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THORIUM. Is it really that safe and great alternative to Nuclear? Is it the Other Miracle that Bill Gates is looking for?

I've been against Nuclear all my thinking life.. so from about age 20 and am now 54. Japan has not helped me become a lover of Nuclear. One thing that I heard briefly in a news report, was the word Thorium. It is apparently a rare earth mineral that is found with Uranium and dug at the same time.
I read the following.. and are yet to check the facts...
* It is a very efficient source of power generating material.
* It has already been dug up and is sitting in piles
* If there is a problem, you just simply turn it off like a light
* The waste can not be used to make a bomb
* Current Nuclear plants can be converted to use it
* It's actually cheaper than Uranium
* It doesn't require those big exclusion zones

Personally, I don't know enough about it, but from what I've read in an article titled "A report on Thorium: The newest of the technology metals . by Jack Lifton" which certainly seemed comprehensive and informed, I'm starting to wonder why this conversation hasn't been had before.

Interestingly, I don't see any reference to Thorium on the Terrapower website even though Stewart Brand referenced it in his Debate FOR Nuclear Power at about the 7 minute mark in the debate. I do note that a search for Thorium on the Terrapower website gives no hits at all.. Refer 13:20 into the Bill Gates speech as well. Not sure why.

What do YOU think?

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    May 8 2011: This conversation took place since Kirk Sorensen spoke at Calgary's TEDxYYC, but before the TEDx Talk was available online. So as a follow-up, here's a 10 minute video on the subject of LFTR and Thorium! http://www.youtube.com/watch?v=N2vzotsvvkw
  • Mar 25 2011: Wayne, nuclear energy and nuclear weapons are different things. I do think that the media's focus on the nuclear problems in Japan is out of proportion to, say, the hte thousands of people who have already died and the thousands more will will likely die as a result of desdtroyed sanitation systems, lack of food, water, shelter, and everything that comes with not having sufficient electricty for long periods of time in a disaster area.

    But on to thorium. The thorium fuel cycle is very different than the uranium fuel cycle. The most promising design is the liquid fluroide thorium reactor, or LFTR for short. I highy recommend checking out http://www.energyfromthorium.com and http://www.thoriumenergyalliance.com The ins and outs of the technology are too involved to go into here. But I'll mention a few:
    LFTRs run at normal atmospheric pressure
    Passive safety systems ensure meltdown will not occur
    LFTRs can use our existing nuclear waste as fuel
    The waste produced by LFTRs are much less in volume and the worst of the radioactive elements present in the waste are harmful for about 300 years. We have technical and geological solutions to storing waste for this long (in vitrified glass, for example)
    Thorium is more plentiful than tin - there is no middle east of thorium.I share concerns about current gen II reactors and think the world's nuclear reactor's are outdated.

    Switching to a thorium fuel cycle or building gen III and gen IV uranium-fueled reactors are the way to go moving forward.

