To paraphrase Mean Girls, “stop trying to make hydrogen happen.”
For some years now, detractors of battery electric vehicles have held up hydrogen as a clean fuel panacea. That sometimes refers to hydrogen combustion engines, but more often, it’s hydrogen fuel cell electric vehicles, or FCEVs. Both promise motoring with only water emitted from the vehicles’ exhausts. It’s just that hydrogen actually kinda sucks as a fuel, and automaker Stellantis announced today that it is ending the development of its light-, medium- and heavy-duty FCEVs, which were meant to go into production later this year.
Hydrogen’s main selling point is that it’s faster to fill a tank with the stuff than it is to recharge a lithium-ion battery. So it’s a seductive alternative that suggests a driver can keep all the convenience of their gasoline engine with none of the climate change-causing side effects.
But in reality, that’s pretty far from true.
There’s three factors at play: depletion of the easiest reservoirs, sociological changes and increasing feasibility of competing technologies. The answer is going to depend on which things you’re assuming away.
Like, in this parallel modern world, is everyone using EVs, or horse and buggy? Early cars sucked - you basically had to be a mechanic just to own one, on top of the low speed, range and features - but they beat the shit out of no cars. It’s also worth noting petroleum products were burned in lamps first, so there was already a limited infrastructure for cars to use. If all the easy oil still isn’t there I doubt we’d bother, but with those gushing deposits of sweet crude just below Texas that used to exist the process would be much simpler.
The sociological one might be the easiest to answer. There’s plenty of heavy industry that’s nasty to be around, oil isn’t unique or even the worst offender, so that’s fine. If it’s the horse and buggy world people aren’t going to tolerate tons of steel whizzing them by with no enclosure, though. Most of that kind of thing was outlawed in the mid 20th century, but cars were just so ubiquitous. So, by that count, gas powered trains would be the application.
There’s a chance the greenhouse effect would be predicted and managed actively from the start, because science has come a long way. I’d guess urban air pollution regulation would end up in about the same place.