Green hydrogen is considered to be one of the key technologies for the climate-neutral transformation of industry and the energy system. However, its production has so far been expensive, technically complex and heavily tied to existing infrastructure. This is precisely where photreon comes in: The KIT spin-off is developing a photoreactor panel that produces hydrogen directly from sunlight and water - without electrolysis and without an electrical energy supply.

"We are skipping the detour via electricity-based electrolysis and producing chemical energy from the sun and water," says co-founder Paul Kant from the Institute of Micro Process Engineering (IMVT) at KIT. The aim is to use modular panels to make solar hydrogen production simpler and at the same time economically scalable.

Light as a direct driver of the reaction

Technically, the approach is based on photocatalysis. In contrast to photovoltaics, where light is first converted into electricity, solar energy is used directly to trigger chemical reactions. Special light-active materials absorb the energy of the radiation and put electrons into an excited state. These then enable the splitting of water (H₂O) into hydrogen (H₂) and oxygen (O₂).

"Photovoltaics and electrolyzers are replaced by the photoreactor panel in a single process step," says Maren Cordts from IMVT, who is also a co-founder, explaining the principle. "This significantly reduces system costs and complexity in the production of green hydrogen."

This is implemented using a photoreactor panel for which KIT has filed a patent application. Its geometry is designed in such a way that the sunlight is directed specifically into the interior, where it illuminates the active material evenly. "We designed the reactor geometry in such a way that light transport, chemical reaction and removal of the products interact optimally and were thus able to demonstrate hydrogen production in our one-square-meter prototype," says Kant.

The system is also designed for industrial production and can be manufactured using standard mass production processes and inexpensive materials. Thanks to its modular design, it can be used in small spaces as well as interconnected to form larger areas.

Use from the factory roof to the solar park

The technology is intended for applications in which hydrogen is currently too expensive or logistically difficult to obtain - for example in specialty chemicals, the food industry or metal processing. Large-scale solar projects in regions with high levels of solar radiation should also be possible.

"Our technology opens up new scope for local production, especially in places where there are neither electricity grids nor a connection to a hydrogen network," says Cordts. The spectrum ranges from the decentralized supply of individual production sites to industrial production for the international market.

Hannover Messe 2026, Hall 11, Stand B06