If hydrogen, which is a highly-efficient energy carrier, could be produced, stored and used at sea in tandem with wind turbines, it would greatly reduce the need for expensive subaquatic grid connections to the mainland. Researchers at the Fraunhofer Institute for Machine Tools and Forming Technology (IWU) are therefore looking into novel electrolysers and storage systems for offshore use in “H2Wind”.

Mark Richter, head of the 'Future Factory' at IWU, explains the advantages of the new approach in a press release: “Wind is almost always available. This enables steady electricity production. In addition, there are no restrictions such as distance regulations on land,” he says. However, he admits there are significant technical challenges: “Electrolysis on the open sea takes place under robust conditions. The overall system as well as the individual components must be designed for this so that they function reliably for many years and a maximum yield of wind energy is achieved with them."

For research purposes, the team are developing a fuel cell stack – the power source of an electrolyser – which uses multiple bipolar plates that are specially adapted for offshore use. Suitable materials and production processes, such as coating strategies, are being investigated by the team, building on the IWU’s expertise in plate production processes.

The proposed offshore storage system is based on tubular storage tanks, similar to those used for natural gas. More investigation needs to be done, however, into how H2 will affect the materials and joints of the tubes and to this end a simulation tank is being built at IWU in Gorlitz. In addition, digital twin applications will be employed to assess the new offshore technologies.

H2Wind has received EUR 3.5 million funding within the H2Mare umbrella project, which is funded by The Federal Ministry of Education and Research (BMBF) with more than EUR 100 million and will run until 31 March 2025.