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China to Build Thorium Molten-Salt Reactor in 2025

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Re: China to Build Thorium Molten-Salt Reactor in 2025

#131

Earlier quoted context omitted.

Isn't thorium also pretty abundant? Judging by this, the US has around six times as much thorium as uranium: https://en.wikipedia.org/wiki/List_of_countries_by_uranium_r... https://en.wikipedia.org/wiki/List_of_countries_by_thorium_r... I've also never really gotten the proliferation concern. I mean, sure, you don't want to sell a breeder reactor to Iran. But why can't you sell one to PG&E? Are we that concerned that…

> Isn't thorium also pretty abundant? Yes. Even more so! But that doesn't mean it's easy to get. Everything has to be processed at the end of the day. The reason I brought up uranium is that it is easier to fissile. So sure, there's more thorium but it requires more processing. Why use it when we aren't concerned about uranium access? Uranium is already "cheap". (We could get into an analogy with different types of o…

> But what I wanted to combat is the misinformation that thorium __can't __ be used for proliferation

Nobody serious is actually saying that.

What people are actually saying that any nation would be completely fucking insane to attempt to start their nuclear program with this method. When there are proven method that already work, are far easier and with existing equipment.

Plus, using U233 also leads to the creation of elements that you really don't want and are unpractical for a long term nuclear defense policy. And they are equally as unpractical for hiding nuclear material.

No country so far has used this method for a reason, and no country will either. And that argument doesn't matter for most western nations anyway.

> We can dramatically reduce waste but we don't.

Lots of things aren't done until they are done. We should and with a cyclical thorium fuel cycle we could.

While nuclear waste isn't a real problem, we still have millions of people who think it is, and to have clear solution that anybody can just point out, is much better of an argument winner then 'just ignore the waste its fine'. Even if it is actually fine.

> There just isn't much of it and doing more fission is less economical.

Not sure what you mean. I don't think its actually true that fission isn't economical specially if you are thinking about it from a country perspective.

I did some calculation with pretty conservative assumptions for cost, using Germany at the start of the 'Grünewende' and the cost of all that. And I think nuclear would have been a far better deal for them, and its not even really close.

> That's the case with France, so they "recycle" their waste and in the process this dramatically reduces it.

They are using a very complex process. Part of the reason why in the 60s some of the smartest minds looked into molten salt is because that's in many ways easier to work with then complex solid fuels.

> So that points us back to the opening: yes, thorium is abundant, but why go through all that effort when we got plenty of uranium which is cheap and efficient?

In general you are right but a few points, uranium isn't actually that cheap. We restrict what our reactors can do because only low enriched is commercially available, limiting some of the cool things we could be doing. Enriched uranium was artificially cheap because of Russian policy. And now to supply enough, the West will need to increase its own enrichment again.

Second, its only not a big factor of the cost because PWR plants have pretty high operating cost. If you can get the labor cost down, the capital cost down, and the maintenance cost down, and the fuel cost down, you have something potentially interesting.

This of course matters far more when you are doing this as a country strategically. For an individual plant or company its not worth doing.

The things that actually makes thorium special, and an actual improvement over uranium is that you can do a thermal breeder.

Re: China to Build Thorium Molten-Salt Reactor in 2025

#132
The reason the United States pretends like it doesn't have plenty of rare Earth metals, is because of the insane anti-nuke cult that causes you to have to discard thorium as if it was a dangerous waste. Thorium is usually co-deposited with rare earths. So nobody in the United States or Canada can afford to mine or process rare earths because they can't afford to dispose of bananas. Or Rather thorium which has the same radioactivity as a banana.

Re: China to Build Thorium Molten-Salt Reactor in 2025

#133
post #93

Earlier quoted context omitted.

>A declassified 1966 memo from the US nuclear program stated that uranium-233 has been shown to be highly satisfactory as a weapons material (wikipedia https://en.wikipedia.org/wiki/Uranium-233#Weapon_material )

From the same article, apparently the infeasiblity is that pure uranium-233 could work, but a normal breeder reactor would also produce a small amount of uranium-232, which is fine for power reactors but not bombs. If you have the resources of the US DoD then you can design a special breeder reactor that uses special thorium, but by that point you could just make one that breeds plutonium out of uranium too.

Although in theory a U-233 bomb would work just fine, the fact is that very few U-233 bombs were ever made. I don't think that more than 10, by all the nuclear powers combined. One way or another U-233 is not as good a bomb-making material in practice as it is in theory.

Re: China to Build Thorium Molten-Salt Reactor in 2025

#134
post #43

Earlier quoted context omitted.

They don't want to what? Don't want to give up poorly designed regulations? Or do not want nuclear power? The latter is largely due to the anti nuclear movement, as sponsored by the petroleum industry. This will go down in history as one of the biggest self-owns in trying to protect the environment. https://www.forbes.com/sites/kensilverstein/2016/07/13/are-f...

Dont want to be scared of a nuclear meltdown

We should put a stop to hydro electric as well https://en.m.wikipedia.org/wiki/1975_Banqiao_Dam_failure

Re: China to Build Thorium Molten-Salt Reactor in 2025

#135

Earlier quoted context omitted.

> Isn't thorium also pretty abundant? Yes. Even more so! But that doesn't mean it's easy to get. Everything has to be processed at the end of the day. The reason I brought up uranium is that it is easier to fissile. So sure, there's more thorium but it requires more processing. Why use it when we aren't concerned about uranium access? Uranium is already "cheap". (We could get into an analogy with different types of o…

> But what I wanted to combat is the misinformation that thorium __can't __ be used for proliferation Nobody serious is actually saying that. What people are actually saying that any nation would be completely fucking insane to attempt to start their nuclear program with this method. When there are proven method that already work, are far easier and with existing equipment. Plus, using U233 also leads to the creation…

  > Nobody serious is actually saying that.

