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by otp124 3256 days ago
Would it be possible to make them modular? As in, build X number of the best submarine-size reactors and drop them in side-by-side in essentially secure concrete warehouses cooled by water pumped from a nearby lake? Kind of like racking servers is what I'm picturing.
2 comments
philipkglass 3256 days ago
That's the "small modular reactor" concept, under development by a few companies. I think that the concept has considerable merits. I hope that it will be tested in practice. I'm pretty bullish on renewables but nuclear power is very low emissions over its life cycle, safe enough (IMO), and nuclear construction capability should be (again IMO) maintained as a complement/alternative to renewable generation for the post-fossil era. For continued viability new nuclear construction needs lower, more predictable costs or steady long-term support from governments; I think that cost improvements would be the better of the two.
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otp124 3255 days ago
Sounds like a viable model, thanks!
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acidburnNSA 3256 days ago
One advantage submarine reactors have is that they can use fully enriched uranium (bomb-quality, >90% U-235). You can still make pretty small reactors with non-weapons uranium (defined as <20% enriched) but they are not as performant or long-lasting as the pure U-235 submarines.
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otp124 3255 days ago
Interesting. So can the core of uranium weapons be re-used for nuclear reactors? (Assuming there is a big arms reduction event)
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cperciva 3255 days ago
Yes. Plutonium from disassembled nuclear weapons is also used this way, under the name "mixed oxide fuel". Some reactor designs are better at burning "MOX" than others; CANDU reactors are particularly good at this, and in the early post-cold-war years there was a very active US-Canada-Russia programme to use Canadian reactors to burn surplus Russian fuel, funded by the USA (which was very concerned about the potential for fuel from decommissioned Russian weapons to get onto the black market).
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acidburnNSA 3255 days ago
Absolutely. In fact, from 1993 to 2013, fully 10% of the electricity in the USA came from dismantled ex-Soviet nuclear bombs through just such a arms reduction effort [1]. The material was downblended with U-238 to take it from weapons-grade to reactor-grade. The bombs that were once pointed at American cities ended up powering them. It was glorious.

[1] https://en.wikipedia.org/wiki/Megatons_to_Megawatts_Program

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