If the hydrogen is powered from solar/wind, then fuel cells process that into heat for homes, electricity for lights, and purified water for drinking.
For example if you have solar/wind energy, you can transfer it very efficiently over existing power grid to provide energy for heating or lights. Transmission losses in power lines are 8-15% so the efficiency is 85%+ (https://blog.schneider-electric.com/energy-management-energy...)
If you do the same via hydrogen, you have to convert solar energy into hydrogen. That conversion is only 16% efficient i.e. you loose 84% of solar energy (https://www.nrel.gov/news/press/2017/1117-nrel-establishes-w...).
Then you have to transport the hydrogen from where it's made to where it's used. That's additional expense and efficiency loss.
Then you have to convert hydrogen back into energy. Additional loss of efficiency.
It just doesn't make sense economically (https://phys.org/news/2006-12-hydrogen-economy-doesnt.html).
Hydrogen is not an electricity source. It doesn't compete with solar or wind.
It's electricity storage. It competes with batteries and it's not winning there either because of much greater efficiency losses and the fact that you would have to build (expensive) infrastructure (think network of gas stations, except for hydrogen).
* Flow batteries
* Hydrogen research (production, distribution, home & automotive fuel cells)
* Stronger permanent magnets
* Cost effective superconductors (rather than room temperature semi-conductors)