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by thow-58d4e8b 1699 days ago
> 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.

1 comments

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.
It will likely be a transition from blended hydrogen before reaching 100% hydrogen later. Just because it won't happen all at once doesn't mean it hasn't already started.
I am not against hydrogen, but seems to me as if nobody in the space is noticing the disruption what electrical batteries already are. If battery trends continue by 2030 the value of refitting infrastructure to hydrogen easily becomes questionable [note], when there's a way to both transport and store energy more efficiently and at the same price if not cheaper. There are no signs of battery improvements to stop anytime soon or price to stop dropping.

[note] for pure hydrogen eventually everything except the pipelines will have to be replaced

Does hydrogen get added back into the fuel cell as the car breaks?