Lightcell: An engine that uses light to make electricity

Correct me if I'm wrong, but I don't see this being viable even if you reach your target efficiency.

The problem with hydrogen is the storage cost. Improving wire to to wire efficiency can help only so much. Have you calculated the electricity cost with those efficiency rates when you include the cost of storage? "Overall cost of renewable hydrogen in 2030 varies from €2.80–15.65/kgH2." improves with scale. https://www.sciencedirect.com/science/article/pii/S036031992...

Quick and dirty math, may contain errors:

Lightcell target is 0.5 kWh/L. Hydrogen weighs 0.09kg/L.

-> storage cost alone: ~ €0.5/kWh in large scale, €2.5/kWh in small scale.

Average electricity cost in the EU has been €0.289 per kWh.

Correct me if I'm wrong but I think this is apples and oranges: storage can be reused, while electricity is consumed.

That's the levelized cost over the lifetime. Hydrogen storage is expensive to both build and maintain.

The issues include hydrogen embrittlement, constant leakage and safety issues. Containers don't last. H2 is the smallest molecule. It gets into the containers and wears them out and leaks away. Casing and seal damage is constant. Pressure vessel storage loses little below 1% leakage per day.Liquid hydrogen storage is about 1-3% leakage per day. Salt cavern storage much less but they have problem of H2S generation by Micro-organisms.

> That's the levelized cost over the lifetime.

I don't see how you can compute that cost if you don't know anything about the amount of energy that goes into and out of the container, and how often that happens.