    Passive cooling systems would have been enough to stop the disaster in Japan. If a 40 year old, outdated reactor built to withstand an 8.2 can take a 9.0 earthquake and then only have it's backup cooling systems fail as a result of a 35 ft tsunami, I think that's a good sign of the safety of nuclear energy. So look up LFTRs and also the integral fast reactor (IFR), another nuclear fuel burning reactor that solves all the problems with traditional nuclear energy.
  • Jul 10 2011: Hi Peter, Thanks for your interest in finding out the truth about all this, which sentiment I share of course. However, I think there is a real world problem in making the LFTR message simpler. What's bad is that Thorium is an alternative fuel in a solid fuel reactor of the usual type; this is poles apart from the liquid fuel Molten Salt type of reactor that Kirk Sorensen is talking about, and that Wigener invented 50 years ago. In fact, if you happened to see NRC chief's rsponse to the (poorly phrased) question from one of his audience, it certainly appears that he did not appreciate this difference at all, and he is a Nobel prize winner. Or maybe he has became tactful and political.. By the way, Mr. Large possibly is on the same track: he speaks of processing and waste difficulties: with Thorium as a solid fuel;in a breeder process yes, but that is not at all what the LFTR is about. I have heard it said that one can complete a Phd program in nuclear engineering and never hear a word about LFTRs, but of course, plenty about the existing industries practices and ideas. Let's be clear on my possible lack of clarity: when I say breeder cycle, I just referring to the standard type of reactor that produces more fuel as a byproduct: apparently Thorium in LFTRs does that, but the fuel is used right there in its cycle; it is not extracted and stored or used elsewhere (as in bombs). This may be incorrect usage on my part; as I say, I was an engineer for years , but up to a couple of months ago I never even heard the term "Thorium Reactor". By the way, how can Thorium LFTRs be said "not to work" if one was in use producing energy for 5 years, with the information part of the history of Oak Ridge.? Maybe it was formerly "Top Secret" no doubt, but that was years ago. I understand that part of the airplane engine project also made some basic discoveries about how to make the process not only work, but work better. Apropos of corrosion problems, etc.
  • Jul 9 2011: Hi Craig. Reallly great to see so much interest in LFTRs. I am a retired engineer, but not nuclear. Haviing seen Kirk Sorensens videos, I am a little confused about "Breeder" reactors: are you saying that a LFTR is one because it produces the U233 it needs to continue the fission, once it has gone critical? By analogy to let's say, the infamous "Breeder Reactors " which could produce lots of bomb material. Mr. S. says the LFTR products cannot be used in bomb making, not because there aren't any, but because it is not a practical way to make a bomb.
    • Jul 9 2011: Hi Shawn, Craig and everyone who has contributed here. .. Thank you so much .. There are still little niggles created by John Large a Nuclear Engineer of Large and Associates,who says there are problems with the Processing cycle to split the fuel from the waste and difficulties actually storing the fuel.. He even commented that the Thorium Reactors don't really work.. He said the problems related to Thorium Rectors are insurmountable, in his opinion!! This was from a news report on Youtube http://www.youtube.com/watch?v=lOLo73k3OG0&NR=1&feature=fvwp at about the 2:20 point in the video...
      I guess the question that comes up for me is that is he a Nuclear Engineer and a consultant to the Nuclear industry or is he totally independent and unattached?
      Listening to that 10 second grab can certainly press the HOLD THE BUS nerve if someone doesn't take the time to learn what is really the truth.
      Might be time to simplify the message about LFTR to make it more easily communicated..
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        Jul 11 2011: John Large makes his living as a hired gun and has often been hired by Greenpeace.

        http://nucleargreen.blogspot.com/2010/11/john-large-greenpeace-hired-gun.html

        "Once again we note the hazard to media credibility that comes from automatically attributing expert status to the hired guns of partisan causes."

        IMO, for those that don't bother to read the link, John Large is a joke and every one of his comments is easy to prove wrong with a little research.
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      Jul 11 2011: Shawn, yes a LFTR is a breeder reactor, but it operates in the thermal part of the spectrum so it breeds slower and is more stable than fast plutonium breeders. In Kirk Sorensen's longer talks he covers this very well. He may have shown an illustration of it in his TEDx talk but can't remember.

      http://www.tpub.com/content/doe/h1019v1/css/h1019v1_138.htm
      http://en.wikipedia.org/wiki/Breeder_reactor#Types_of_breeder_reactors
      http://en.wikipedia.org/wiki/Breeder_reactor#The_thermal_breeder_reactor

      All commercial reactors breed fuel, but they have low (though still significant) breeding ratios.
      http://en.wikipedia.org/wiki/Breeder_reactor#Breeding_ratio

      By the way, there is nothing impractical about making a bomb from U-233 using modern robotic techniques. There are just easier routes to go if with current tech if you want to do it. Kirk's argument has nuances that are often lost in short heavily edited talks posted on youtube. Using thorium was the hardest path of the 3 choices they had on the Manhatten project to attempt to make a bomb so obviously they chose the other routes, the plutonium implosion device being the most stable if could be proved to work (Trinity). The point is that LFTR is a breeder reactor and could be designed to make plenty of U-233 for a bomb. This is why you want to design LFTR's technology with antiproliferation in mind, built into the design. It can be done. Making attempts for example to siphon off material for a bomb easily detectable (it would immediately cause the reactor to shutdown for example because one is operating in a correctly designed reactor just at criticality). One should also keep in mind that no civilian reactor of any kind has ever been used to make bombs. It's a very lousy way to go. Stealing the material from a civilian reactor is also a really lousy way to go.

