Please write to your elected representatives and urge them to take action to prevent the destruction of this valuable material.
From the EFT blog:
Saturday, August 08, 2009
Save the Uranium-233!
The Department of Energy has been engaged in a terrible effort to destroy--permanently--what might be the most precious substance on Earth: Uranium-233.
Why is uranium-233 so precious? Because in a liquid-fluoride thorium reactor, U-233 represents essentially unlimited energy. How can that be so? Because in a LFTR, U-233 "catalyses" the consumption of thorium, which is natural and abundant. Every kilogram of U-233 represents roughly a megawatt of power in a LFTR--forever.
This might sound like some kind of "perpetual motion" machine, but it's very much grounded in nuclear reality. U-233 is what thorium turns into when exposed to neutrons. U-233 is fissile, thorium is not. But thorium can capture the neutrons from fissioned U-233 and then replace the U-233 consumed.
So a LFTR, started on U-233, will burn through its original "start charge" fairly quickly, but will continue to form new U-233 at the same rate it's consumed. So after 1, 10, or 100 years, the same amount of U-233 is there as was there when the reactor got started.
That's how U-233 "catalyses" unlimited energy production from thorium.
Here's some images describing the inventory of U-233 that the DOE currently has at Oak Ridge National Lab.
One kilo of U-233 in a LFTR for a year: one megawatt*year (8,760,000 kilowatt*hours)One kilo of U-233 in a LFTR for 10 years: ten megawatt*years (87,600,000 kilowatt*hours)
One kilo of U-233 in a LFTR for 100 years: 100 megawatt*years (876,000,000 kilowatt*hours)
The longer you use U-233, the more it's worth. Let's say electricity sells for a nickel per kW*hr.
One kilo, one year: half a million dollars.
One kilo, ten years: 5 million dollars.
One kilo, one hundred years: 50 million dollars.
Anyone else know of something worth $50M per kg?
But the DOE is determined to destroy this precious resource (and we have about 1000 kg of U-233) by mixing it with U-238 and making it worthless for future use. What's worse, they're spending hundreds of millions of dollars to make this precious resource into waste!
Why are we sabotaging our future by destroying U-233?
Call your congressman (especially if you live in Tennessee) and beg them to intervene!
Further discussion on the thorium-forum on this topic.
Wednesday, August 12, 2009
Why Should We Save the Uranium-233?
I have appealed many times on this blog to our public leaders to save the precious resource that is uranium-233. I have explained in an earlier blog post why the uranium-233, if used in a liquid-fluoride thorium reactor (LFTR) represents "unlimited" energy, because it can "catalyze" the consumption of abundant natural thorium and the inventory of U-233 remains even at the end of the reactor lifetime.
But why save this particular 1000 kg of U-233? If we're going to start hundreds of LFTRs, there isn't enough U-233 to start all of them, and we'll have to use other sources of fissile material. So why worry about this batch of U-233?
Reason #1: Destroying the U-233 is a waste of money.
The Department of Energy is estimating that the cost of "downblending" U-233 with depleted uranium (predominantly U-238) followed by "disposal" at the Waste Isolation Pilot Plant (WIPP) in New Mexico will cost approximately $380 million dollars. This is the estimate as of December 2006, and it came from an article in the Knoxville News-Sentinel that is no longer available, but the text can be viewed on the thorium-forum. $380 million is a LOT of money, money that's being used to destroy U-233 rather than develop the LFTR technology that turns it into unlimited energy.
Reason #2: LFTR runs better when it is started with U-233 than any other fissile fuel.
The LiF-BeF2 dissolves uranium better than plutonium, and if you start LFTR on U-233 you start it the way that it will be running in the long run. It takes a lot of neutron absorptions for U-233 to turn into something other than uranium. You have absorb one (U-234), two (U-235), three (U-236), and finally four (U-237, decaying to Np-237) neutrons before you form your first transuranic nuclide. By contrast, if you were to start LFTR on highly-enriched uranium (which would be a very attractive way to dispose of HEU that was produced for nuclear weapons) you only have to absorb two neutrons to get to Np-237. Plus, HEU has a certain amount of U-238 in it, and U-238 is only one neutron absorption away from forming a transuranic isotope (Pu-239). Obviously starting on plutonium, you've already put a lot of transuranics in the reactor to begin with.
This may sound a bit confusing, so I've made an image to try to graphically depict what happens in the reactor when you start on different fuels. U-233 fissions more favorably, its products have more opportunities to fission, and it has further to go before it forms a transuranic.
Reason #3: U-233 allows us to prove "thorium burning" in a prototype reactor.
One of the basic underlying assumptions of the LFTR is that we can "burn" thorium, in other words, we produce enough U-233 to replace that consumed. By starting a prototype reactor on U-233, we can actually show this in a real-world case early on, rather than trying to extrapolate backwards from a HEU or plutonium startup. It is going to be important to demonstrate that LFTR can really burn thorium, and a U-233 start is the only conclusive way to demonstrate this.
Reason #4: The aged U-233 contains valuable decay products that could save lives.
