Rolls-Royce announced on June 28 that it is entering the hydrogen electrolysers market and acquiring a 54% majority stake in electrolysis stack specialist Hoeller Electrolyzer, whose technology will form the basis of a new range of Rolls Royce mtu electrolyzer products from its Power Systems division. Hoeller Electrolyzer, based in Wismar, Germany, is an early-stage technology company that is developing highly efficient polymer electrolyte membrane (PEM) stacks, under the brand name Prometheus, for the cost-effective production of hydrogen.

Dr. Otto Preiss, COO and Chief Technology Officer, Rolls-Royce Power Systems, said: “By developing our own mtu electrolyzers and by taking a majority stake in Hoeller Electrolyzers, we are methodically growing our hydrogen portfolio and securing access to this fascinating technology, which is not a pipe dream but has great market potential. 

“This will enable us to supply complete hydrogen solutions and make a significant contribution to protecting the climate. Our complete hydrogen solutions will enable customers to store renewably produced energy in the form of hydrogen for use as and when required, or for further processing or onward sale.”

Stefan Höller, Hoeller Electrolyzer founder, has more than a quarter of a century’s experience of developing electrolysis technology and has already registered 14 patents connected with Prometheus. The company promises high efficiency electrolysers made possible by special surface technologies for the bipolar plates which significantly reduce the use of expensive precious metals platinum and iridium as catalysts, as well as increased output pressure.

With decades of experience, Rolls-Royce aims to develop a complete electrolyser system and has a global sales and service network, which opens up the potential for significant worldwide sales.

Matthias Kramer, CFO and Joint Managing Director, Hoeller Electrolyzer, said: “In Rolls-Royce, not only have we found an important customer for our stacks, we’ve also secured an ideal partner and supporter who shares our vision of putting stacks into full production.”

Development work on the first mtu electrolyser using a stack from Hoeller Electrolyzer is already underway. In 2023, it will go into operation at the Validation Center in Friedrichshafen to demonstrate how an electrolyser fits into the overall architecture of a microgrid. An initial customer project is already planned for 2024.

Armin Fürderer, head of the Net Zero Solutions business unit of Power Systems, said: “We’re going to launch electrolysers with several megawatts of power right from the start. A total output of over 100 megawatts is conceivable by combining several electrolyzers.”

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 are not being disclosed. Stefan Höller and Matthias Kramer will continue to lead Hoeller Electrolyzer as a standalone company, with the goal of building a leading international stack manufacturer.