Or maybe it's expensive because it doesn't scale. The per-unit cost of nuclear power plants is extremely high, making it hard to get economies of scale in building more of them. And if we /do/ hit economies of scale, uranium availability is likely to become a problem...

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vablings 2 days ago | parent | next [-]

> The per-unit cost of nuclear power plants is extremely high, making it hard to get economies of scale in building more of them.

I disagree. building big infrastructure projects always scales well. As stated by the project managers at Hinkley Point C (the most expensive nuclear reactor ever) they estimate that build times and cost will be significantly reduced for the second reactor due to the knowledge and expertise baked into the workforce. Frances nuclear revolution during the 1972 oil crisis also shows the same thing with construction cost getting lower the more reactors built.

There are other reactor designs that do not use uranium that have been tested and hypothesized.

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jandrewrogers 2 days ago | parent | prev [-]

> per-unit cost of nuclear power plants is extremely high

Unless you are the US Navy. It probably helps that they churn out dozens of the same few cookie-cutter designs without needing permission from NIMBYs.

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epistasis 2 days ago | parent | next [-]

Those reactors were also very expensive, though, weren't they? I've heard lots of people look to them as a reason that SMRs might work, but not because the naval reactors were cheap. Plus they use uranium enriched to levels that we typically don't allow in civilian reactors...

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jandrewrogers 2 days ago | parent [-]

Even at military contracting prices, estimates put them at $100-200M each IIRC. That's not terrible.

The highly enriched fuel is used because it simplifies the design and maintenance. It eliminates all the machinery you'd need to support things like operational refueling of the reactor. Old designs still needed to be rebuilt every 25 years but the new ones are sealed systems that are never supposed to be cracked open over their design life.

I think the main reason we don't use HEU in civilian reactors is non-proliferation concerns, valid or not. Ideally you'd want maximally simple, sealed reactors for the same reason the US Navy does.

	▲	epistasis 2 days ago \| parent [-]
		I'm not finding much support costs being that low... best collection of info I have seen is here: https://www.construction-physics.com/p/why-are-nuclear-power... At 1.5-1.7x the cost of diesel ship, and the "well-managed" Virginia class costing $3.6B, we are at over $1B for 60MW of power, 200MW thermal, which is far worse than larger civilian reactors per watt. The reason we use nuclear submarines and aircraft carriers are their far superior operational characteristics when compared to hydrocarbon fuels. That benefit is massive and well worth it. For terrestrial grid electricity those benefits don't really exist.

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vablings 2 days ago | parent | prev [-]

Honestly not a terrible idea. Just have your reactor on a huge barge and if it goes meltdown just drag it out into international waters and let the fish deal with it /s

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larkost 2 days ago | parent [-]

An actual meltdown at sea would have the now-molten uranium come in contact with seawater, which would instantly flash to high-pressure steam, throwing the uranium into a cancer-causing cloud that the world has never yet seen.

This is absolutely a terrible idea about how to deal with a meltdown.

	▲	cbm-vic-20 2 days ago \| parent [-]
		Doing the math, it looks like the amount of uranium in pre-disaster Chernobyl is 200 metric tons. Apparently, that can bring 333ML (133 Olympic sized swimming pools) of room temperature water to a boil.