Hydrogen Fuel Cells Power First Zero-Emission Passenger Train on Metrolink’s Arrow Corridor

Come September 13, 2025, the San Bernardino County Transportation Authority (SBCTA) is rolling out North America’s very first hybrid hydrogen fuel cells and battery-electric passenger train on Metrolink’s Arrow Corridor. Built by Stadler, the ZEMU (Zero Emission Multiple Unit) is a real game-changer for zero-emission technology in U.S. commuter rail — waving goodbye to diesel and steering us straight into sustainable energy territory.

Strategic Implications

This is more than just a new train — it’s a big step toward California’s ambitious decarbonization goals and a shining example of why industrial decarbonization in public transit makes sense. With the ZEMU on the tracks, SBCTA not only locks in federal and state dollars but also proves that these trains can beat diesel DMUs in cost efficiency. Plus, they’ve carved out a template with the Federal Railroad Administration that others can follow.

And let’s not forget: Stadler’s on-time delivery spotlights a booming appetite for hydrogen-powered fleets. Cities and private operators are already talking partnerships to set up on-site electrolysis and refueling stations, supercharging the rollout of hydrogen infrastructure and taking zero-emission technology nationwide.

Technical Snapshot

The magic behind ZEMU is pretty neat: it tucks hydrogen in onboard tanks, then its fuel cells mix that hydrogen with oxygen to crank out clean electricity — the only byproduct? A puff of water vapor. On top of that, a beefy battery pack snags energy from regenerative braking and kicks in extra juice when the train needs to sprint. The payoff is a whisper-quiet, ultra-efficient ride that ticks all of Metrolink’s safety and performance boxes without a trace of diesel exhaust.

Environmental & Community Benefits

For folks along the 9-mile Arrow Corridor, the switch to ZEMU is a breath of fresh air — literally. San Bernardino County wrestles with smog and traffic noise every day, but swapping out diesel engines means slashing greenhouse gases and particulates. And if you thought trains were noisy, get this: ZEMU cuts noise by about 50%, so suburban stations suddenly feel a lot more peaceful.

Looking Ahead

Once ZEMU’s been up and running, SBCTA will be swimming in real-world data on everything from reliability to fuel-cell longevity and upkeep costs. Those nuggets of info will be gold for other transit agencies plotting their next-gen fleets. We’re betting this pilot will kickstart a wave of investments in regional hydrogen production and a network of refueling stations — all thanks to the proof-of-concept right here in San Bernardino.

And don’t be surprised if federal infrastructure grants and California’s Clean Transportation Program funnel millions into rolling out ZEMU-style trains on lines from LA-Ventura up to Sacramento.

Key Takeaways

• This marks North America’s first-ever continuous passenger service of hybrid hydrogen fuel cells trains.
• With the FRA’s thumbs-up, the operational playbook is ready for others to pick up.
• Cleaner air and quieter rides are coming to neighborhoods along the route.
• As more data rolls in, the cost perks could really chip away at diesel’s Total Cost of Ownership.

About Stadler
Stadler is a Swiss trainmaker that’s all about cutting-edge, eco-friendly rail solutions. The ZEMU is its first hybrid hydrogen fuel cells and battery-electric train headed to the U.S., building on successful runs in Europe and Asia.