Blue Ribbon Commission learns about thorium

On August 30 Robert Hargraves presented a ten-minute version of Aim High to the Reactor and Fuel Cycle Subcommittee of the President’s Blue Ribbon Commission on America’s Nuclear Future. All the presentations are posted here by the commission.

The commission will not recommend any specific technology such as LFTR, but this presentation might nudge them closer to recommending policy changes for NRC that would facilitate SMR (small and medium reactor) licensing, and also support technology neutral licensing, so that technologies differing from today’s standard light water reactors might be approved.

Here is the text of the presentation, one paragraph per slide.

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19 Replies to "Blue Ribbon Commission learns about thorium"

  • donb
    September 8, 2010 (9:56 am)
    Reply

    The NRC favors light water reactor technology only by default. The LWR is the only thing they know. The unfortunate truth is that the regulators there will need to be educated (add approval time) about other technologies, at the expense (add money) of those who propose those technologies.

    It will take a combination of industry pressure, government direction (from outside the NRC), and government funding to get the NRC out of its LWR comfort zone.

    I hate to say we need more government funding for something, but our energy needs are too important to just "kick the can down the road" until we face a crisis. But since government has set itself up as one of the major roadblocks to the development of advanced nuclear energy sources, it needs to share the pain that these roadblocks cause by providing appropriate funding.

  • seth
    September 8, 2010 (11:27 am)
    Reply

    Much to little. The DMSR should be emphasized. We could be mass producing these little suckers in 5 years after a relatively minor amount of development work.

  • Jim Van Zandt
    September 8, 2010 (11:52 am)
    Reply

    A few nits:

    "Cut…to zero by 2058". Please delete "to zero". There will still be lots of CO2 emissions, and you shouldn't imply otherwise.

    "Check growth" should be "Check population growth".

    "Avoid weapons proliferation" should be "Avoid nuclear weapons proliferation". Sadly, there doesn't seem to be a hope of limiting conventional weapons.

    "Consume world fissile stocks" needs rewording. One of the problems with light water reactors is that they are consuming the only stock of fissile material we have inherited, which is U235. We need to consume more of the fertile material, and less of the fissile. Maybe just "Reduce/consume radiotoxic waste".

  • Robert Hargraves
    September 8, 2010 (1:31 pm)
    Reply

    Jim, thank you for your suggestions. I'll try to clarify future presentations. I don't mean to mislead, but to keep the number of words on the screen to an absolute minimum

    The "cut to zero by 2058" applies to the coal CO2 emissions described earlier in the presentation."

    I didn't use the wording "nuclear weapons" because I was trying to reserve a warm and fuzzy reception for the word "nuclear" in "nuclear power". Maybe futile. Maybe we should revive "atomic energy".

    Regarding consuming fissile stocks, plutonium can also be used as a startup fissile material, perhaps with some preprocessing (a chloride reactor converting plutonium/thorium to U-233). The benefit is that the world might want to reduce of weapons-capable fissile materials, including the U-235 that is produced in enrichment plants.

  • Rod Adams
    September 9, 2010 (7:48 am)
    Reply

    @Robert – I am with Jim on this issue. Though a majority of people – who often do not understand the technology – may think that fissile materials are bad, the technical reality is that they are simply materials that are more readily converted into useful energy than fertile materials.

    I call them the "kindling" or "seed corn" of nuclear fission. If they are not actually formed into a weapon, they are not particularly dangerous and certainly are not something that this generation should actively destroy. That would not be fair to future generations that might want to start up a few thousand new reactors every year.

  • Kaj Luukko
    September 10, 2010 (4:48 pm)
    Reply

    How much fissile material is needed for the initial load of one LFTR?

  • Robert Hargraves
    September 10, 2010 (9:02 pm)
    Reply

    The initial fissile load might be 100 kg of U-233 for a 100 MWe power LFTR. It would consume about 100 kg of thorium annually thereafter.

  • David Archibald
    September 12, 2010 (5:27 am)
    Reply

    As the U235 startup material would have some U238 associated with it, does that mean that some plutonium would be produced in the inner core? If so, what is the fate of this material or would it get consumed about as quickly as it is formed?

  • Robert Hargraves
    September 12, 2010 (6:46 am)
    Reply

    If started with LEU U-235 rather than U-233, the U-238 would absorb neutrons to make Pu-239, which would fission, or form Pu-240, etc. About 1/3 of the energy at the end of a fuel cycle in a standard LWR plant comes from plutonium fission. After some years to reach equilibrium, the U-238 and plutonium and higher actinides would decrease, owing to the long path of neutron absorptions to change from Th-232 to Pu-239. In the DMSR version of LFTR LEU is continually added so the plutonium content remains higher, but the mix of inseparable other plutonium isotopes makes the material useless for weapons.

