Look at this hydrogen fuel cell. It's made fully at home, even membrane. 1x1 inch (2x2 cm) of Nafion membrane costs 20$, I made it by myself for free. I got 0.3 volts.

Why hydrogen fuel engines are not popular? It's good for ecology, good for gas prices.

Look at this hydrogen fuel cell. It generates 0.3 volts, fully homemade, membrane too.
Rate.