US’ first hydrogen passenger train ZEMU to debut this weekend
Posted: 12 September 2025 | Global Railway Review | No comments yet
San Bernardino’s ZEMU hybrid hydrogen-battery passenger train launches Saturday, offering zero-emission, zero-fare rides along the Arrow Corridor.


Credit: SBCTA
The US’ first hydrogen-powered passenger train, ZEMU, will begin service on Metrolink this Saturday 13 September, marking a major milestone in sustainable rail transport.
The train will first depart from the Metrolink San Bernardino Downtown Station at 10:32 am and run along the nine-mile Arrow Corridor of the San Bernardino Line throughout the day.
Pioneering cleaner, greener travel
ZEMU, short for Zero Emission Multiple Unit, is a hybrid hydrogen fuel cell-battery train developed over more than a decade by the San Bernardino County Transportation Authority (SBCTA). Meeting Federal Railroad Administration (FRA) requirements, the train produces only water vapour as emissions, providing a clean alternative to conventional diesel-powered trains.
Visually striking, ZEMU features a blue and white water-vapour-themed design wrapped around its two passenger cars and central power pack housing the hydrogen and battery system. Built by Swiss manufacturer Stadler, it arrived in San Bernardino in June 2024 and has undergone extensive testing to ensure compliance with Metrolink systems and FRA standards.
In August 2024, the California State Transportation Agency recognised SBCTA for its pioneering work in bringing the US’ first ZEMU passenger train online, creating a framework for other transit agencies to adopt similar zero-emission technologies.
As the transportation sector increasingly pursues sustainable solutions, ZEMU demonstrates how hybrid hydrogen-battery technology can transform regional commuting while reducing environmental impact.
“Historic day for SBCTA”
Ahead of its debut, SBCTA Board President Rick Denison said:
Saturday will mark a historic day for SBCTA.
ZEMU is proof of our commitment to improving regional 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.”
Public rides will be available from any Arrow Corridor station, with schedules posted at Metrolinktrains.com.
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