5 ms·

Maybe someday those power plants will be available in smaller sizes, e.g. for fusion with the discovery of better confinement techniques, or high magnetic field

by dest 9y ago

Maybe someday those power plants will be available in smaller sizes, e.g. for fusion with the discovery of better confinement techniques, or high magnetic field materials

milcron 9y ago
Nuclear plants were originally designed small, as for submarines. For some reason the design trend has been towards larger plants. Perhaps for economies of scale? An interesting watch is Adam Curtis' documentary "A is for Atom", which covers the history of nuclear power. It's usually pretty easy to find Adam's content on youtube: https://www.youtube.com/watch?v=S3i9WHHl3qA https://www.youtube.com/watch?v=S3i9WHHl3qA https://www.youtube.com/watch?v=-FDrA7yUdFc https://www.youtube.com/watch?v=-FDrA7yUdFc Summary on Wikipedia: https://en.wikipedia.org/wiki/Pandora%27s_Box_(TV_series)#Part_6._.27A_Is_for_Atom.27 https://en.wikipedia.org/wiki/Pandora%27s_Box_(TV_series)#Pa...
- philipkglass 9y ago
  The larger reactors were supposed to improve the economics of nuclear power once they reached series production. Making the minimum size larger seems to have impeded progression toward series production, zeroing out (and then some) the expected reduction in cost-per-megawatt from larger units. For example, the 1117 MWe AP1000 design that's driven Westinghouse to bankruptcy derives from the AP600 design of only 600 MWe. After-the-fact criticism is too easy, but it seems to me that Westinghouse and its US partners would have suffered less if they were trying to build 4x 600 MWe reactors, and the projects fell behind schedule/over budget, than in their actual situation where they're behind schedule/over budget on 4x 1117 MWe reactors.
  - otp124 9y 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.
    - philipkglass 9y 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.
      - otp124 9y ago
        Sounds like a viable model, thanks!
    - acidburnNSA 9y 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.
      - otp124 9y ago
        Interesting. So can the core of uranium weapons be re-used for nuclear reactors? (Assuming there is a big arms reduction event)
        cperciva 9y 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).

by dest 9y ago

Maybe someday those power plants will be available in smaller sizes, e.g. for fusion with the discovery of better confinement techniques, or high magnetic field materials

milcron 9y ago

Nuclear plants were originally designed small, as for submarines. For some reason the design trend has been towards larger plants. Perhaps for economies of scale? An interesting watch is Adam Curtis' documentary "A is for Atom", which covers the history of nuclear power. It's usually pretty easy to find Adam's content on youtube: https://www.youtube.com/watch?v=S3i9WHHl3qA https://www.youtube.com/watch?v=S3i9WHHl3qA https://www.youtube.com/watch?v=-FDrA7yUdFc https://www.youtube.com/watch?v=-FDrA7yUdFc Summary on Wikipedia: https://en.wikipedia.org/wiki/Pandora%27s_Box_(TV_series)#Part_6._.27A_Is_for_Atom.27 https://en.wikipedia.org/wiki/Pandora%27s_Box_(TV_series)#Pa...

philipkglass 9y ago
The larger reactors were supposed to improve the economics of nuclear power once they reached series production. Making the minimum size larger seems to have impeded progression toward series production, zeroing out (and then some) the expected reduction in cost-per-megawatt from larger units. For example, the 1117 MWe AP1000 design that's driven Westinghouse to bankruptcy derives from the AP600 design of only 600 MWe. After-the-fact criticism is too easy, but it seems to me that Westinghouse and its US partners would have suffered less if they were trying to build 4x 600 MWe reactors, and the projects fell behind schedule/over budget, than in their actual situation where they're behind schedule/over budget on 4x 1117 MWe reactors.
- otp124 9y 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.
  - philipkglass 9y 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.
    - otp124 9y ago
      Sounds like a viable model, thanks!
  - acidburnNSA 9y 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.
    - otp124 9y ago
      Interesting. So can the core of uranium weapons be re-used for nuclear reactors? (Assuming there is a big arms reduction event)
      - cperciva 9y 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).