      It's important to read this rebuttal to critics to understand the nuances,
      http://energyfromthorium.com/ieer-rebuttal/
  • May 17 2011: So far, I am flabbergasted that the MSR thorium reactor is NOT EVEN MENTIONED in the main stream media that I have seen, whereas "Nuclear Power Plants" (evidently of the Chernobyl and Fukushiima type) frequentlly are.
    What a devastating commentary on our Society!
  • Apr 19 2011: Peter I understand where you are coming from. I feel the same way. But I have been looking and I haven't found any negative information about LFTR's. So I have been wondering why they weren't built 40 years ago and why there still isn't a serious program in the USA to build a working commercialized prototype.

    Even if they did not produce any power if they can burn up and transmute existing nuclear waste into material that is safe in 300 years that would be worth it. But they also have the potential of producing power for less cost than coal. But I still have some unanswered questions.

    Are they a solution for the disposal of existing waste?

    What is the worst possible disaster that could happen at one of these reactors?

    Can they blow up?

    Can they be blown up?

    How safe would it be to live near one?

    They don't operate under pressure but they do produce significant quantities of poisonous radio-toxic gases. What kind of danger do these gases represent.
    • Apr 20 2011: As I understand it, LFTR was not pursued primarily because its waste products were poorly suited for the production of nuclear weapons, and the reason that they still aren't being built commercially in the US is because the established nuclear industry makes all of its money on uranium fuel production.
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    Mar 19 2011: I think Thorium is an excellent fuel but unlike what you heard that waste could be used to make bomb is not true. Waste could be used to refuel the reactor.

    Extensive research on this field have being going on in India.

    India has the world's second largest thorium reserves, and thorium can be used to build "breeder" reactors (which produce more fuel than they consume) and lead to self-sufficient power generation.

    I hope you found this useful!

    Good day!
    • Jul 9 2011: It's great that India is working on Thorium reactors, but its NOT great that they plan to use it in plants similiar to the existing LWR solid fulel types, which have all these problems that the LFTR doesn't. Really, India already is known toave nuclear bombs, they really don't need any more; and what other reason is there to build "breeder" reactors? "Producing more fuel than they burn" is really a Faustian bargain, and an unnecessary one: Thorium in the US is so cheap, it is considered a waste product..
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    Mar 16 2011: Just to make one thing clear at first:

    Thorium power is nuclear power.

    The main point of using thorium, in addition to the proliferation issues with uranium, is that there is 10 fold amount of it available compared to Uranium. If you take into account also the fact that we only use uranium-235 in our nuclear reactors, and this consitutes only 0.7% of the total amount of uranium, the increase is 100 fold.

    Thorium reactors also operate by burning uranium. This is created from thorium by bombarding it with neutrons. This forms uranium 232, which is highly radioactive and is hence hard to deal. This is why U232 can't be used for nuclear weapons, it's hard to handle.

    If you consider the events which are now unfolding in Japan, the heat being released at Fukushima is from the fission products. Fission products are an inevitable result of fission processes and therefore such an event could also happen to a thorium nuclear power plant.

    Thorium as a nuclear fuel is propably the way to go in the future. This is due to it's high availability and low price. But before we get there we need to learn a lot more about large breeder reactors and reactors operating on fast neutrons.
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      May 14 2011: No, the main point of Thorium is not it's greater abundance or where it's cheaper. IV generation uranium reactors would greatly extend the uranium resources making it last many many times longer than the current practices would allow.

      The main point of Thorium is that it is ideal for use in a liquid fuel reactors. Liquid fuel reactors have several huge advantages in terms of efficiency and safety. Efficiency because the you can easily burn the fuel to near 100% rather than only about 1% for one pass of Uranium solid fuel. Safety because the liquid salts are self-quenching, you heat them up they expand and you lose criticality necessary to maintain fission reaction, also you lose power and the solid frozen salt plug melts allowing the core to drain by gravity into a tank that maximizes passive heat dissipation. No need for diesel power generators to cool the core on shutdown means the problem that occurred in Japan would not have happened with thorium liquid fuel reactors. These liquid salt reactors operate at atmospheric pressure without high pressure water and can be gas cooled, Energy generation is more efficient gas turbines.

