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  1. While I am convinced that MSR technology and thorium fuel is the long-term future of nuclear energy, I am also convinced that for the present the best designs available are Gen III and Gen III+, and these are the ones that we should press forward with. Supporters of more esoteric designs of nuclear reactor, tend to let their enthusiasm blind them to the fact that there is a lot of development left to do from where we are today, and those of us that have been involved with launching radical new technology in other domains know that there is a hard road ahead, and many potential pitfalls where things can go wrong (and will) before MSRs and thorium fuels can be considered commercial options. Furthermore there will be little interest in funding these things at the moment, and regulatory approval is by no means a given.

    1. @DV82XL and SteveK9, while the Chinese may be ‘pressing forward’ with Gen III+ designs, they are also pressing forward with building power plants based on current generation reactors. Indeed, the Chinese are doing what the United States should be doing but to a great extent is not. Our need for clean, affordable energy is great. We have relatively cheap natural gas right now, with even more natural gas powered generation coming. I smell a spike in natural gas prices sooner than later. Only at that point will building more light water reactors and developing advanced reactors start looking cheap. Perhaps then we will close the barn door, but the horse will be long gone, and slow in returning. At that point, many in government will be looking from someone to blame (other than themselves), while public outcry increases.

      1. @donb – High natural gas prices – even for a relatively brief period of time – lead to higher profits for natural gas producers and higher bonuses for the management and executives at natural gas companies. Those entities have a overweighted influence on public policy as determined by officials who have been elected in a system where people who contribute money have louder voices and more electoral influence than people who do not contribute money.
        As I mentioned in a recent post, the methane extractors – aka the oil and gas companies – have figured out that every reactor-year of delay that they can put into the nuclear renaissance is worth at least $365 million. They have a large incentive for selling the idea that gas is cheap now and will be for the foreseeable future. They will also lay the blame on as many outside influences as possible once the prices begin their inevitable climb as the immutable laws of supply and demand work their predictable magic.
        As electric power producers continue betting on being able to take more and more gas, the price of gas will rise as surely as the sun rises each day. This is “deja vu all over again” for those who paid attention during the dash to gas in the 1990s through early 2000s. I am long on gas producers and adding more to my portfolio as the story unfolds.

  2. I agree with DV82XL. I’ve noticed that the loudest voices tend to be from those who have the least amount of real experience working on developing conceptual designs for new nuclear reactors. Such work can be quite sobering. The real engineering challenges are not obvious from a thirty-second or even hour-long description of the design.

  3. The Chinese are ‘pressing forward’ with Gen III+ designs. It also would not surprise me if they are the first to develop a working TMSR design. The idea that a nation with the resources of the United States could not do both is wrong I think. After all, we are about to spend another $800 Billion this year on ‘defense’ (against what you might ask). What is lacking is the will. Nobody’s big bonus depends on working on a new reactor design.

    1. Seems like the LFTR would be a good design for load following, just a matter of removing the heat. I think the original concept was for powering aircraft–push in the throttle, allow more air to flow and take away the heat and you get more power. The time rate of change (dP/dt) for the grid is probably low enough for a LFTR to follow provided it wasn’t already at 100%.

    2. EL – I would like to try to respond to some of your somewhat more technical questions that Kirk Sorensen did not have a chance to cover (Kirk focused on answering the questions posed him by Dr. Kiki and the online folks on her support chatroom).
      It is perceived in some quarters, including the Secretary’s Office at DOE, that Generation-4 Thorium Molten Salt Reactors suffer from corrosion problems that keep this promising and economical reactor design from being viable.
      To those who harbor these fears I would like to suggest the following two ORNL reports which were prepared by the staff at ORNL in response to the operational experience of the ORNL MSRE experiment from 1965-1969.
      H. E. McCoy, Jr.
      ORNL/TM-6415 (1979): Development Status and Potential Program for Development of Proliferation-Resistant Molten-Salt Reactors
      The strategy outlined in these reports from ORNL suggest that corrosion in a Thorium Molten Salt Reactor could be well controlled through the following two part approach:
      1) add 1% to 2% Nb to the Hastelloy-N to reduce grain boundary embrittlement and tellurium attack at elevated temperatures by exposure to thermal neutrons
      2) intergranular attack and cracking on Hastelloy-N is greatly reduced when the fuel-salt oxidation potential, as measured by the ratio of U4+ to U3+, is less than 60. Monitoring and careful control of the oxidation state of the Fuel salt can be used to reduce corrosion on Hastelloy-N to levels permitting extended lifetimes in excess of 30+ years in a MSR. A simple, closed loop, microprocessor controlled instrument can be added to the reactor that will periodically monitor and control fuel salt redox state and add small pellets of Beryllium, when required, to keep corrosion under good control.
      The International GIF Gen-4 MSR program has made steady progress on MSR materials and corrosion issues. Russian researcher Dr. Victor Ignatiev has done long term corrosion studies on Hastelloy-N derivative alloys exhibiting exceptional resistance to tellurium attack and intergranular cracking. Ignatiev has been performing longer term corrosion testing (10,000 hours at high temperature) in molten salt loops to insure materials and corrosion issues are at a point that practical MSR (LFTR) reactors can be built safely.

