The operating principle of power-to-gas is based on a chemical process: water electrolysis. Water is split into hydrogen and oxygen using electricity. The hydrogen obtained in this way subsequently contains a large part of the energy input. Since no greenhouse gases are released during electrolysis and subsequent use, hydrogen is considered emission-free (“green hydrogen”) if the electricity used comes from renewable energy sources.
Two technologies are currently available for large-scale electrolysis of water: alkaline and proton exchange membrane electrolysis. Amprion and OGE are considering both technologies with their respective advantages and disadvantages for use in the project.