The problem with “from water” is that it takes as much energy to separate the hydrogen and oxygen in water as you get back by oxidizing the hydrogen to produce water. You can’t use water as a useful way to store hydrogen for energy because of that.
Good thing people have been able to use untreated ocean water as the feedstock. It looks like it needs to be scaled up, but the economic advantage should help incentivize that (seawater is free; treated water is expensive!).
The problem with “from water” is that it takes as much energy to separate the hydrogen and oxygen in water as you get back by oxidizing the hydrogen to produce water. You can’t use water as a useful way to store hydrogen for energy because of that.
Also, that’s our drinking water you’re turning into fuel.
Good thing people have been able to use untreated ocean water as the feedstock. It looks like it needs to be scaled up, but the economic advantage should help incentivize that (seawater is free; treated water is expensive!).