  • David Archibald
    September 16, 2010 (4:29 am)
    Reply

    Robert, thanks for that. Regard the U235 concentration, is there an optimal level for the starter material? Would 50% U235 and 50% U238 work, for example? Could one throw in the pellets out of spent fuel rods and start them up on 1.5% U235, 1.5% Pu and 97% U238? Please forgive if these are very stupid questions.

  • Robert Hargraves
    September 16, 2010 (6:04 am)
    Reply

    50/50 U-235/U-238 would work, but transport of HEU (>20% U-235) to commercial reactors is virtually forbidden, for fear the material might be hijacked for nuclear weapons. We could not simply throw in the pellets of spent fuel; some preprocessing would be required, for example to remove the fission products.

  • David Archibald
    September 18, 2010 (7:08 am)
    Reply

    Another question if I might. I am giving a presentation on energy security at a think tank event in Washington in early November. I have quite a few slides in on thorium, which I have picked up from other presentations. I would like to get internal consistency amongst the slides I am using. One slide says that 1 GW produced from thorium will produce 0.5 kg of plutonium and 0.3 grams of Am and Cm. Another slide ways that 1 GW produced from thorium will produce 30 grams of plutonium. Which figure is correct, and if neither, what is the correct figure?

  • Robert Hargraves
    September 18, 2010 (7:31 am)
    Reply

    Dave, there are two meanings for "produce plutonium". One is to produce it in the output streams from LFTR, and another is to produce and maintain it internally in the reactor fuel core. There would be no plutonium in the waste stream of fission products if the chemical separation for removing waste products were perfect. The IFR project folks were projecting about 1% leakage into the waste. The plutonium in the reactor builds up slowly, is fissioned or transmuted to a higher atomic number nucleus, and reaches some sort of equilibrium after many years. Dave LeBlanc says it is higher than 0.5 kg.

  • David Archibald
    September 18, 2010 (10:57 pm)
    Reply

    Thankyou. So, if the core at equilibrium held 0.5 kg of plutonium, a single reprocessing at 1% leakage would produce 5 grams going off with the fission products. To get 30 grams of plutonium per annum, the core fluid from a 1 GW reactor would be reprocessed six times a year.

  • David Archibald
    September 27, 2010 (7:36 am)
    Reply

    Further on the presentation I will give, can anyone point me to a piece saying why thorium fast breeder is a whole lot better than uranium fast breeder? Starting with why uranium fast breeder has to be in the fast spectrum, which in turn dictates the size of the reactor blanket? And why it has to have a sodium coolant and that in turn dictates size considerations. If size is an issue, is the BN 600 a minimum size for this technology perhaps?

  • Robert Hargraves
    September 27, 2010 (10:23 am)
    Reply

    Dave, for some preliminary insight download the presentation and look at the very last slide, which was prepared for questions that were not asked. Kirk Sorensen prepared this. It shows absorption and fission cross sections for thermal and fast neutrons.

  • Jim Lynch
    December 3, 2010 (1:29 pm)
    Reply

    I do not have the educational background to understand half of Dr Robt Hargrave presentaion "Aim High" is all about, But I do hope that His suggesting of building a smaller Unit might be feasible & could start almost Immediately. Look at the Conditions in Haiti whereless less than 12.5% of the population have access to electricity. With Their recent Election Rusults exspected to 12/7/10 Get a conmittmrnt from New government there that they would allow a private Joint venture to develope a Thorium Powered Utility. Contact Every Non-governmental owned utility in the world for a pledge of funds to get the project moving, Offer them in exchange Units of Ownership in the venture as well as Lets say 50% Interest in all patents developed as a result of the implementation of the venture. It is obvious that the naysayers have to big a voice with US Gov't in developing an energy policy and research budget that is adequate to meet the cost outlined by DR Hargrave.

  • Roy Harvie
    January 16, 2011 (9:50 pm)
    Reply

    So does anyone know if the Blue Ribbon Commission paid any attention to Dr. Hargrave's presentation? Have they made any statement on the LFTR?

  • Robert Hargraves and
    January 17, 2011 (5:33 am)
    Reply

    I now understand that the Blue Ribbon Commission will not endorse any specific technology, but will recommend new policies. I'd guess they would be about NRC fees and procedures for SMR licensing, and about responsibility for spent fuel disposition.


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