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You're probably not going to run a semiconductor fabrication plant and/or AI training intermittently. These are very expensive machines and hence you want to maximise utilisation even if you have to pay more for electricity. Utilisation is a big deal for capex heavy industries.

I doubt green hydrogen will be as big of an industry as the pundits are making it out to be. Solar electricity to hydrogen to heat is an extremely inefficient process. Transport and heat will mostly be electrified. You can efficiently convert electricity to heat and store that heat in heat batteries for months at very low losses.

Hydrogen is mostly be used a feedstock for making chemical like plastics. Hydrogen will not be a big player in the steel industry. When electricity is cheaper than heat, more industrial processes will shift from thermochemical systems to electrochemical systems as demonstrated by companies like Boston Metals.

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Right, to take advantage of cheap solar you have to reorient your process to have low capex. For some industries that's doable, for others they might need some battery storage, and for some solar+batteries might never make sense.

There are lots of silly proposals for green hydrogen that I don't endorse. It's nasty stuff that shouldn't be stored for a long period of time. But for chemical plants that can run intermittently and use the hydrogen immediately I'm pretty optimistic!

(And definitely don't use hydrogen for heat, just run heating coils or a direct current arc furnace like steelmaking has been doing for decades)

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Arc furnaces only lets make refined. The most energy and emissions intensive part is ironmaking.

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Great article. One of the few business leaders who seems to recognize the interplay between ideas and scale is Elon Musk.

The Starship rocket, which I have written about a few times, is intended to be the world’s first fully and rapidly reusable rocket. But Musk and his engineers recognize that being reusable is not enough, launch frequency, or scale, is (actually) more important.

Just as a 737 would not be economical to fly once a month, even if it wasn’t expended, a rocket cannot be grounded for weeks at a time. To make space access affordable, rockets have to become like airplanes…always launching and landing. He then extends this interplay to rocket design and production. The more frequently a rocket flies, the more opportunities engineers have to identify failure modes and improve the design to scale up reliability.

Doing this requires rapid production and iteration, so he has built a rocket factory that hopes to churn out Saturn V-sized rockets once every few days. What SpaceX, at Musk’s behest, is borderline insane. It’s rational madness that is built on an understanding of scale.

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