I have been pondering for some time about hydrogen loss on planet earth. I've read a little about jean's escape and how helium and hydrogen can leave earth's atmosphere through said mechanism. my quandary has to do with hydrogen synthesis, be it electrolytic or otherwise. let's say hypothetically that we as a civilization never developed fossil fuels, but instead focused on hydrogen production/ sequestration in subterranean porous rocks for storage. if these processes were to have gone on at a global level for 200 years or more, what effect might that have had on the environment?

Where is the energy to produce the hydrogen coming from?

hypothetically, from various sources, wind mainly, but if it were to have been going on two hundred years ago, beasts of burden turning flywheels too. also, in the scenario, hydrogen and oxygen synthesis methods and hydrogen cumbustion engines would have been advanced at the turn of the eighteenth century