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Odd thoughts: Fuel cell as a battery, skip the hydrogen infrastructure

svetz

Works in theory! Practice? That's something else
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One of the arguments against fuel-cell EVs is quite reasonably the lack of hydrogen refilling stations in the U.S.

A reversible fuel cell can convert hydrogen into electricity, or electricity and water into hydrogen. Think of a gallon of gasoline as a battery with 33.7 kWh battery that is "full" at charge. A gallon of water represents about 25 kWh of "empty" battery before efficiencies.

So, why have hydrogen infrastructure (e.g., pipeline) for the home generators or EVs? Just treat them as empty batteries on delivery and pour in a few gallons of deionized water. Or for EVs, let them recharge from your solar during the day by making hydrogen.

We're not doing this today for two reasons: the system cost and the system efficiency. A hydrogen fuel cell is ~60% efficient, and electrolysis is up to around 80%. It just can't compare to LFP's roundtrip efficiency of 80%.

But, if the price came down... it might make sense for hydrogen fuel cell EVs to "recharge" at home as it decreases vehicle weight. Similarly, it could replace the battery for your home system. So, I went looking for them and they exist, but they're not economical. Wonder what it'll look like in a decade... probably the same, solid-state LFP will probably be blowing everything else away.

But, what do you think?
 

With the amount of solar and wind that we need to have in order to keep everything running 24*7, we are going to have times of large excesses. We could do useful things with it, like desalinate sea water to replenish reservoirs, or make hydrogen, both take massive amounts of energy which makes it uneconomical. However, at times when you do have excess power, it would be nearly free and make the process economical.
 
... We could do useful things with it, like desalinate sea water to replenish reservoirs, or make hydrogen, both take massive amounts of energy which makes it uneconomical. However, at times when you do have excess power, it would be nearly free and make the process economical.
Wow! Adding load for the public good rather than throw it away! Genius idea!

That sure beats the utilities dialing back DER output (e.g., homeowners with solar) via frequency control because there's "too much power".
Wish you were there when they were drafting CA Rule 21, HECO 14H, Puerto Rico PREPA/PECO. etc. If you're running for office send me an email, you just won my vote. ;)
 
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Wow! Adding load for the public good rather than throw it away! Genius idea!

That sure beats the utilities dialing back DER output (e.g., homeowners with solar) via frequency control because there's "too much power".
Wish you were there when they were drafting CA Rule 21, HECO 14H, Puerto Rico PREPA/PECO. etc. If you're running for office send me an email, you just won my vote. ;)
Not that I am running, but thanks for the vote, most of those things could be done commercially as well.

Without storage, at some point curtailment will still be happening, the grid can only cope with so much. Expect engineers and bean counters to clash again, add in big business trying to preserve their subsidies and monopolies, together with politicians spreading misinformation and it is going to be messy for quite some time. Just look at global warming denial, or anti-vaxxers if you want examples.

If only we could get engineers to fix the problem....
 
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