Oh that’s a good idea too. If the hydrogen and electricity is green, it’d have less of an environmental than batteries.
It isn’t. The amount of green hydrogen is a fraction of a fraction a percent of all hydrogen. The rest is all made from natural gas and the CO2 is released into the air. It’s a green washed fossil fuel.
“Green hydrogen”, is also incredibly inefficient in its own right. Approximately a 70 percent loss of energy compared to 15-20 percent for battery storage. It would literally be just as efficient to burn natural gas in a power station (with a 50+ percent efficiency, modern power turbines are very efficient) and use that power to charge a battery. The entire “hydrogen economy” has been a pipe dream by either complete morons or fraudsters (probably both). (Hydrogen aeroplanes might actually work, but that is by combustion and jet engines are already very efficient).
But if they’re making the stations, they can use or manufacture green hydrogen. It just a matter of the political will.
But if they’re making the stations
But they’re not. See: this article. They’re not profitable, and if they ever were, it was propped up by greenwashing a byproduct of natural gas production.
Today, green hydrogen is essentially an expensive, low-efficiency battery.
That could change with future work on making more efficient hydrolysis, but today, the numbers really don’t work out on green hydrogen vs alternatives like lithium ion or overhead wires for busses.
But a hydrogen battery has much much better specific energy than lithium ion. So you can have a much longer range.
Hydrogen is very light, so the energy per kilogram is quite high.
However, hydrogen is also naturally not very dense. Hydrogen at 1 atmosphere has a tiny fraction of the energy of a similar volume of batteries. Pressurized hydrogen is similarly dense to a battery, and liquid hydrogen is about twice as dense.
So to make hydrogen dense, you need a very thick, heavy tank to hold the pressurized hydrogen. That significantly cuts into your weight advantages.
Add to that, fuel cells are very inefficient at converting hydrogen to usable electricity.
