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Small nuclear reactors: tiny NuScale reactor gets safety approval

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Re: Small nuclear reactors: tiny NuScale reactor gets safety approval

#81

Post by core-questions »

isatty wrote: post #13
core-questions wrote: post #9

Earlier quoted context omitted.

What a bad faith post. > Three Mile Island Was handled reasonably well, resulted in safety improvements to procedures and designs for future reactors. From https://www.nrc.gov/reading-rm/doc-collections/fact-sheets/3... > The approximately 2 million people around TMI-2 during the accident are estimated to have received an average radiation dose of only about 1 millirem above the usual background dose. To put this int…

> Accident caused by Communists who did not care about what happened to Ukrainians There were many such RBMK reactors spread all over the Soviet world that had the same flaws . There are many problems with your summary so can I just recommend that you watch the HBO mini series "Chernobyl" instead? It's a great watch.

Flaws? The meltdown was caused by a deliberate action on behalf of people with control of the plant.

I haven't watched Chernobyl because I prefer to not get my history from television shows with a narrative axe to grind.

Re: Small nuclear reactors: tiny NuScale reactor gets safety approval

#82

Post by jabl »

petre wrote: post #60
adrianmonk wrote: post #41

Earlier quoted context omitted.

Maybe tiny refers to the power output. The article says it makes 50 megawatts. Compare that to a nuclear plant near me which has two reactors that each generate 1280 megawatts. So it would take about 25 of these to equal the power output of a traditional nuclear reactor.

Yes but it's inherently safer. Utility scale nuclear was scaled up from naval reactors which are smaller, use highly enriched uranium as opposed to LEU and are safer. Alvin Weinberg, the father of several LWR designs cautioned about the safety of utility scale reactors (17:51): https://youtu.be/EviEN0ScOwg The NuScale design also uses LEU and a plant is comprised of up to 12 of these modules sitting in water pools. Y…

To nitpick, some naval reactors are designed to use LEU. E.g. French submarines run on 7% enriched fuel. And reportedly Chinese subs also use LEU.

Re: Small nuclear reactors: tiny NuScale reactor gets safety approval

#83

Post by godelski »

vlovich123 wrote: post #65
xigency wrote: post #59

Earlier quoted context omitted.

If you consider the climate, about 100 times that.

Is there a paper on that? 40 trillion sounds like a lot and I’m curious how that number is generated.

I can't think of a specific paper/s off hand but having been at labs where they do climate modeling and going to every talk I could I've heard estimates of tens of trillions to hundreds. So the ballpark at least passes my sniff test, though I know that this isn't a hard source. It is also difficult to estimate the damages and costs of climate change which is part of why costs vary so widely. (e.g. do you include events like Katrina?)

Re: Small nuclear reactors: tiny NuScale reactor gets safety approval

#84

Post by core-questions »

m0zg wrote: post #31
core-questions wrote: post #9

Earlier quoted context omitted.

What a bad faith post. > Three Mile Island Was handled reasonably well, resulted in safety improvements to procedures and designs for future reactors. From https://www.nrc.gov/reading-rm/doc-collections/fact-sheets/3... > The approximately 2 million people around TMI-2 during the accident are estimated to have received an average radiation dose of only about 1 millirem above the usual background dose. To put this int…

> Communists who did not care about what happened to Ukrainians They didn't really care what happened to _anybody_, not just Ukrainians. Ukrainians (as well as about 30% of Russians) just happened to live in that particular location. The plume made it all the way to the Nordics and Germany, and I, as a kid, had to take iodine tablets in Russia, even though officially everything was "under control" for a few days. The…

Good point, I agree entirely. It's clear that nuclear power needs to be under the control of responsible governments, built in safe locations (i.e. not on fault lines, not in tsunami zones), and needs solid maintenance budgets.

All of these things are solvable problems, but if we don't solve them before all the current nuclear plant techs age out, we won't be able to apprentice people and keep the culture of solid maintenance alive. At that point, they really do become an albatross.

Re: Small nuclear reactors: tiny NuScale reactor gets safety approval

#85

Post by adammunich »

jhallenworld wrote: post #52

Here is the NRC website about this reactor: https://www.nrc.gov/reactors/new-reactors/smr/nuscale.html Here is an interesting sub-report: https://www.nrc.gov/docs/ML2022/ML20224A525.pdf Information withheld for security reasons. One item concerns the "ultimate heat sink". What happens when the ultimate heat sink is lost? Well a design assumption is that it is not lost: https://www.nrc.gov/docs/ML2020/ML20205L410.pdf…

It's really hard to comprehend just how much heat a reactor can make from decay alone. Like... boiling a hot tub in only a minute.

