Small nuclear reactors: tiny NuScale reactor gets safety approval

Re:Small nuclear reactors: tiny NuScale reactor gets safety ... by phkahler on Thursday September 03, 2020 @05:17PM (#24369002)

Great, and ideally gravity can be used to move it. Remember, at Fukushima power to the pumps was lost.

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Re:Small nuclear reactors: tiny NuScale reactor gets safety ... by AngryData on Thursday September 03, 2020 @07:34PM (#24370069)

It also helps to not be running a reactor based on designs from the 1950s and then decades later ignore all the known potential problems.

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Re:Small nuclear reactors: tiny NuScale reactor gets safety ... by _jal on Thursday September 03, 2020 @07:46PM (#24370163)

It does, but it makes sense to explore fail-safe designs.

Depending on a lack of incompetence in dangerous systems works until it doesn't. To the extent that these things can simply halt when incompetently managed, they should.

If anyone disagrees, I'd like to know why they think the next hundred years are going to be so much freer of political shortsightedness and corruption than the last hundred.

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Re:Small nuclear reactors: tiny NuScale reactor gets safety ... by cameldrv on Thursday September 03, 2020 @08:36PM (#24370536)

Fukishima is a perfect example. Unit 1 had been retrofitted with an isolation condenser, which should have been able to prevent a meltdown even with no power, but it wasn't activated, for reasons that remain murky.

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Re:Small nuclear reactors: tiny NuScale reactor gets safety ... by Gravityloss on Friday September 04, 2020 @04:33AM (#24372971)

https://en.wikipedia.org/wiki/Isolation_condensor

Sounds like a quite simple design indeed, and only one valve opening away from use?

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Re:Small nuclear reactors: tiny NuScale reactor gets safety ... by URSpider94 on Friday September 04, 2020 @12:22AM (#24371688)

Nothing has to move it. It’s in a pool and always there. The pool is big enough to sink all of the decay heat of the reactors it hosts, without needing a refill or heat exchange.

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Re:Small nuclear reactors: tiny NuScale reactor gets safety ... by asdfman123 on Thursday September 03, 2020 @05:55PM (#24369329)

The article states the whole reactor will be submerged in a pool of water, making it passively safe.

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Re:Small nuclear reactors: tiny NuScale reactor gets safety ... by meepmorp on Thursday September 03, 2020 @06:43PM (#24369695)

Reactor cores continue to produce waste heat when shut down, and water evaporates. It’s passively safe till you run out of coolant, then it’s actively dangerous.

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Re:Small nuclear reactors: tiny NuScale reactor gets safety ... by ixfo on Thursday September 03, 2020 @07:03PM (#24369837)

In this case the pool boils off slowly enough from thermal load to let decay heat reduce to the point where air cooling is adequate. So it remains passively safe unless there is a sudden loss of water from the pool.

Engineering a very resilient pond does not feel like as complex a problem as engineering highly complex cooling systems to be resilient.

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Re:Small nuclear reactors: tiny NuScale reactor gets safety ... by throwaway0a5e on Thursday September 03, 2020 @07:48PM (#24370175)

And if you size the pool right it will by cool before the pool boils off. It's simple math and engineering.

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Re:Small nuclear reactors: tiny NuScale reactor gets safety ... by garmaine on Thursday September 03, 2020 @05:59PM (#24369363)

The reactor is submerged in the pool. It’s a passive design.

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Re:Small nuclear reactors: tiny NuScale reactor gets safety ... by tpxl on Thursday September 03, 2020 @05:47PM (#24369253)

Afaik some reactor designs drop the core in a tank below in case of emergency.

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