      So no, the events as happened in Japan with the melting of solid fuel would not have happened with liquid fuel. The explosive expansion of high pressure water into steam or the creation of Hydrogen gas from the zirconium cladding of the solid fuel would not have happened either.

      Thermal breeder reactors are much more inherently safe than fast breeders, and you can also build much small more compact reactors too. Bigger isn't necessary.
      • May 17 2011: I have been tryiing to locate some more specifics on MSR Thorium reactors. Thanks very much..Do I understand you correctly to say that such a reactor would be "failsafe" , or self-extinguishing (without positive human inputs) in the worst case scenario? If so, why aren't they all like that?! They might even be able to get Insurance...Rumor has it that the real reason is that the process doesn't produce weapons grade Uranium for bombs. What do you think of thiat idea?
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          Jul 7 2011: Yes,
          a well-designed Liquid Fluoride Thorium Reactor would shutdown on it's own with no humans if the power went out.

          If you tried to over-heat it you would just end expanding the liquid salt volume (the liquid is not pressurized and has a similar viscosity to water) & it there would be less fuel in the core of the reactor reducing fission causing the reactor to essentially shut off and start to cool.

          Nuclear engineers during World War II had three choices to make fission bombs. One through Uranium, one through Plutonium, and one through Thorium. Two of those three choices had more direct solutions. The last one through Thorium required too many steps and some big technical drawbacks. They chose to work with making Uranium (Little Boy) and Plutonium (Trinity and Fat Man) bombs. After the war, the experience with nuclear reactors used to make bomb material (Hanford) was used to make power plants for Navy ships and submarines. The first civilian reactors were basically Navy designs place on land. Only the nuclear plane idea being worked on at the Oak Ridge National Laboratory in the 50's and 60's and funded by the Air Force put such constraints on the designs (safety, compactness, no high pressure, no need for water, higher efficiency of fuel, no need to replace fuel because of Xenon desturction, etc.) that liquid reactors (molten salts) using Thorium which is usable in the thermal part of the spectrum became seen as a necessity. The lead scientist on the project was the same scientist who invented the light water reactors that the Navy was using. He though that use of liquids and thorium for civilian use was by far the better way. During the Nixon Administration, his voice become politically isolated. All the expertise in liquid reactors was at Oak Ridge NL where he was in charge. Other national labs and those in the administration favored solid fuel, fast breeder plutonium reactors. He was fired. Liquid reactor project lost it's funding.
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          Jul 7 2011: the irony. is that several years later, the Carter administration canned the Fast Breeder Plutonium reactor program. That ended the U.S.'s research into any kind of breeder reactor (plutonium faster breeder solid fuel reactors now used by the French, and the safer thorium thermal breeder liquid fuel reactors which are now gaining a new look in the last few years). Breeder reactors become synonymous in the U.S. with proliferation risks even though because people talked about faster plutonium breeder designs as if that was the only type of breeder. All institutional memory of the Thorium thermal breeder program was lost by late 70's and early 80's, and in the era before the Internet, the work became just books on the shelf in the library of the national labs. So much so that you could get a Ph.D. in Nuclear Engineering and NEVER learn about Thorium as a nuclear fuel.

          So problem is now while all the work was documented and because of the internet much of it is now online for people to discover, all the engineers and experts that worked on liquid reactors from the 50's through the early 70's in the U.S. are either dead or long retired.

          So in the information age. U.S. has no jump on anyone that decides to pick up the ball and run with it. Like for example China.
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    Mar 16 2011: Just this afternoon I stood outside the metro on the way home and began a discussion with two scholarly youths about a certain political foundation they are promoting, nuclear, thorium, what is happening in Japan etc...

