Reactors for Hydrogen Production

To date, electrolysis, in which hydrogen is produced by splitting water using electricity, has been the dominant process. However, as the generation capacities of wind and solar power plants required for the production of green hydrogen are limited, the National Academy of Sciences recommends further developing alternative processes. Artificial photosynthesis, or photoelectric water splitting, in which hydrogen is produced from sunlight and water, is mentioned in this context. At present, this process is not yet technically mature and cannot yet be operated economically.

The Fraunhofer CSP, together with Gebr. Schmidt GmbH and six other partners from industry and science, will further develop SunHydrogen Inc.'s patented photoelectrochemical technology from a laboratory setup to a demonstration plant. In this process, the photoelectrodes are formed from nanometer-sized tandem solar cells based on semiconductors embedded in aluminum oxide.

To this end, the current manual production process, which only allows low quantities to be produced in varying quality, will be further developed into an automated production technology. New solutions must also be found for the measurement technology, which is currently still being adopted from other technologies that do not take the requirements of photoelectrochemistry into account, in order to ensure the economic implementation of research results as well as industrial development and the control and further development of the production process and products.

The Fraunhofer CSP is the project coordinator and is responsible for developing a scalable LED solar simulator test rig for solar reactors and an open-air test rig for long-term investigation of the demonstration plants under application conditions.

The photoelectronic reactors developed are used where small amounts of hydrogen are required and do not require extensive investment. They are intended, for example, for storing solar energy in residential buildings or for small businesses whose forklifts or other utility vehicles are powered by hydrogen.