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by pfdietz 1910 days ago
Not at all. The technology for hydrogen energy storage is (with the possible exception of cheap electrolysers) is off the shelf. It's not widely used not because it's not available, but because natural gas is cheaper to store and burn when there are no CO2 taxes. But the CO2 taxes will be raised enough to push natural gas out, if we're going to control global warming.
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mlyle 1910 days ago
When the largest electrolyzer we have in the world is 10MW... and hydrogen storage hasn't been demonstrated at anywhere near the scale you're talking about... it's a tad of a stretch to talk about it being "off the shelf." Particularly when you point to nuclear fuel reprocessing and breeding as nonexistent in the same thread.
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pfdietz 1910 days ago
We can run electrolysers in parallel to scale to any desired output level. There might be economies of scale to make them even larger, or there could be economies of manufacturing scale of making smaller ones at higher volume. PV and wind are examples of technologies that work well with large numbers of not so large units, replicated as needed. This is a nice place for a technology to be.
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mlyle 1910 days ago
A few prototype / demonstration units at 10MW scale and lower is not proven, off the shelf technology. Fullstop.
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philipkglass 1909 days ago
Electrolytic hydrogen plants of up to 250 MW were constructed in the 20th century by the use of smaller electrolysis units in parallel. All of them were for producing ammonia from hydrogen. See table 3-2 on page 99 of this NASA report from 1975:

"Survey of Hydrogen Production and Utilization Methods"

https://ntrs.nasa.gov/api/citations/19760008503/downloads/19...

250 MW, Rjakon, Norway, built 1965

170 MW, Kima, Egypt, built 1960

125 MW, Nangal, India, built 1958

90 MW, Trail, Canada, built 1939

25 MW, Curco, Peru, built 1958

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mlyle 1909 days ago
??? Those are input powers of terrifically inefficient and expensive electrolyzers. That 250MW plant put out 17MW of hydrogen -- (120 (megajoules / kilogram)) * ((0.000236 kilograms) / (cubic foot)) * (2 200 000 ((cubic feet) / hour)) = 17,306,667 Watts.
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philipkglass 1909 days ago
I think that you slipped a decimal point. The mass of a cubic foot of hydrogen is about 0.00236 kg, not 0.000236 [1]. That means that the output power is an order of magnitude greater than you calculated -- 173 megawatts.

[1] https://microsites.airproducts.com/gasfacts/hydrogen.html

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