    The whole of the conversation I found myself wondering if they found me as troubling as I found them. They were earnestly trying to convince me that the media coverage of Japan was being influenced by pressure from various diabolical Green organizations.
    Nuclear is completely safe as evidenced by the fact that no one has died in Japan. I guess Hiroshima doesn't count.
    There is in fact no need for the various redundant and in this case curiously ineffective safety systems.
    That teams of safety, rescue and health care professionals can afford to commit their time to involving themselves in assessing the fake and impossible threat of radiation poisoning.
    Persons who are anti Nuclear are caught up in a fear campaign to excite the ignorant public opinion and interfere with the progress of nuclear science...

    Is it just me who is a little worried here about what our education system is efficiently turning out.

    Its up to us to get our ignorant selves informed.
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      May 13 2011: No Hiroshima doesn't count as that was a bomb. That would be like equating a diesel generator to the Firebombing of Dresden. It's this kind of confusing nuclear weapons with nuclear energy that is exactly the problem. The fact that there has not been a new reactor built in over 30 years in the US has simply resulted in an industry dependent on running old reactors several generations behind current technology and incentive to develop better engineered systems. The whole industry in dependent on making a profit on the fuel production which itself is horribly inefficient (most of what is called waste is actually unused fuel that needs to be reprocessed). In Japan, you had 40+ year old reactors that had been scheduled to be decommissioned 7 years ago. The newer Tech survived the tsunami just fine and shutdown properly.

      I don't know about media coverage influence or political groups, but every large scale power system requires safety systems.

      People die installing solar or wind systems. A wind turbine blade value is pretty spectacular and dangerous.

      both sides need to be more informed.
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        Jul 22 2011: Once again I did not mean to trivialize the usefulness of this tech. I am sorry as once again my comparison drew away from my intended message. I just dont want the next generation to become as complacent in thier ignorance as we were about coal and oil... we all need to be aware and respect the fact that like a blade this tool can cut the hand that wields it. Nothing more.
    • Jul 9 2011: Wayne: Pardon me if I didn't underand your comment clearly: were you saying that the students were getting everything garbled up, or that you really were impressed that no one was killed by the reactors at Fukushima? The main point of all this is that ALL LWRs ()existng plants) CAN blow up, mellt down, and/or release incredibly toxic materials.. Yes, they do have an impressive safety record in comparison with coal mines, but iit is brought about by an ongoing, intensive, superivision program which requires outside energy as well as personel to keep going. The Thorium LFTR system, on ltlhe other hand, shuts itself down automativally without power intputs or intervention, in cases of trouble. To my mind, that is a game-changer. Anollther excellent point in favor of LFTRs is that they seem to solve complettely what to my mind was the ultimate objection to existing Nuclear LWR plants: they produce great quantities of super-toxic material that no one knows what to do with. (for the next 17,000 years or so), while the LFTRs can "burn" that stuff for fuel, and actually destroy it. Another game changer. You should look up Thorium-Kirk Sorensen" on Youtube for some fascinating videos aboout this.
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        Jul 22 2011: Yes I guess you can say the information was 'garbled up.'
        Your dialouge with Craige has been very infomative. Thank you Shawn.
        Please read my note to Craige above for more clarification.
  • Jul 12 2011: No problem at all Craig.. I took it as a positive...
  • Jul 12 2011: Thanks Craig.. checking out the link
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      Jul 12 2011: sorry, I was tired. I meant that comment about barely touching the subject to be directed to Shawn.
  • Jul 11 2011: hmm... so I get the feeling you don't have a vested interest in this, but are, like myself, searching for the facts and trying to get your head around why this isn't a major direction that governments aren't supporting.. I guess it's because they just don't know enough about it... time to raise the bar methinks....
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      Jul 11 2011: Russia has a program that may be further than anyone knows.

      France has a largely theoretical program that maybe finally be getting engineering experience it needs from the Czech Republic making it more of true European effort.

