In the future, hydrogen (H₂) will play a significant role in the sustainable supply of energy and raw materials to various sectors. Therefore, the electrolysis of water required for industrial-scale H₂ production represents a key component in the generation of renewable electricity. Within the scope of fundamental research work on cell components for polymer electrolyte membrane (PEM) electrolyzers and application-oriented living labs, an MW electrolysis system was used to further improve industrial-scale electrolysis technology in terms of its basic structure and systems-related integration. The planning of this work, as well as the analytical and technical approaches taken, along with the essential results of research and development are presented herein. The focus of this study is the test facility for a megawatt PEM electrolysis stack with the presentation of the design, processing, and assembly of the main components of the facility and stack.

Herein we discuss polymer electrolyte membrane (PEM) electrolysis stacks and systems we developed that are optimized for direct coupling to a photovoltaic (PV) panel. One advantage of PEM systems is their use of non-corrosive and non-toxic media. Thus, safe outdoor operation can be guaranteed, even in the case of a leakage. The system design was adapted to reduce the number of connection tubes, allowing for a series connection of multiple stacks at low cost and high reliability. One coupled PEM/PV system was tested under various temperature and irradiance conditions. All system components were also thoroughly characterized. The characterization was used to calibrate simple models of the individual components. Finally, the models were used to predict the system’s solar-to-hydrogen efficiency under different operating conditions and to find an optimal configuration for real-world outdoor operation.