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by thirdlamp 1699 days ago
Hydrogen will not be a threat to any electric personal vehicle simply because it’s 3x less efficient (electrolyze water to split it) and thus 3x more expensive to run.
1 comments

Really just a meme at this point. The risk here is that hydrogen cars end up being cheaper to run than electric cars. A real possibility due to the production of hydrogen from curtailed renewables, higher battery costs, hydrogen being much more efficient than believed, as well as cheaper distribution costs since hydrogen can be piped in natural gas pipelines.
> hydrogen being much more efficient than believed

God/Allah/Nature obviously don't understand disruption, growth mindset and can-do-spirit. facepalm

There are hard physical limitations that no amount of human ingenuity can do anything about. 237kJ/mole is the theoretical minimum of energy required for water electrolysis. energy->electrolysis->energy round-trip efficiency won't exceed 45%, even if everything, from the energy source to the car wheel spinning, is perfectly frictionless and operating at peak theoretical efficiency. No, you cannot use existing gas pipelines for transporting hydrogen.

For passenger cars, EVs today are already better than what physics allow hydrogen cars to ever be.

Except you can extract 237 kJ/mole from hydrogen. A fuel cell is a battery and can approach the efficiency of a lithium-ion battery.

> No, you cannot use existing gas pipelines for transporting hydrogen.

You absolutely can. In fact gas companies are already planning this exact thing.

> For passenger cars, EVs today are already better than what physics allow hydrogen cars to ever be.

Your "physics" is entirely pseudoscience.

I thought too you can but it's only theoretically, not absolutely. See for example: https://youtu.be/vrKvj2MHLVw
I prefer opinion of independent expert over that of technology vendor soliciting EU's investment. But even they say "won't be before 2030" anyway.
Does hydrogen get added back into the fuel cell as the car breaks?