      South Africa is throwing their hat in the ring with a serious startup effort

      China maybe putting some big bucks into a LFTR project,

      and there are the guys in Huntsville plan to have a working commercial prototype in 5 years.

      remains to be seen who will be first
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      Jul 11 2011: Never underestimate technological and industrial inertia. LFTR while it seems a no-brainer still takes some serious money and engineering talent as well as consistent effort. You could say up until recently there hasn't been the consistent effort since the ORNL program was killed as it was about to take the next step during the Nixon Administration.

      just saw this, a nice essay on exactly this topic
      title: Fukushima: Nuclear power's VHS relic?
      http://www.bbc.co.uk/news/science-environment-14060913
  • Jul 6 2011: Fast Facts: What so great about a Thorium Reactor?
    •It’s safe: Nuclear reactors, like the one at Fukushima need constant cooling – even if they’ve been switched off. Nuclear ‘meltdown’ happens when these cooling systems fail (like in Fukushima) and the uranium fuel core overheats. But within a thorium reactor, a ‘meltdown’ simply isn’t possible – turn the power supply off and the reaction just stops.
    •It’s cheap: At the moment, thorium is being thrown away. In rare earth metal mines around the world, millions of tonnes of thorium are extracted. They don’t need it – and so these companies are literally paying someone to get rid of it!
    •It’s efficient: Thorium reactors (also called LFTRs) use liquid fuel rather than solid uranium. Liquid fuel means things can mix together better, meaning thorium reactors are 200-300 times more efficient than even the best uranium reactor. Powering 1,000,000 homes for one year needs only one ton of thorium! (compared to 250 tons of uranium)
    •It’s clean: Thorium ‘burns’ much more cleanly than uranium, and only produces 1% of the waste (see image below). Much of the ‘waste’ from a Thorium reactor is actually quite useful and can be re-used for powering space probes (amongst other things)!
    •Reactors are easy to build: Conventional nuclear power plants take about 15 years to set up and build. A thorium reactor is a much more simple structure and operates at a much lower temperature., therefore they can be much smaller and are faster to build.
    Advantages of Thorium 233 over Uranium 235
    1. Waste products can contain significantly less long-lived radioactive waste than uranium or plutonium.
    2. Weapons cannot be proliferated from Thorium.
    3. Thorium is more energy efficient, operating at higher temperatures.
    4. There are massive supplies of Thorium worldwide.
    5. Less environmental damage to the environment through mining, extraction, and processing.
    6. Less damaging health effects to workers during extraction.
    7. Thorium does not require enrichment.
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      Jul 22 2011: Wow.
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        Jul 22 2011: your response got me to look at Tushar's response and in the interest of get the story straigh, there is a mistake in his post

        This is not correct.
        "A thorium reactor is a much more simple structure and operates at a much lower temperature... "

        Thorium fluid reactor, LFTR, or any molten salt reactor actually operates at a higher temperature than a conventional solid fuel reactor. That's one of it's advantages. Running at a higher temperature means it can use the more efficient gas turbines (Brayton cycle) rather than the less efficient fluid/steam turbines (Rankine cycle) found in conventional pressurized water reactors. The narrow range for water as a fluid is why conventional reactors run at high pressures, so that the temperature range can be increased to increase efficiency by running the reactor at higher temperature. But there are limits to this and it creates safety issues from both the high pressure and the presence of water. Water under such high pressure is the reason that containment vessels are so large because a loss of pressure would result in instant explosive conversion of water to a gas. A thorium fluid reactor like LFTR runs at higher temperature and the salt remains a fluid over a much larger range including the working temperatures so there is no need to pressurize. And this means your containment structure needs to be only slightly bigger than the reactor vessel. Far simpler for safety but the plumbing is very challenging requiring very smart careful engineering for the two fluid systems that would be the best.
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    May 14 2011: Yes, "Current Nuclear plants can be converted to use it" BUT, you give up a LOT of the advantages of thorium by using it in solid fuel form. It's the reason the current nuclear industry is negative on Thorium. They only know the solid fuel engineering and from a solid fuel perspective thorium isn't that good.

    India is trying to go the solid fuel thorium route, I feel it's a big mistake. Given their greater abundance of thorium resource rather than uranium you can see why thorium is attractive to them. It's just unfortunate that they are going with the familiar solid fuel route. Lots of issues with that.

