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  #1  
Old 07-08-2012, 10:16 AM
Crafter_Man Crafter_Man is offline
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Liquid fluoride thorium reactor

There's a guy named Kirk Sorensen who says we should be using thorium instead of uranium for nuclear power. Is this the answer to our future energy needs?
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  #2  
Old 07-08-2012, 12:59 PM
John H John H is offline
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The way I see things is that thorium is just one more ingredient to pick from in a basket full of various of energy resources.
No carbon and improved safety may make it seem more attractive than uranium or coal.

Here is some back of the envelope data and calculations on a few energy sources. Reserves / energy yield per unit / total energy.
Code:
861,000,000,000 tonnes coal    [        6.7 kWh per kg] 5.7EWh
      2,600,000 tonnes thorium [1,000,000.0 kWh per kg] 2.6EWh
      5,400,000 tonnes uranium [  360,000.0 kWh per kg] 1.9EWh
I'm guessing that the numbers for thorium are much lower than they could be due to lack of demand.
If accessible quantities of thorium could be boosted 10-100x from the numbers here I could see it going from viable resource to possible silver bullet.
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  #3  
Old 07-08-2012, 01:04 PM
Dewey Finn Dewey Finn is offline
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Here is a thread from last year on thorium reactors with some further information from Stranger on a Train and others.
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  #4  
Old 07-08-2012, 02:23 PM
JoelUpchurch JoelUpchurch is offline
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Kirk Sorenson's web site is here: http://energyfromthorium.com/

Thorium reactors are breeders. Thorium by itself is not fissionable, but it can be breed into U-233 which is. Thorium is much more common than Uranium and U-233 is very suitable for weapons compared to U-235 or Pu-239.


India, China and the U.S. are pursuing Thorium technology.

http://www.smartplanet.com/blog/inte...-nuclear/17037
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  #5  
Old 07-09-2012, 09:31 AM
Hari Seldon Hari Seldon is offline
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I cannot understand why no one is pursuing traveling wave reactors: http://en.wikipedia.org/wiki/Traveling_wave_reactor. TWRs not only use the waste from other reactors but produce much more power from the same amount of uranium and the uranium does not have to be enriched. More importantly, the waste products are relatively short-lived radioactives (half lives < 100 years) that do not require long-lasting storage and also would not be targets for terrorists. The only argument against it seems to be that they would have to restart the entire development and environmental studies from the beginning. No mean objection, but maybe it should be done anyway. Certainly so long as the long term storage problem is unsolved.
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Old 07-09-2012, 12:47 PM
JoelUpchurch JoelUpchurch is offline
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Quote:
Originally Posted by JoelUpchurch View Post
Thorium reactors are breeders. Thorium by itself is not fissionable, but it can be breed into U-233 which is. Thorium is much more common than Uranium and U-233 is very suitable for weapons compared to U-235 or Pu-239.
I meant not suitable.
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Old 07-09-2012, 12:59 PM
JoelUpchurch JoelUpchurch is offline
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Quote:
Originally Posted by Hari Seldon View Post
I cannot understand why no one is pursuing traveling wave reactors: http://en.wikipedia.org/wiki/Traveling_wave_reactor. TWRs not only use the waste from other reactors but produce much more power from the same amount of uranium and the uranium does not have to be enriched. More importantly, the waste products are relatively short-lived radioactives (half lives < 100 years) that do not require long-lasting storage and also would not be targets for terrorists. The only argument against it seems to be that they would have to restart the entire development and environmental studies from the beginning. No mean objection, but maybe it should be done anyway. Certainly so long as the long term storage problem is unsolved.

Terrapower is pursuing it. They are currently in negotiations with China to build a prototype there.

http://news.yahoo.com/bill-gates-dev...104529282.html

The TWR would be wonderful for the US, since we large stockpiles of U-238. We could provide power for the next century without mining new fuel.

China does not seem to inclined to put all it's eggs in one basket.
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  #8  
Old 07-10-2012, 07:14 AM
Hari Seldon Hari Seldon is offline
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Quote:
Originally Posted by JoelUpchurch View Post
Terrapower is pursuing it. They are currently in negotiations with China to build a prototype there.

http://news.yahoo.com/bill-gates-dev...104529282.html

The TWR would be wonderful for the US, since we large stockpiles of U-238. We could provide power for the next century without mining new fuel.

China does not seem to inclined to put all it's eggs in one basket.
I read that article, thanks for the link. It still sounds like something maybe 20 years in the future, but it would be a vast improvement. Considering all the money thrown at fusion power with not much to show for it, it is about time. I suppose there would be some unexpected downsides--there always are--but it is hard to see how it wouldn't be a serious improvement over current generations of fission reactors.

Just as an aside, I don't understand why Microsoft is still considered "The evil empire". At least Gates is using his billions to some purpose.
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