion and electrical systems. Its only emission is water vapor, making it one of the cleanest public transportation options available. SBCTA officials say the technology will help reduce air pollution and traffic in the Inland Empire, a region that continues to face some of the nation’s worst air quality.
“Saturday will mark a historic day for SBCTA,” Board President Rick Denison said in a statement. “ZEMU is proof of our commitment to improving air quality, embracing innovation and expanding clean-air transit options throughout the county. I look forward to riding ZEMU and am excited for residents and visitors to experience this train firsthand.”
The new train, built by Swiss manufacturer Stadler, arrived in San Bernardino in June 2024 and has since undergone months of testing to meet all Federal Railroad Administration standards and Metrolink system requirements. The ZEMU model is part of Stadler’s FLIRT H2 series — short for Fast Light Intercity and Regional Train — which is designed to operate using hydrogen fuel cells instead of diesel.
SBCTA partnered with Air Liquide Hydrogen Energy U.S. to build and install the hydrogen refueling system at the Arrow maintenance facility in San Bernardino. The FLIRT H2 can reach speeds up to 81 mph and recover energy during braking. It is also designed to operate in temperatures as high as 120 degrees Fahrenheit. The train can seat 108 passengers, with additional space for standing riders.
In August 2024, the California State Transportation Agency recognized SBCTA for its work in developing and deploying the ZEMU — the first of its kind in the nation. Officials said the project serves as a model for other transit agencies interested in adding zero-emission trains to their fleets.
The ZEMU’s design features a blue and white color scheme with a stylized water vapor motif, reflecting its clean energy source. The central “power pack” houses the hydrogen and battery propulsion systems.
SBCTA leaders say this launch represents a key step toward the agency’s long-term goal of operating a fully zero-emission fleet. The county initially began with low-emission diesel units, but contracts with Stadler will gradually replace those trains with ZEMU models over the next several years.
Metrolink’s Arrow service, which connects San Bernardino and Redlands, first began operations in October 2022. The addition of the ZEMU train marks a major upgrade for the line and a milestone for environmentally friendly transportation in Southern California.
Riders can find station details and departure times on Metrolink’s website.
The author thanks Spencer Booker, an MA student in Professor Taofeeq Adebayo’s research group at CSUSB, for his editorial support.