    China now appears to be pushing to using thorium the smart way in new fluid fuel reactors (molten salt reactors).
  • Mar 16 2011: OK.. thanks Wayne and Jouko.
    If that is what education institutions are putting in our kids heads, then I also have concerns Wayne. I look at the comment that was thrown out there almost off the cuff that if this was a Thorium Reactor, then you would just turn it off.. From what Jouko has just educated me on, I see I was completely mis-informed... good thing I have an enquiring mind and clever people in my life.. well at the end of a keYboARD.. and an 18month old grandson pressing caps lock with his toes..
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      May 14 2011: Jouko misinformed you so the kids are alright after all LOL

      Turn off the power on Thorium Liquid Fuel Reactor and it shuts itself off with any human intervention. It's what they did weekly for 5 years with the test reactor in the 1960's. On Friday, they would shutoff the power and go home for the weekend and come back on Monday and turn it back on by heating up the salts and pumping the back into the reactor core.

      The problem with solid Uranium fuel is that it is a ceramic and has very poor heat dissipation properties. Got to be constantly pumping water to get that heat out.
    • Jul 9 2011: This whole topic is quite tricky. We "onverts"think that LFTRs are the greatest, but let's be aware that when some , even knowledgable,people talk about "Thorium Reactors" , they may very well be thinking of the solid furel, "fast breeder" reactors, simply using Thorium instead of Uranium; this is not much of an improvement over the Fukushima type, as far as saftety goes. It's good if you want to make bombs, I suppose. I heard a talk by Nobel prize winner head of the NRC who seemed to be thinking this way, I understand it is possible to get a degree in Nuclear Engineering and not even hear a word about LFTR. i am a retired engineer, civil , but I must say I never heard a word about it before a couple of months ago. It looks like it was all (internal) politics in the atomic bomb program of years ago, and of course was "Top Secret". Now there is the promblem that the large nuclear power industry "business model" completely depends on keeping soliid Uranium fuel rods as the standard fuel. Thorium is so cheap in the US , it'sthe status of a waste product (I mean the ore residue from "Rare Earth" production; its not radioactive particularly.)
      t
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        Jul 11 2011: @Shawn, Excuse me for saying this as a physicist, but you need to do a lot more reading. All the comments you have made here seem to be just as someone who has barely touched the subject.

        Also, a Nobel prize is nothing more than a recognition of an achievement in your area of expertise. It doesn't necessarily make you any smarter or more knowledgeable than any other scientist outside their area of expertise. Just as a black belt in Judo may not be much more knowledgeable about karate than a white belt in karate, and likely to make white belt mistakes, head of the NRC which is head of an organization that spends all it's time thinking about solid fuel uranium pressurized water reactors and that has never studied in real depth liquid reactors would also be unlikely to get the facts straight on LFTR.

        LFTR doesn't need converts, it needs people willing to look at it with an open mind because like any dense energy system there are risks. It's just happens to be a system where engineering safety doesn't have to fight the physics making it very attractive when compared to current LWR designs.
        • Jul 12 2011: You're absolutely correct.. I HAVE barely touched the subject. I am not an engineer or a physicist, and come from a place of totally ignorance, hence me query out to the world to find people like yourself and Shawn who will know more than me so I can learn the TRUE facts rather than just what I can find on the web.
          Thank you very much for being a large part of my learning. I'm off to those links you suggested and more research.
        • Jul 12 2011: Craig: You are certainly right that I have just touched the subject; I thought I sort of explained that myself. Did you mean to say that what I said was incorrect? And about Nobel prize winners was, I thought , almost exactly what you said as well: he's very capable, no doubt, but perhaps overspecialized. As to engineering safety, is it not correct to say thlat LFTRs are potentially "failsafe " in the sense that no outside actions or powered devices are required for an automatic shudown? I am of course, just repeating what some actual nuclear engineer said; is it not correct? I do not consider the usual run of industrial accidents as in the same risk class as a "critical " meltdown like at Fukushima. As to my admitted lack of qualifications: since we all are going to suffer the consequences of nuclear accidents, we are naturally curious about the whole thing. It's sort of like being a passenger on the Titianic. But any clarifications you can provide would be most welcome. Incidentally, I think LFTRs really DO need converts; even the technical people I've discussed it with are all too quick to say "Oh, it's been tried, and found wanting, otherwise we'd have it now.