Hoeller Electrolyzer is an early-stage technology company developing polymer electrolyte membrane (PEM) stacks, under the brand name Prometheus, for the cost-effective production of hydrogen. The demand for ‘green’ hydrogen is expected to rise, making high-performance electrolysers a key component of any hydrogen system.
Hoeller Electrolyzer’s technology will form the basis of a new range of mtu electrolyzer products from Rolls-Royce’s Power Systems division.
In a statement, Dr Otto Preiss, COO and Chief Technology Officer, Rolls-Royce Power Systems, said: “By developing our own mtu electrolysers and by taking a majority [54 per cent] 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.”
In hydrogen electrolysis, water is subjected to DC electrical current, producing hydrogen at the negative pole and oxygen at the positive pole. In this way, it is possible to produce carbon-neutral hydrogen by using electricity from renewable sources. The electrochemical reaction takes place in a cell between plate-shaped electrodes separated by membranes. Hundreds of cells located one above the other and pressed together form a 'stack', which is central to an electrolyzer.
With Prometheus, Hoeller Electrolyzer has positioned itself as one of the few highly specialized experts in high-efficiency PEM electrolysis stacks and its founder and managing director, Stefan Höller, has registered 14 patents connected with the technology. Particularly high efficiency is promised by special surface technologies for the bipolar plates which reduce the use of precious metals platinum and iridium as catalysts, as well as increased output pressure.
“Our stack is going to produce hydrogen at a price not previously thought possible,” said Höller.
Development work on the first mtu electrolyzer using a stack from Hoeller Electrolyzer is already underway. In 2023, it will go into operation at the Validation Centre in Friedrichshafen to demonstrate how an electrolyzer fits into the overall architecture of a microgrid. An initial customer project is planned for 2024.
Armin Fürderer, who heads up 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 100MW is conceivable by combining several electrolysers.”