      1. Bob – good info. However, it is worth putting the “long term” corrosion studies into perspective – 10,000 hours is just slightly longer than one year, which is 8760 hours. There are proposed solutions, but the accumulated knowledge associated with MSRs is minuscule compared to that associated with light water. The MSR advocates would be well advised to make sure they are not guilty of comparing ideal systems that have not yet been developed to the LWR technology that was developed in 1950. LWR designers and operators have either solved or mitigated a lot of challenges during their 50 years of continuous and extensive operations.

        1. Rod – Your points are well taken and there is no denying that there is vastly more operational experience with LWRs.
          My point would be that significant operational experience exists with LFTR in the 4 year long MSRE experiment and the operational experience of that research reactor which was very positive – no emergency scrams or shutdowns in four years – for the last two years of operation, when the reactor happened to be running with U-233 in pure Thorium Fuel Cycle, the reactor was routinely shut down within about 1/2 an hour every Friday evening, fuel salt and fuel drained out into a preprepared drain tray that changed the salt geometry such that it stopped fission generation of heat through the weekend, and then was started up each Monday in a half hour to 45 minute process when the cold salt in the drain tray was heated with external heaters and pumped back into the reactor to start another week of operation. This style of routine operation was adopted because none of the ORNL operators wanted to give up their weekends and time with their family to sit with the reactor. Very routine and uneventful startup and shutdown of the reactor occurred each week for over two years with no adverse experiences.
          I believe that there are currently no defensible reservations or doubts on the adequacy of LFTR reactor materials right now (and this information and proof should be fed back to Dr. Chu and Dr. Holdren to transmit to decision makers in Washington) that would prevent building LFTR prototypes. Good solutions have been devised and experimental verifications, and the building of prototypes should proceed. LWRs are much further down the learning curve and that is certainly a good thing, but innovation is the future of every industry and harnessing the power from Thorium fuel synergized by molten salt technology would help preserve American leadership and quality of life and change the economics of nuclear production of electricity while also improving the already excellent record of safety.
          I would concede that longer corrosion tests out beyond 10,000 hours to perhaps 100,000 hours would be desirable. Performing corrosion tests at higher than anticipated operational temperatures allows accelerated verification of the corrosion resistance of improved Niobium enhanced versions of Hastelloy-N as critical corrosion processes are increased with temperature. Solubility of the most reactive component in the Hastelloy (chromium) in the Hastelloy depends strongly on temperature, so testing corrosion at higher temperatures permits an effective accelerated test. At the ORNL design specification of 704 degrees C for the operation of LFTR we have good and dependable solutions to prevent tellurium attack on the granular boundaries of modified Hastelloy-N and this information deserves to be fed back to the decision-makers in Washington. For the purposes of efficiency, it would be desirable to operate LFTR at even higher temperatures around 800 degrees C to permit total system energy conversion efficiencies (thermal energy into electric energy) approaching 50% to be achieved. I would suggest building the first modern generation LFTRs at the ORNL design specification of 704 degrees C where I think clear defensible solutions to all materials problems exist and make operation at higher temperature (800 degrees C and above) a second phase of enhancement.

          1. LFTRs can also be subject to graphite swelling problems as a result of heat and damage from intense thermal neutron fluence. DOE INL is currently certifying new grades of nuclear graphite as part of the PB-AHTR program that should be less subject to this problem, but I think it is prudent to build the first modern prototype LFTRs in a fashion that easy, quick, and routine replacement of the reactor core and its graphite can be made say every ~3 years. While some suggest that we have not proven that 30 year operation of LFTRs (materials and graphite) is proven beyond all possible doubt, I believe that ORNL and recent GIF GEN-4 MSR (Ignatiev) studies show that good solutions exist. If there are still doubters I would suggest that if you will not yet concede that good 30 year lifetime LFTR materials solutions exist, would you consider a solution that would involve low cost routine core and graphite replacement every ~ 3 years while operating the LFTR at the ORNL design temperature (704 degree C). The concept would be a replaceable core unit shaped a bit like an oversize (but still small) automotive can style oil filter that has attachment channels on both top and bottom ends. This inexpensive, premanufactured assembly made of modified Hatelloy-N using improved low swelling nuclear graphite could be swapped out quickly and safely as a replaceable unit and replaced with another replaceable core unit. This would be a routine relatively minor interruption in service that could be accomplished in less than two days and be similar in impact to the periodic fuel reloading interruptions that are required of conventional commercial LWRs. Czech Researchers have shown that much higher performance and efficiency as a thermal fuel breeder (doubling time of rare U-233 fuel in less than 3 years) can be achieved by driving the LFTR cores hard while subjecting the Hastelloy cores and nuclear graphite to high thermal neutron fluence that would preclude 30 years of operation. Small replaceable LFTR cores designed for easy replacement would be a low technical risk and high performance path for the first prototype modern commercial LFTRs.
            In a vein similar to the popular misconception regarding conventional nuclear frequently echoed by even Presidents elect

