Comment by aunty_helen
19 hours ago
It’s not even the grid, by the time you’ve done the electrolysis you’d be better off just charging a battery.
Also, compressing and cooling a gas takes another huge hit at the efficiency. Electrolysis comes out at atmospheric pressures.
Oh and the platinum electrodes you need…
I’m also just now visualising a hydrogen pipeline fire… terrible terrible idea.
It's the everything, yeah. There's a lot working against using hydrogen as the local energy source for automotive propulsion in the world that we presently have.
Some advantages are that a fuel cell that accepts hydrogen and air at one end and emits electricity and water at the other can be lighter-weight than a big battery, and it can [potentially] be refueled quickly for long trips.
Some disadvantages: We need a compressed hydrogen tank -- which isn't as scary to me as it may be for some people, but that's still a new kind of risk we need to carry with us wherever we drive. And we still need a big(ish) battery and the controls for it in order for regen braking to do its thing (which hybrids have shown to be very useful).
And, again, the grid: If it were cheaper/better/efficient to move energy from electrical generating stations to the point of use using buckets [or trucks or trains] of hydrogen, we'd already be doing that. But it isn't. So we just plug stuff in, instead, and use the grid we already have.
A quick Google suggests that a regular 120v US outlet might charge EVs at a rate somewhere in the range of 3 to 5 miles per hour. So a dozen or so hours sitting, plugged in at home every day, is enough to cover most folks' every-day driving. There's far faster methods, but that's something that lots of regular people with a normal commute and normal working hours can already accomplish very easily if they have private parking with an outlet nearby.
For most folks, with most driving, that's all they ever have to do. It shifts concerns about refueling speed from "Yeah, but hydrogen is fast! I waste hardly any time at all while it refills!" to "What refueling stops? I just unplug my car in the morning and go. I haven't needed to stop at gas station in years."
The main advantages of hydrogen are real, but they just aren't very useful compared to other things that we also have.
Also, what pipeline operator is going to want to move hydrogen when almost all other products are more valuable?