Operational Results of an 150/30 kW RSOC System in an Industrial Environment

The integration of renewable energy into industrial processes has a high potential for moving to a competitive low‐carbon economy in 2050, as targeted by the European Commission. The vision of the GrInHy project is to provide ‘green’ hydrogen via electrolysis using renewable electricity and to provide grid management services as a reversible generator in the iron‐and‐steel works of Salzgitter Flachstahl GmbH (Germany). Therefore, an reverse solid oxide cell (RSOC) system was built with a nominal electrolyzer power consumption of 150 kWAC and a power output of 30 kWAC in fuel cell operation with hydrogen, respectively, 25 kWAC with natural gas. A key outcome of the project is to prove high system efficiencies up to 84%LHV in electrolysis mode and more than 50%LHV in fuel cell mode with natural gas are achievable in a real life system. It also showed long‐term operability at degradation rates < 1% kh−1. The findings and results of the first 5,000 h of operation are presented in this paper. The GrInHy prototype demonstrates the technical feasibility of the integration of an RSOC system in an industrial environment as flexible load or power source. It proves that steam electrolyzers have reached a technical readiness that allows their scale‐up to a level at which real life customer demands can be covered.