Love that the storage tech is only mentioned in 2 sentences and only described as using an oxide.

They are very cagey about the details of how this works, yet their website says individual components have been validated by SINTEFF, the Norwegian Foundation for Industrial and Technical Research. They have a long list of companies they’ve spun off from basic research breakthroughs. If they have validated this technology, then it at least works in the laboratory.

Based on a feasibility study undertaken by SINTEF, a leading European science research institute, a team of engineers and scientists at Photoncycle developed and validated individual components for our system in 2022. These were integrated and scaled into a functioning prototype of our core technology at the Photoncycle lab in 2023. A full-scale pilot will be developed in 2024 and a first product will be launched in the residential household market in 2025

They claim their volumetric energy density is 3.3kWh/L, which is very good for hydrogen. The 3.5kWh/kg gravimetric energy density is very bad for hydrogen, but good compared to batteries.