Engine manufacturer Rolls Royce is entering the hydrogen production market by acquiring a 54pc majority stake in German electrolyser stack specialist Hoeller Electrolyzer.

The latter’s technology will form the basis of a new range of electrolyser products from Rolls Royce’s power systems division.

Hoeller has developed proton-exchange-membrane (PEM) stacks under the brand name Prometheus.

The firm does not publish efficiency figures for its electrolysers but says they are significantly higher than conventional PEM models thanks to surface technologies for the bipolar plates that reduce the use of platinum and iridium as catalysts and increase output pressure. It has already registered 14 patents connected with Prometheus.

“Our stack is going to produce hydrogen at a price not previously thought possible,” says Stefan Hoeller, managing director of Hoeller Electrolyzer.

14 – Patents registered by Hoeller Electrolyzer

Rolls Royce will take a methodical approach to growing its hydrogen portfolio, developing a complete electrolyser system to market through its global service and sales network.

“This will enable us to supply complete hydrogen solutions and make a significant contribution to protecting the climate,” says CTO Otto Preiss.

Development work on the first electrolyser using a stack from Hoeller is already underway and will go into operation at the firm’s testing centre in Friedrichshafen in 2023. An initial customer project is already planned for 2024.

The first electrolysers will have “several megawatts” of power, and a total output of more than 100MW is conceivable by combining several units, Rolls Royce says.

The equity in Hoeller Electrolyzer now held by Rolls Royce comes from departing minority shareholders and from an increase in share capital. Financial details of the transaction were not disclosed.

Electrolyser investment

Rolls Royce adds to a recent spate of firms investing in electrolyser production divisions.

Technology firm Bosch is to launch a new business unit to develop components for electrolysers, investing €500mn ($527mn) in the venture by 2030.

In addition, German technology firm Siemens Energy and French industrial gases group Air Liquide have formed a joint venture targeting 3GW/yr of production by 2025.

Meanwhile, UK-based fuel-cell technology firm Ceres Power is building a 1MW solid-oxide electrolyser that will become operational in 2022 as part of its efforts to expand its electrolyser division.

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Author: Tom Young