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I think the most legitimate concern about nuclear safety is, what happens to the plant if you push the "OFF" button and go home? The current gigawatt-scale pla

by p1mrx 6y ago

I think the most legitimate concern about nuclear safety is, what happens to the plant if you push the "OFF" button and go home? The current gigawatt-scale plants (AP1000, Hualong One, etc.) can cool without external water for 72 hours, after which a meltdown occurs. NuScale plans to run their reactors at the bottom of a pool, with enough water to passively transition to air cooling over the course of a month. (There are a bunch of proposed reactor designs with similar safety characteristics, but I know more about NuScale because they've been in the news lately.) I'm not against building plants with a 72-hour buffer for now, due to the pressing need for low-carbon energy, but we should really focus our future resources on passive self-cooling designs that we can safely copy-paste across the planet on a massive scale.

thaumasiotes 6y ago
> I think the most legitimate concern about nuclear safety is, what happens to the plant if you push the "OFF" button and go home? Local peasants get in, take some pretty glowing things back home, apply the stuff as makeup, and die horrible deaths. When the family tries to bury their daughter in the town cemetery, the rest of the town marches in protest. Clearly, the lesson is that we should stop building... hospitals. https://en.wikipedia.org/wiki/Goi%C3%A2nia_accident https://en.wikipedia.org/wiki/Goi%C3%A2nia_accident
AI_WAIFU 6y ago
I don't understand who's bright idea it was to use water as the primary coolant for a nuclear reactor. IIRC almost every single major nuclear incident has been caused or dramatically exacerbated by having it boil away or cause a steam explosion or mix with the ground water or chemically react with the fuel rods to produce additional heat and hydrogen gas which also explodes. Like just go through this list and count the number of times water was a good chunk of the problem. https://en.wikipedia.org/wiki/Nuclear_and_radiation_accidents_and_incidents https://en.wikipedia.org/wiki/Nuclear_and_radiation_accident... There are multiple options that don't have this issue. For instance, if you use liquid lead the thing can sit around indefinitely with no active cooling. In fact you have the opposite problem, you need to keep heating the lead to prevent the whole reactor pool from freezing. https://en.wikipedia.org/wiki/Lead-cooled_fast_reactor https://en.wikipedia.org/wiki/Lead-cooled_fast_reactor
- nullc 6y ago
  Water certainly causes trouble. At least they're not cooled by something that explodes on contact with air or water!
- GekkePrutser 6y ago
  Liquid metal reactors also have had their fair share of accidents despite their small presence.
  - AI_WAIFU 6y ago
    Of course, but a liquid lead reactor's failure modes don't usually involve a massive release of radioactivity all over the environment. Absolute worst case you'll get a meltdown and/or a coolant leak. But diligent materials choices should prevent an associated fire or steam explosions that would spread radioactive elements all over the place. This isn't true with all liquid metal reactors though. Liquid sodium reactors have flammable radioactive coolant, and a coolant breach could be environmentally disastrous.

by p1mrx 6y ago

thaumasiotes 6y ago

> I think the most legitimate concern about nuclear safety is, what happens to the plant if you push the "OFF" button and go home? Local peasants get in, take some pretty glowing things back home, apply the stuff as makeup, and die horrible deaths. When the family tries to bury their daughter in the town cemetery, the rest of the town marches in protest. Clearly, the lesson is that we should stop building... hospitals. https://en.wikipedia.org/wiki/Goi%C3%A2nia_accident https://en.wikipedia.org/wiki/Goi%C3%A2nia_accident

AI_WAIFU 6y ago

I don't understand who's bright idea it was to use water as the primary coolant for a nuclear reactor. IIRC almost every single major nuclear incident has been caused or dramatically exacerbated by having it boil away or cause a steam explosion or mix with the ground water or chemically react with the fuel rods to produce additional heat and hydrogen gas which also explodes. Like just go through this list and count the number of times water was a good chunk of the problem. https://en.wikipedia.org/wiki/Nuclear_and_radiation_accidents_and_incidents https://en.wikipedia.org/wiki/Nuclear_and_radiation_accident... There are multiple options that don't have this issue. For instance, if you use liquid lead the thing can sit around indefinitely with no active cooling. In fact you have the opposite problem, you need to keep heating the lead to prevent the whole reactor pool from freezing. https://en.wikipedia.org/wiki/Lead-cooled_fast_reactor https://en.wikipedia.org/wiki/Lead-cooled_fast_reactor

nullc 6y ago
Water certainly causes trouble. At least they're not cooled by something that explodes on contact with air or water!
GekkePrutser 6y ago
Liquid metal reactors also have had their fair share of accidents despite their small presence.
- AI_WAIFU 6y ago
  Of course, but a liquid lead reactor's failure modes don't usually involve a massive release of radioactivity all over the environment. Absolute worst case you'll get a meltdown and/or a coolant leak. But diligent materials choices should prevent an associated fire or steam explosions that would spread radioactive elements all over the place. This isn't true with all liquid metal reactors though. Liquid sodium reactors have flammable radioactive coolant, and a coolant breach could be environmentally disastrous.