  > any nation would be completely fucking insane to attempt to start their nuclear program with this method
To quote acidburn[0] who's quoting Livermore designers[1]

  | "If today's weapons were based on U-233, [we] would have no interest in switching to plutonium"

  > then 'just ignore the waste its fine'
Who said this?

I said

  >> You also can use similar technologies as thorium would need with uranium and still reduce waste.
I said that you can already do this

  > have clear solution that anybody can just point out
You have those solutions exist without Thorium. I even mentioned the French. And you even replied to that. Thorium is not at commercial level, so if you're going to compare research technology, be aware of the other research technology.

[0] https://news.ycombinator.com/item?id=42558370

[1] (pdf, it's on the last page) https://www.osti.gov/servlets/purl/79078

Re: China to Build Thorium Molten-Salt Reactor in 2025

#136
post #134

Earlier quoted context omitted.

Dont want to be scared of a nuclear meltdown

We should put a stop to hydro electric as well https://en.m.wikipedia.org/wiki/1975_Banqiao_Dam_failure

Dont let the voters know about this or we will

Re: China to Build Thorium Molten-Salt Reactor in 2025

#137
post #109

Earlier quoted context omitted.

> the prosperity afforded by abundant energy is a problem they're supposed to be solving. What does this mean? Did you misplace a word somewhere? Why would prosperity be a problem?

The way I read it is that the amount of energy available for direct use translates directly to the quality of life. The more energy they have, the more they can do with it. Plus if it’s clean and readily available. Instead of being world’s factory for garbage, or figuring out how to invade Taiwan, figure out how to supply clean, “reasonably cheap” nuclear energy.

Any nation with effectively unlimited energy will develop directed energy weaponry.

Re: China to Build Thorium Molten-Salt Reactor in 2025

#138
post #127

Earlier quoted context omitted.

I dispute that. I'm as pro-nuclear as one can be, but I don't think the NRC (Nuclear Regulatory Commission) is doing a bad job, or that the regulations are unreasonable. In the end, a lot of the regulations came as a response to incidents like Three Mile Island, Chernobyl and Fukushima, and others less well known. One way or another, nuclear reactors are extremely complex machines, with numerous failure modes. As var…

Which part of the linked article do you dispute?

I was replying to the parent comment: "The economics of nuclear power is dominated by a poorly designed regulatory environment".

Re: China to Build Thorium Molten-Salt Reactor in 2025

#139
post #127

Earlier quoted context omitted.

Which part of the linked article do you dispute?

I was replying to the parent comment: "The economics of nuclear power is dominated by a poorly designed regulatory environment".

That is understood. The comment had a well written article that goes into detail about how the poorly designed regulations more than double the costs of building nuclear. Just saying you dispute something, without providing any arguments, or rebuttals is not very convincing.

Re: China to Build Thorium Molten-Salt Reactor in 2025

#140
post #139

Earlier quoted context omitted.

I was replying to the parent comment: "The economics of nuclear power is dominated by a poorly designed regulatory environment".

That is understood. The comment had a well written article that goes into detail about how the poorly designed regulations more than double the costs of building nuclear. Just saying you dispute something, without providing any arguments, or rebuttals is not very convincing.

I provided arguments: a lot of the regulations came in response to new failure rates discovered when operating nuclear reactors, many times via an accident like Fukushima.

But since you are asking, here's a typical statement from the linked article:

  > Nuclear grade components don’t necessarily have higher performance requirements than conventional components - the cost instead mostly comes from the documentation and testing to ensure they’ll meet their performance requirements.
This seems like an example of "bad regulation". But it's not, it's actually good regulation. If you have 2 components with the same level of performance, and one has more strict documentation and testing, it does not mean they are interchangeable. The one with more testing is much less likely to fail, and this is quite important for a nuclear reactor. Would you dispose with this regulation?

Now consider this: the NRC approved the NuScale reactor design [1]. Yet, NuScale never built a demonstration reactor, the entire approval was based on computer models. A regulatory body hell-bent to stymie new reactors would not have done that. This approval, in my mind, shows that the NRC is quite reasonable.

And by the way, I did spend some time going over some of the approval documents. I remember a dissension paper that I found, where one NRC inspector expressed dissatisfaction with some corner case concerning borated water. I can't find it now, but I found some paragraphs in one of the final documents, where the NRC describes the situation ([2] page 48):

  > The applicant also analyzed postulated scenarios involving extended DHRS operation with the secondary side water level in the steam generator tubes above the primary side water level in the reactor vessel downcomer, hereafter referred to as the boiling/condensing heat transfer mode. In this scenario, the boiling of borated primary coolant in the reactor core generates steam, which subsequently condenses on the section of the steam generator tubes that is filled with secondary coolant and above the downcomer water level. The resulting formation of condensate, if left unmitigated, would tend to dilute the boron concentration of the coolant in the downcomer.
The document then goes on to show that NuScale performed some analysis that eventually satisfied the NRC.

NuScale spent a lot of money and man-hours (if I remember correctly $0.5 BN and 1.5 million man-hours) in order to secure the approval. But reading the approval documents on the NRC website, you get the idea that all the work was actually needed. Reactors are just very complex machines with many failure modes.

[1] https://www.nrc.gov/reactors/new-reactors/smr/licensing-acti...

[2] https://www.nrc.gov/docs/ML2020/ML20205L408.pdf

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