The U-233 in the DOE's inventory has had 30+ years to decay. That means that some special isotopes like actinium-225 and bismuth-213 have had time to form in the stored U-233. These actinides, which can ONLY be formed through U-233 decay (not fission) have shown that they could be very promising isotopes for certain types of radiotherapies that could save thousands of lives every year. Even the Inspector General of the DOE has appealed to save the U-233 to save lives.
To summarize, saving the U-233 saves money, lets us demonstrate LFTR's ability to burn thorium, and could save lives. Please appeal to your congressional leadership to save this precious resource.
Posted by Kirk Sorensen on 8/12/2009 But why save this particular 1000 kg of U-233? If we're going to start hundreds of LFTRs, there isn't enough U-233 to start all of them, and we'll have to use other sources of fissile material. So why worry about this batch of U-233?
Reason #1: Destroying the U-233 is a waste of money.
The Department of Energy is estimating that the cost of "downblending" U-233 with depleted uranium (predominantly U-238) followed by "disposal" at the Waste Isolation Pilot Plant (WIPP) in New Mexico will cost approximately $380 million dollars. This is the estimate as of December 2006, and it came from an article in the Knoxville News-Sentinel that is no longer available, but the text can be viewed on the thorium-forum. $380 million is a LOT of money, money that's being used to destroy U-233 rather than develop the LFTR technology that turns it into unlimited energy.
Reason #2: LFTR runs better when it is started with U-233 than any other fissile fuel.
The LiF-BeF2 dissolves uranium better than plutonium, and if you start LFTR on U-233 you start it the way that it will be running in the long run. It takes a lot of neutron absorptions for U-233 to turn into something other than uranium. You have absorb one (U-234), two (U-235), three (U-236), and finally four (U-237, decaying to Np-237) neutrons before you form your first transuranic nuclide. By contrast, if you were to start LFTR on highly-enriched uranium (which would be a very attractive way to dispose of HEU that was produced for nuclear weapons) you only have to absorb two neutrons to get to Np-237. Plus, HEU has a certain amount of U-238 in it, and U-238 is only one neutron absorption away from forming a transuranic isotope (Pu-239). Obviously starting on plutonium, you've already put a lot of transuranics in the reactor to begin with.
This may sound a bit confusing, so I've made an image to try to graphically depict what happens in the reactor when you start on different fuels. U-233 fissions more favorably, its products have more opportunities to fission, and it has further to go before it forms a transuranic.
Reason #3: U-233 allows us to prove "thorium burning" in a prototype reactor.
One of the basic underlying assumptions of the LFTR is that we can "burn" thorium, in other words, we produce enough U-233 to replace that consumed. By starting a prototype reactor on U-233, we can actually show this in a real-world case early on, rather than trying to extrapolate backwards from a HEU or plutonium startup. It is going to be important to demonstrate that LFTR can really burn thorium, and a U-233 start is the only conclusive way to demonstrate this.
Reason #4: The aged U-233 contains valuable decay products that could save lives.
The U-233 in the DOE's inventory has had 30+ years to decay. That means that some special isotopes like actinium-225 and bismuth-213 have had time to form in the stored U-233. These actinides, which can ONLY be formed through U-233 decay (not fission) have shown that they could be very promising isotopes for certain types of radiotherapies that could save thousands of lives every year. Even the Inspector General of the DOE has appealed to save the U-233 to save lives.
To summarize, saving the U-233 saves money, lets us demonstrate LFTR's ability to burn thorium, and could save lives. Please appeal to your congressional leadership to save this precious resource.
4 comments:
thanks Laura and thank Kirk Sorensen for allowing you to post his series of posts concerning this topic about Uranium, they are very good!
it's obvious that the government wants to destroy it so they get money from people paying for electricity. instead of going for the greater good their going for the cash.
Dear anonymous,
Did you know that none of the reactors in the US can burn U-233. Everything is set up to burn U-235 so that's going to be a lot of work and money to produce one. And, where would it be put? No one wants a reactor in their backyard.
To Anonymous 2
Uranium 233 is essential to starting and maintaining the thorium fuel cycle, as the articles I posted explain. At this time, at least three companies, notably Curt Sorensen's Flibe Energy, are working on developing the first commercial Liquid Fluoride Thorium reactors, which are based on the technology developed first by the late, great Alvin Weinberg, who developed the first civilian uranium reactors as head of Oak Ridge National Laboratory, but who was deposed by President Nixon, who wanted a nuclear technology that could help in building weapons. The thorium fuel cycle does not help with that, and so we are 40 years behind in developing this safe, economical technology.
The LFTR will be an extremely safe and economical reactor that produces almost no waste and is many degrees safer than even the excellent new AP-1000 uranium reactor. These reactors will be small, come with their own containment vessels, and can be transported on an extra wide truck after being assembled at a factory. The technology involved is a radical departure from that of the big 1 GwH uranium fission reactors with their massive containment vessels and intrinsic safety issues, that we have had until now.
But if we destroy the stockpile of precious U-233, we might never be able to develop this technology, which could make a universe of difference in not only the safety of nuclear and the cost of producing it, but whether we are even to have cheap electricity available to everyone in the future of energy scarcity and fossil fuel depletion.
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