Re: Small nuclear reactors: tiny NuScale reactor gets safety approval

#86

Post by marshray »

godelski wrote: post #64
marshray wrote: post #42

I think it's disingenuous to argue the economics of nuclear without mentioning: "DOE reported that it faced an estimated $494 billion in future environmental cleanup costs — a liability that roughly tripled during the previous 20 years." https://www.gao.gov/assets/700/696956.pdf

My understanding is that these DoE sites are weapon sites, such as Hanford. These are a different ball game than power plants. They use different technologies and have different kinds of waste. Sure apples and oranges are both round fruits, but aren't one to one comparisons. List of sites https://www.dnfsb.gov/doe-sites

"In 2015, President Obama found that a separate repository for defense-related radioactive waste was required. DOE reported that defense waste is smaller in volume, less radioactive, and thermally cooler than commercial spent nuclear fuel, stating that a defense repository may be easier to develop."

https://www.gao.gov/key_issues/disposal_of_highlevel_nuclear...

Re: Small nuclear reactors: tiny NuScale reactor gets safety approval

#87

Post by ogre_codes »

vlovich123 wrote: post #65
xigency wrote: post #59

Earlier quoted context omitted.

If you consider the climate, about 100 times that.

Is there a paper on that? 40 trillion sounds like a lot and I’m curious how that number is generated.

Million acre forest fires are expensive to deal with. Likewise, drought, relocating billions of people displaced by sea level increase. Might be an under-estimate.

Re: Small nuclear reactors: tiny NuScale reactor gets safety approval

#88

Post by dodobirdlord »

marshray wrote: post #67
RhodesianHunter wrote: post #58

Earlier quoted context omitted.

This is IMO a positive for nuclear, not a negative. You're forced to confront the cleanup as opposed to fossil fuels, where you just blow your waste out into the atmosphere and make it the commons' problem.

If only a method for permanent disposal of nuclear waste actually existed.

The world is filled with naturally occurring phenomena far more dangerous than a big pile of low-grade nuclear waste. The really dangerous stuff ceases to exist after a few decades of sitting in a cooling pond, and then what’s left has such a long half life that it’s not particularly threatening. Water is an incredible radiation dampener, and the ocean is already chock full of dissolved uranium. The only reason we don’t just toss our low-grade fission waste into an oceanic trench somewhere is that it’s valuable and wherever we put it we know we’ll probably change our minds and want it back for reprocessing at some point.

Re: Small nuclear reactors: tiny NuScale reactor gets safety approval

#89

Post by Retric »

xigency wrote: post #68
vlovich123 wrote: post #65

Earlier quoted context omitted.

Is there a paper on that? 40 trillion sounds like a lot and I’m curious how that number is generated.

If you could solve climate change for less than that, I think it would be splendid. To put that number in context, which is just an order of magnitude, it's $5,000 for every person on Earth, about 1.5x the current US national debt, and just under the combined market cap of NYSE+NASDAQ. As an existential problem for humanity that doesn't currently have a solution, I think that's a decent cost estimate.

Climate change his hardly an existential threat for humanity. We survived the last ice age with stone tools, this is a less severe change. Economic impacts from things like rising sea levels really depend on how much we spend on maintaining things as they currently are vs adapting to the new normal.

Aka do you live below sea level, raise the city, or move somewhere else. https://en.wikipedia.org/wiki/Raising_of_Chicago

Re: Small nuclear reactors: tiny NuScale reactor gets safety approval

#90

Post by manfredo »

marshray wrote: post #42

I think it's disingenuous to argue the economics of nuclear without mentioning: "DOE reported that it faced an estimated $494 billion in future environmental cleanup costs — a liability that roughly tripled during the previous 20 years." https://www.gao.gov/assets/700/696956.pdf

Is this the cleanup cost for civilian power generation? Or for military reactors and nuclear weapons, too? Because all the nuclear waste from civilian power generation occupies a volume the size of a football field in footprint and less than 10 yards high. https://www.energy.gov/ne/articles/5-fast-facts-about-spent-...
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