Are hydrogen fuel cells efficient? I dont know anything about them
The primary problem with Hydrogen is storage and transport. Steel tanks look like cheesecloth to Hydrogen.
Think about it, from what do you fabricate a container for the smallest of all elements?
Some light reading on the state of the tech
https://hackaday.com/2019/09/04/are-hydrogen-cars-still-happening/The Hindenburg was able to hold some hydrogen. I am confident the tech has evolved since.
Sorry Hairy, but that comes off as hand wavey.
Hydrogen has decent energy density by
weight, but very poor energy density by
volume. The Zeppelins were very low pressure propositions. In order to carry a useful amount for fuel use in an acceptable volume very high pressures are needed, something on the order of 700bar.
Trust me, this is a real problem. There are solutions, but as always these too come at a cost.
I dont claim any knowledge of hydrogen as a fuel.
Can you just liquefy it? Thats how LNG is shipped across the ocean.