Rather than focusing on hydrogen, I think a more realistic option would be to stop at an intermediary step proposed in your OP.


We have plenty of methods of storing, utilizing, and transporting electrical energy generated from wind farms or solar panels. By focusing on converting that electrical energy back into a combustible source, we've already lost a fair bit of energy. On top of that, hydrogen is obscenely dangerous. Its molecular structure is so small that it can't reliably be contained in a gaseous phase. I'm not sure if it could be odorized the same way natural gas is, but at this point as far as I know, there is no way to detect gas leaks besides just assuming they are there. Another major issue is that its combustion is a temperature far higher than what modern combustion engines can handle. I use an oxyhydrogen torch that I've gotten pretty close to melting tungsten with at ~6200 degrees Fahrenheit. I know there are catalysts that can lower the temperatures, but that involves another process, another cost, another new piece of machinery to engineer, and another failure point.

My point isn't that it shouldn't be done, I'm sure there are proper ways to handle hydrogen safely, but if the first step is creating it by splitting water, even assuming that we are using Nickel Oxide catalysts rather than platinum to make it economically feasible, it requires that the energy is available in the first place. If we are generating the power needed to create the hydrogen gas in a green fashion, and the only perk to using hydrogen is that we can transport the energy, I'd propose focusing on improving battery technology, or ideally making the switch over to capacitors once we can figure out how to increase their capacities.