          2. @Robert – it is not hard to turn startup and shutdown into routine operations for a variety of reactor plant designs. I would bet that I have more of each of those under my belt than any commercial plant operator who was not in the Navy and I only went to sea for about 6 years.
            The AVR in Germany also had a rather interesting way of shutting down for the weekend and in the evenings. The operators simply turned off the circulators. The core heated up enough to shut down due to the negative temperature coefficient of reactivity. When they wanted to start up again, the operators turned on the circulators.
            My point is that thorium and MSRs are interesting, but not a quantum leap compared to other fission power systems. They are a quantum leap when compared to combustion power systems. Those are the real competition and those are the sources that should be the target of the well organized evangelism campaign.

            1. Rod – Thorium advocates are nuclear advocates first. There is not much advantage in offering inadvertent “helps” to the nuclear opposition.
              When your favorite technology (Thorium LFTR) has sat on the sidelines for four long decades without good engineering justification it is just a little hard to wait.
              (I apologize for inadvertently deleting one of your thoughtful and very fine comments – sorry . . . I am still learning how some of the Blog mechanics work and I made a mistake).

              1. @Bob – take a good look at the comment that you made and tell me that such information would not be used as fodder by antinuclear activists.
                I understand the frustration of sitting on the sidelines, but the people keeping you out of the game are not the LWR builders – they are the fossil fuel pushers.

                1. Rod, I would disagree here. What Robert wrote should be used by nuclear advocates as a demonstration that we do have feasible ways to solve the issues which they themselves think need to be solved before we push with PWRs. I agree that here and now all we have is GenIII/+ designs, but their advocates should use the LFTR argument to keep any opposition at bay. And yeah,funding of a research prototype of a MSR/AHTR would be nice too 🙂

                  1. The problem here is that using that line of reasoning, validates those issues, all of which are false. Furthermore, the antis are not interested in solutions and will just move the goalposts, as they have in the past.

                    1. @DV82XL – absolutely. Remember, folks, many of the people who actively support the antinuclear movement through donations and political clout hate the idea of any energy source that is more capable than fossil fuels. Some of you cling to the myth that the underlying reason for that position is a hatred of humans and their desires for abundant living. I remain convinced that the underlying reason for disliking any energy sources that is more capable than fossil fuels is because that implies that the petroleum era is ending with a loss of markets, income, wealth and power for fossil fuel pushers.
                      As Sheikh Zaki Yemani reminded his fellow OPEC members many years ago (during the Arab Oil Embargo of 1973), “The Stone Age did not end for lack of stones and the Oil Age will end long before the world runs out of oil.”
                      Most of the observers who have discussed the meaning of that quote have ignored the real source of his concern. Yemani, like the Saudi kings that he advised, knew enough about atomic fission to be very concerned about its implications for his country’s only real product worth trading in a world market. In the case of the October 23, 2003 article linked above, the author was sure that the hydrogen fuel cell was going to be what broke petroleum’s chokehold on the world’s economy.
                      So why is Sheikh Yamani predicting the end of the Oil Age? Because he believes that something fundamental has shifted since that first oil shock

                2. Rod – I agree that my post could potentially provide help and solace to the anti-nukes (and I happily will try to remove it).
                  In its place I would say that Thorium LFTR has the potential to improve the economics of nuclear power generation while not sacrificing safety and that of the two natural nuclear fuels. U-235 and Thorium-232, only thorium can be completely consumed in a “thermal-spectrum” reactor. To completely consume Uranium-235/U-238 requires a “fast” neutron spectrum reactor. All of our reactors today are “thermal-spectrum” reactors, and they

                  1. @Robert – Th-232 is only fuel in the presence of either U-233, U-235, or Pu-239. It cannot sustain a chain reaction without help from those fissile isotopes.

