Hydrogen’s Humming in Power Generation

Hydrogen fuel cells and combustion engines gain momentum in stationary power applications where infrastructure and regulations offer more flexibility.

August 8, 2025

Ryan Gehm

MTU hydrogen cogeneration units employ hydrogen engines with an output of 1 MW each that were adapted from MTU’s gas engine platform. (MTU)

Not long ago we covered some high-profile struggles hydrogen-technology companies had encountered, including Nikola and Hyzon both deciding to cease operations. But despite legitimate challenges, many OEMs and suppliers continue development efforts, confident that hydrogen – be it in combustion engines or fuel cells – will eventually make its mark on the industry.

Rehlko’s 1-MW fuel cell generator utilizing Toyota’s HFC modules can be designed and manufactured to the same operational standards as conventional generators. (Rehlko)

One segment where this is coming closer to reality is power generation in stationary applications.

Toyota of course is known for its hydrogen fuel cell (HFC) systems powering its passenger cars and Class 8 trucks built with Kenworth. Toyota is moving out of the pilot phase with Class 8 trucks and beginning to introduce production-level to its own logistics fleet, running routes from the Port of Long Beach to Toyota’s North American Parts Center in Ontario, California, and as far south as San Diego, according to Hannah White, fuel cell integration engineer at Toyota Motor North America (TMNA).

“Eventually, the end goal is to do long-range across the U.S. once we can get the infrastructure built up to support that,” she said during SAE International’s Sustainable Transportation Summit 2025 held online in July.

Lesser known, perhaps, is Toyota’s focus on stationary power – “another really great application that hydrogen is perfect for,” White said. “Data centers use a lot of power, they need a lot of backup power, and hydrogen is a great way to store energy and to become that backup generator in a clean way.”

“The beauty of stationary power for hydrogen is it’s completely silent, completely odorless,” she said, referencing a 50-kW unit built in collaboration with Toyota Racing Development that was used at an LPGA tour event in Palm Springs. “You wouldn’t even know that it’s there if you walked by. I see a strong future for applications like this for hydrogen.”

Toyota has developed a 1-MW stationary power unit as a proof-of-concept. “It’s not production-level – yet,” White said. The unit is currently located at NREL’s Flatirons campus in Colorado. “They’re developing a full renewable, sustainable grid using excess water and solar to then generate hydrogen with an electrolyzer,” she explained. “That electrolyzer can then produce power that can be turned back into electricity using this 1-MW generator. It’s a full circle moment.”

TMNA also recently announced an agreement to provide its HFC modules to Rehlko for use in stationary power generator products to satisfy growing interest in alternative fuels for stationary applications, including both backup and primary uses. The 1-MW fuel cell generator can reportedly be designed and manufactured to the same operational standards as conventional generators.

Rehlko and Toyota’s first collaboration involved developing and installing a 100-kW HFC power generation system to reinforce and back up the electrical infrastructure at a hospital in rural Washington State. They now have developed and engineered a commercialized 1-MW system to meet the demand for 1 MW or more, with Rehlko developing the overall system.

H2-ICE heating up

Hydrogen combustion engines are also getting in on the act. For example, two MTU hydrogen cogeneration units are being used in the Port of Duisburg, Germany, with each hydrogen engine having an output of 1 MW.

MTU gas engines were used as the basis and adapted to accommodate hydrogen. Modifications are made to the injection system, cylinders are redesigned, and a new control system is employed. The turbochargers are also replaced by new larger ones developed by Rolls-Royce so they can compress “considerably more air.”

Hydrogen dual-fuel use cases in gensets are being explored in field tests. (Volvo Penta)

Taking more of a phased approach, Volvo Penta offers a hydrogen dual-fuel engine built on its D8 EU Stage V platform that is suitable for off-highway segments like port handling but also for stationary applications such as gensets. “We have a D8 multifuel hydrogen ICE genset that we are offering in the market,” Anna Müller, president of Volvo Penta, said at a press conference at Bauma 2025. “So that means you can use hydrogen and/or diesel or HVO in a certain mix in that engine. That is a steppingstone into becoming fully zero emission.”

Early trial data has reportedly revealed a reduction of up to 80% in CO₂ emissions with the dual-fuel D8 engine, which is equipped with CMB.TECH’s dual-fuel system. Hydrogen is released from storage tanks and brought to low pressure, then injected into the engine’s air intake. Aspiration of hydrogen reduces the amount of diesel required to produce the same amount of energy from combustion, Volvo Penta says. If the hydrogen supply runs low, the engine can operate entirely on diesel or HVO.

Another promising application could see hydrogen gensets increasingly employed to power EV charging infrastructure. (SAE’s Sustainable Transportation Summit 2025 detailed one example: INNIO’s Jenbacher engine supporting a 1-MW hydrogen-powered EV charging system.) Because stationary applications are subject to different regulations compared to off-highway vehicles, that may allow for more flexibility in the adoption of alternative energy solutions.

Hydrogen still has its hurdles, but in stationary power it’s silently humming along.