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Comment by rr808 | Hacker News Reader

Interestingly with steel being made with electricity instead of coal, the best places for steel mills are deserts on the equator with lots of solar, like North Africa, the Middle East.

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Shipping of raw resources is cheap. Much of the bauxite used in aluminum cans in N America is shipped to Kitimat BC [0] to be smelted. Aluminum is notoriously electrically expensive.

0 https://en.m.wikipedia.org/wiki/Kitimat

Iceland is a player too IIRC.

> Shipping of raw resources is cheap

Cheap in terms of money, maybe.

Less so in terms of emissions: https://www.statista.com/statistics/1291468/international-sh...

Not inherently, nothing is cheaper than hydropower.

How reliable is hydropower now though? I’m living in a place which normally sees huge snow falls each year, this melting snow runs hydro, guess what ? We have about 15% of our usual base and next week it's going to be +10c average.

Not necessarily true at this point for new projects. IRENA indicates wind projects commissioned globally in 2022 had a weighted average LCOE of $33 USD/MWh. Hydropower projects over the last decade or so (2010–2021) were around $39 to $48. (2022 average was $61, but obviously recent market conditions were far from normal)

AFAIK, LCOE are known to be misleading when comparing electricity sources with different power characteristics and applications.

https://www.wri.org/technical-perspectives/insider-not-all-e...

Wind, with it's availability of ~60% is not massively different from other energy plants with their availability of 80 - 92%.

Solar is worse, but since most modern high quality tables include LCOE's for "solar" and "solar+battery" with very different numbers, it shouldn't be misleading.

Wouldn't the need for labor, a supply of ore, and a means of delivering the product all argue for a port city? There aren't many railroads in those deserts. Or steelworkers.

There are plenty of ports in those areas.

The best place is next to nuclear power plant. Nuclear power is good because it has few restrictions on locations.

Using expensive electricity for an energy intensive process seems like a good way to lose money.

Nuclear puts out a lot of heat. Retooling iron/steel foundries to use that heat directly (instead of converting it into electricity and back into heat) seems like the way to go.

Color me skeptical. Waste heat from a nuke plant is very low quality compared to the extremely high heat needing to make molten steel. We aren't taking about warming potato greenhouses here.

...low quality heat? Nuclear reactors produce nothing but heat. And it's all just heat, how you transfer it is very independent of the production process

https://en.m.wikipedia.org/wiki/Energy_quality

This is very wrong. Different processes require different temperatures. Iron and steel making requires very high temperatures. Heat from nuclear reactors cannot be used for this directly, as nuclear reactors do not get that hot, because they would melt. They are kept much cooler, usually at under 500 C.

Current reactor designs cannot get that hot without melting. I bet we could design a molten salt reactor that could safely get there, especially if electricity production is not a design goal.

I seriously doubt that. What would you make the reactor of, so that it withstands temperatures that melt steel? How are you going to move that coolant around? There are hard physical limits here. In reality, nobody would bother, because you can just make electricity and use it to melt steel instead.

Nuclear lightbulb engine - but for process heat!

https://en.m.wikipedia.org/wiki/Nuclear_lightbulb

Like it was not crazy dangerous enough. ;-)

I wonder how you’d transfer the heat without exposing the steep to radiation. I assume that would be bad anyways. I wish I paid attention more in physics, would love to know how such a system could be built.

A trivial heat exchanger does that, and every nuclear power plant already has one.

Today we avoid radiating electric generation equipment by running two steam loops through a heat exchanger; one that interacts with the hot reactor and a second that spins the generators. Perhaps you could do similar with molten salt loops? Might be tough finding a material that would work as an exchanger at the required temperatures though.

Just using electricity is probably cheaper and easier; large power plants are crazy efficient already.

Thorium-based reactors famously are constrained by the lack of such material which would withstand the contact with hot molten salt, especially somewhat radioactive.

As anyone with a boat knows, salt water is insanely corrosive and gets into everything. Even large container ships have to be regularly serviced.

I can only what hot molten salt does to industrial processes.

Optimally, next to a source of water that can be split into hydrogen, ready to be used for the chemical process producing the pure iron. (Not the process in TFA.)

An array of SMRs (small modular reactors) located at the steel factory could be used – and would be sufficient – both for heating and producing the electricity without interruptions caused by fluctuating prices or blackouts.

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