Thorium alternative to nuclear fuel

[encorp]

http://www.ted.com/talks/kirk_sorensen_thorium_an_alternative_nuclear_fuel.html

I was impressed by the video; but I was left thinking "What are the downsides?" and "so why haven't we done this already?" - and as such I feel like there's something missing here.

Could anyone with more knowledge on the matter explain to me in layman terms as to why this is not how we get our power?


-Cam

 

[QuantumPion]

The obstacles are:
1) lack of experience in materials that can handle molten salts at high temperatures for long periods of time
2) safety issues with circulating liquid fuel and fission product barriers to prevent release
3) safety issues with circulating liquid fuel and reactivity control
3) requirement to use high enriched uranium/plutonium
4) requirement to have on-site reprocessing (proliferation risk)
5) NRC inability to consider alternative nuclear technology that falls outside of their PWR/BWR pigeonhole

That being said I like the idea and hope the technology will make a comeback in the future.

 

[encorp]

Thanks for your reply.

(Also, apologies for posting in the wrong forum. My mistake. Thanks mods, for moving.)

I can see how most of those issues could be addressed fairly easily over time, except maybe the proliferation (4) one.

 

[IttyBittyBit]

QuantumPion, all except 3 and 4 are valid. These are addressed in Sorensen's talks.

The most valid point here is 1, and it was one of the difficulties of the MSRE experiment. At the time graphite was used but today we have much better materials such as copper-reinforced graphite fiber.

There is no reason why it wouldn't work, imo. Sorensen's company, Flibe energy, is undertaking research to see if it can make the LFTR a reality. India is also doing a lot of research seeing as they have a lot of natural thorium deposits.

 

[encorp]

Wonderful, that seems a bit less doom and gloom.

I don't expect technology like this to save the world so to speak, but if there ever was a time we needed it most.. I'd saw now and the near future for sure!

Thanks Itty!

 

[wizwom]

As far as Thorium qua Thorium goes, the ACR is designed to use partial thorium bundles. I don't know that anyone has started using them, but the designs and the testing have been done.
The Chinese are actively pursuing building a full demo LFTR. They are not joking about it, and are putting real money into it.
The Indians have Thorium breeders in build phase, designed to each service 7 more conventional PWR plants. That, BTW, is a huge breeding rate, which Thorium can easily service from a thermal reactor.

One of the issues in the US is that solid Thorium breeders would require a reprocessing facility, and the US model of fissile control is incredibly inefficient at that, and politically the DOE and NRC aren't about to give up any control, no matter how nonsensical it is to maintain it.

So rare Earth mines in the US set aside thousands of tonnes a year of high-grade rare Earth ore because it includes Thorium, because the exploitation of any of it would concentrate the ore tailings above the threshold and be extremely expensive in terms of regulatory cost.