Application of photo-electrochemical hydrogen production for autonomous solar based electricity supply

Utilization of photovoltaic (PV) generated electricity in power systems detached from the public grid usually requires both short term storage for the compensation of day/night cycles as well as long term storage for smoothing the seasonal energy harvest distinctions. Prototype systems relying on an accumulator for short term and a hydrogen path - consisting of electrolyzer, hydrogen tank and hydrogen gas engine based generator (or alternatively a fuel cell) - as long term storage have proven well in various prototype plants. A disadvantage is the electricity based generation of hydrogen for the long term storage path; rather, direct solar hydrogen production using innovative photo-electrochemical (PEC) cells - which are newly available - eases and simplifies both plant design and operation. In the following these photo-electrochemical cells are briefly characterized and their potential exemplary application for the autonomous electricity supply of an industrial plant in several configuration variants is investigated.