We should just be running on hydrogen cars also (this could keep sea level in check) although in the future if we use to much water it may fuck up out orbit.
There is enough thermal energy on our planet to sustain every city a billion times over, clean thermal energy that is being created by nature.
also, if we start burning up hydrogen from the oxygen it only takes 4% of oxygen to burn all the hydrogen, so you are left with oxygen in the atmosphere, perhaps we can use that on mars.
We won't be changing the Earth's orbit with anything we do.
Nobody has really demonstrated fuel cells to be cost effective or practical.
I think Lzar has
If they stopped getting killed they could to, it cost effective trust me, take a car battery and electrify the water inside of a tub, light that shit it is more explosive than fossil fuels and safer because you do not create more than you burn so no bombs can be created, even safer in a car crash.
https://www.youtube.com/watch?v=wjeM2IBhtlc
I don`t know if this is troll of not, but I know you can run a lawnmower on hydrogen I did it was I was 12.
Practical, low cost automotive fuel cell power does not exist.
Storage of compressed hydrogen is a problem.
Gasoline really has a lot of advantages.