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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

#101

Post by godelski »

acidburnNSA wrote: post #71
marshray wrote: post #67

Earlier quoted context omitted.

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

There are good permanent disposal methods available. The deep geologic repository under construction in Finland is probably the best example. More info here: https://whataboutthewaste.com People use "what about the waste" as a reason to not use nuclear. Yet, fossil and renewable biofuel waste is (as mentioned) just dumped into the biosphere where it ends and estimated 8 million lives early per year, according to the…

Not to mention the waste associated with semi-conductors. Long term waste is not just a problem associated with nuclear. It is also worth mentioning that the major waste issues are associated with DoE weapon sites and not as much power sites.

I would also encourage other's to click on acidburnNSA's profile as this is where their expertise lies and they have written extensively (with plenty of links) on the subject.[0]

[0] https://whatisnuclear.com/waste.html

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

#102

Post by manfredo »

e12e wrote: post #75
acidburnNSA wrote: post #71

Earlier quoted context omitted.

There are good permanent disposal methods available. The deep geologic repository under construction in Finland is probably the best example. More info here: https://whataboutthewaste.com People use "what about the waste" as a reason to not use nuclear. Yet, fossil and renewable biofuel waste is (as mentioned) just dumped into the biosphere where it ends and estimated 8 million lives early per year, according to the…

Unfortunately that doesn't quite solve the problem of getting waste from reactor to storage site.

Getting the waste to a storage facility is very easy. You put it on a semi trailer and move it to the storage site: http://large.stanford.edu/courses/2015/ph241/avery-w2/images...

Nuclear waste is radioactive, but not so radioactive that it's unsafe to stand next to a container. Most waste is stored on site.

It actually doesn't make sense to move nuclear waste to permanent storage because some reactor designs can use this waste as fuel.

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

#103

Post by ColanR »

natcombs wrote: post #100
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…

>> What happens when the ultimate heat sink is lost? What's an example event where the ultimate heat sink might be lost?

No expert, but if it's a pool of water then an earthquake might cause a leak?

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

#104

Post by jabl »

rubber_duck wrote: post #34
nickik wrote: post #27

As a huge fan of nuclear power, I never felt like NuScale style 'SMR' were all that great of an idea. Yes, it gains you some of the economics of factory construction and that you can start small and scale a location, but on the other side you lose that again because you lose the economics of scale that traditional PWR gets. I really believe we should be a nuclear society by now, and that regulations both around react…

>Yes, it gains you some of the economics of factory construction and that you can start small and scale a location, but on the other side you lose that again because you lose the economics of scale that traditional PWR gets. You mean they lose operational efficiency ? Economies of scale come from the ability to mass produce. You forgot to mention the largest differentiator - eliminates the possibility of a global cat…

> You mean they lose operational efficiency ?

Historically, one of the few successful ways to lower the price per generated power from a nuclear power plant has been to make the reactor larger. So yeah, there's a reason why the latest traditional PWR designs such as the French EPR are huge (1600 MWe).

The gamble with these small reactors like Nuscale is that series production of the reactors in a factory would make up for the loss of the traditional economy of scale due to size. It remains to be seen how well that will work out.

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

#105

Post by manfredo »

marshray wrote: post #86
godelski wrote: post #64

Earlier quoted context omitted.

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...

But crucially, commercial spent nuclear fuel is in containers. Spent waste from weapons development was often just dumped in a pit and buried. Our priorities were very different in the 1940s and 50s. Seriously look at this picture [1]. That encapsulates the attitude towards nuclear safety during the early cold war. The soviets just dumped their waste into a lake [2]. Not to mention we detonated a thousand or so nuclear bombs, many of them above ground.

1. https://en.m.wikibooks.org/wiki/History_of_Nevada/Nevada_and...

2. https://en.m.wikipedia.org/wiki/Lake_Karachay

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

#106

Post by marshray »

erentz wrote: post #77
nickik wrote: post #70

Earlier quoted context omitted.

It disingenous of you to argue that all DoE cost from the last 60 years have any implication on a modern nuclear site build. When nuclear started they had no idea how to do things and had to do a lot of things very fast. The waste majority of those cost are not because of civilian nuclear reactor, but rather creation of nuclear weapons. Site cleanup cost are a factor, but not a huge one considering a site can be acti…

Yes. It appears to very explicitly is about DOE sites, national labs with waste dating back to the Manhattan project and Cold War. This figure would seem to be better described as the clean up cost for our nuclear weapons programs with maybe a small side dish of reactor research in places like INL.

The defense waste is just a fraction of the total:

"The U.S. commercial power industry alone has generated more waste (nuclear fuel that is "spent" and is no longer efficient at generating power) than any other country—nearly 80,000 metric tons. This spent nuclear fuel, which can pose serious risks to humans and the environment, is enough to fill a football field about 20 meters deep. The U.S. government’s nuclear weapons program has generated spent nuclear fuel as well as high-level radioactive waste and accounts for most of the rest of the total at about 14,000 metric tons, according to the Department of Energy (DOE). For the most part, this waste is stored where it was generated—at 80 sites in 35 states. The amount of waste is expected to increase to about 140,000 metric tons over the next several decades. However, there is still no disposal site in the United States."

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

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

#107

Post by jessaustin »

sarcasmatwork wrote: post #4

fyi, OSU college has a 1-megawatt research reactor. https://www.oregon.gov/energy/facilities-safety/facilities/P... https://www.corvallisadvocate.com/2012/got-nuke-state-of-the...

Mizzou has a 10MW:

https://www.murr.missouri.edu/

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

#109

Post by manfredo »

Retric wrote: post #89
xigency wrote: post #68

Earlier quoted context omitted.

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_Chica…

The last ice age occurred gradually over the span of millennia. Anthropic climate change is occurring in an instant by comparison. Not to mention, humanity survived by mass migration, something that's a lot harder for integrated global economies to do. Few believe humanity is going to go extinct. But extinction of industrialized civilization is a more real concern. And the collapse of industrialized civilization will undoubtedly entail the death of over 90% of the human population.

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

#110

Post by ethbr0 »

manfredo wrote: post #98
marshray wrote: post #76

Earlier quoted context omitted.

That option doesn't exist in the US. We have no permanent disposal facilities, not even in the planning stage. https://www.gao.gov/key_issues/disposal_of_highlevel_nuclear...

We do have a permanent disposal facility built, but congress chose to forbid its operation. This is a self inflicted problem: we don't have a permanent disposal facility because we refuse to use the permanent disposal facility we built. https://en.m.wikipedia.org/wiki/Yucca_Mountain_nuclear_waste...

FYI, to the ready point, as Wikipedia notes: "The DOE was to begin accepting spent fuel at the Yucca Mountain Repository by January 31, 1998 but did not do so because of a series of delays due to legal challenges, concerns over how to transport nuclear waste to the facility, and political pressures resulting in underfunding of the construction."

The anti-waste-disposal crowd in the environmental movement feels exceedingly disingenuous.

The amount of goal post moving they've engaged in over the decades makes it clear that their actual goals are to prevent any waste disposal site from being constructed, rather than specific, actionable complaints.

Which is insane, from a net-benefit perspective, as the alternative is to leave nuclear waste dispersed around the country, closer to population centers.

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