                    1. Rod – You are certainly correct that Th-232 is a fertile fuel (and requires exposure to thermal or fast neutrons to convert it into U-233 fissile). Th-232 is the true fuel of a Thorium LFTR fitted with a Th-232 breeding blanket (LFTR folks would call this a 2-region/ 2-fluid LFTR). Aside from the original startup charge (that must be fissile – ideally U-232 but U-235 also works well – Pu-239 is harder to keep dissolved in the typical fluoride salts used in adequate concentration to sustain fission – but even Pu-239 is practical with a little tuning of the salt and the reactor).
                      What might not be widely recognized is that, once the startup charge of fissile (U-233) is provided for, the true fuel of a Thorium LFTR with breeding blanket (2 region/2-fluid LFTR) is just Thorium. As the LFTR operates it makes the U-233 it needs by transmuting the Thorium in the blanket. As long as you continue to feed Thorium into the blanket, the LFTR will continue to run for potentially hundreds of years while internally producing all the fissile U-233 fuel it needs to operate. Once started a 2-region/2-fluid Thorium LFTR requires no more fissile fuel for after startup the true fuel of a LFTR is only Thorium.

  4. I thought Dr. Kiki was pretty.
    I thought Kirk was in particularly fine form. Kirk is a natural teacher.
    LFTR is one of the most manufacturable types of new reactors (does not require the forged ~600 ton reactor containment vessel that LWRs require to be safe) and could be expeditiously mass produced to replace the electricity produced from burning coal.

  5. @Robert – pretend I am from Missouri. Show me a LFTR that does all of the remarkable things that you claim. Show me a LFTR that has actually produced reliable electricity for a sustained period of time. Show me a path towards licensing the fuel cycle technology required in something less than a decade here in the United States.
    Again, your comments about LWRs are limited. We have been building LWRs in the United States with US manufactured components for the past 60 years. Not all of them produce electricity. Not all of them are so large that they require 600 ton forgings. The fuel required to keep them running is being mined, processed, fabricated, and delivered to commercial plants for a total cost of 57 cents per million BTU and that number includes an allowance for the cost of storing the used material until such time as we decide that it is worthwhile to put it to use. At least 4,000-5,000 people per year complete light water reactor focused training and education programs and that has been going on for at least 4 decades.
    The “waste issue” is not an issue on any objective measure. It is only a cooked up issue by opponents who do not understand that the only reason it is an issue for the industry is that it represents a non performance of a contracted service.
    If I thought that pursuing a different technology would silence nuclear energy critics, I might be more enthusiastic. LFTR evangelists seem to think they have answered all of the questions about nuclear because the answers are different from those that LWR or fast reactor supporters offer. I understand that belief – I held it myself for about a decade as I pushed for pebble bed reactors using low pressure N2 gas as the coolant. Nearly every one of the advantages you mention for LFTR also apply to the Adams Engine, but I think my concept answers a few more of the final use questions because it is designed from the ground up to avoid the use of a steam plant secondary. LFTR temperatures are not high enough to effectively use Brayton cycle heat engines without a lot of tweaking and reheat efforts.
    However, no matter how good your system is at answering technical challenges, the opposition will never go away and will never get any less strident or less well organized. It will certainly never become less well funded or politically connected. LFTR poses the same existential threat to the people whose wealth and power comes from “petrodollars” as all other fission technologies do.
    We will only succeed by recognizing the truth and by helping others to understand that the challenges facing any form of fission are minor compared to the impossibility of capturing emissions from combustion and especially the impossibility of having a sustainable, prosperous society for all by continuing to depend mainly on burning fuel that took hundreds of millions of years to manufacture at a rate of several million years worth of production every year.
    Please stop comparing LFTR to uranium fueled thermal or fast reactors. Stop attempting to blow up solvable or solved technical issues into something that the nuclear opposition can use. Coming from technically competent people, those issues that you describe sound like really hard problems, but they are simply challenges that have been mitigated or solved.

    1. Rod – Thorium advocates are nuclear advocates first. There is not much advantage in offering inadvertent “helps” to the nuclear opposition.
      When your favorite technology (Thorium LFTR) has sat on the sidelines for four long decades without good engineering justification it is just a little hard to wait.

  6. This is a little inappropriate, Cyrill.
    While it might not show on the video, Dr. Kiki is expecting and is very pregnant.
    I think it is extraordinary how well Dr. Kiki did in conducting the interview with Kirk Sorensen.
    Cyrill, my friend and talented rouge scientist in chief, you have once again fallen off the deep end.

    1. “Little inappropriate”? It is wildly inappropriate, particularly in these pages and should be removed by the poster, or failing that by Rod.

  7. I guess there are more altenatives for nuclear power technology and we do not have to think in just nuclear alternatives.
    For example the experimental Cavitational Reactor in Bratislava eats (annihilates) everything including dustified radioactive materials and during this it has a very high output in temperature similarly than a nuclear power plant but while a nuclear reactor produces dangerous materials, it removes them.
    Gravitational energy converter is the other one. It is like a hydroelectric station but without water so it could be established under the surface invisibly. It converts stired masses’ inertia into turning-moment. It is modular so a “gravitational power plant” is composed by many similar modules and it has no ecologically dangerous product. So before its modular structure, it cannot be fully malfunctional.
    It is very important to think in bigger perspectives.

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