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By Robert Rapier on Aug 30, 2012 with 19 responses

Carbon Trading & Thorium Reactors

In this week’s episode of R-Squared Energy TV, I answer two viewer questions. The first is on California’s upcoming carbon trading markets, which includes a discussion on resource shuffling. The second question is on the potential of thorium nuclear reactors.

Readers who have specific questions can send them to ask [at] consumerenergyreport [dot] com or leave the question after this post (at the original source). Consider subscribing to our YouTube channel where you’ll be able to view past and future videos.

Link to Original Article: Carbon Trading & Thorium Reactors

By Robert Rapier

  1. By William McCullough on August 30, 2012 at 5:12 pm

    Mr. Rapier,

    The fuel fabrication for thorium reactors is not costly.  Thorium oxide mined from the earth can be put straight into a liquid fluoride thorium reactor (LFTR).  Thorium is about 4 times more abundant that uranium 238.  Thorium is about as abundant as lead.

    A LFTR works by converting the fertile thorium into fissionable (burnable) uranium.  Both the thorium and uranium are mixed with molten salts that allows the reactor to pump the ‘fuel’ around for processing and heat transfer.

    A LFTR has many advantages over a light water reactor; however, there are  two main features that contribute to its safety:  1) since the ‘fuel’ is liquid, the reactor is ‘self-regulating’.  As the reactor heats up the molten salt expands and moves the uranium away from the core; thereby slowing the reaction. 2) liquid fuel allows a ‘safety plug’ (made of the same ‘fuel’ salt with a fan blowing across it to keep it solid) to be installed on the reactor.  In the event that  the pump circulating the fuel stops or the reactor needs to be shutdown, the fan stops blowing, the molten salt melts the ‘plug’ and drains into a tank designed for maximum heat transfer.  This ‘drain plug’ is walk away safe since it depends upon gravity to work.

    This is a great advantage over light water reactors.  They all require some kind of active cooling and hence some kind of generator to run the cooling.  This is what failed at Fukushima.  The tsunami wiped out all of the back up generators that would have cooled the solid fuel uranium.   A LFTR in the same scenario as Fukushima would have had no problems.  The molten salt fuel would have drained into their tanks and solidified back to crystal salt in the tanks.  Once the danger was over, the Japanese could have heated the drain tanks and pumped the molten salt back into the reactor to restart it.  This technology was demonstrated at Oak Ridge National Labs in 1965 – 1969.  At Oak Ridge the technicians would shut off the reactor over the weekends this way and restart it on Monday.

    I recommend that you read Dr. Richard Hargraves book called “THORIUM: energy cheaper than coal.”  The book was published just last month.  He runs through all of the competing energy production technologies, prices them, and discusses how thorium can be cheaper than all of them.  The book’s website is  It is available on Amazon.

    Best regards,

    William McCullough

  2. By Random Lurker on August 30, 2012 at 6:06 pm

    After reading a bunch of pro Thorium articles a year or so back, I also wondered why it hasn’t been commercially successful if it’s truly as superior as proponents claim (and has been fairly well understood for nearly 50 years).  So I did a very quick google and easily found a slew of articles that seem to directly contradict many of the claims made by the pro-Thorium crowd.  Here is one example from a very well respected organization

    I’d like to hear a true Thorium expert respond to the claims in this document.


    The other thing is that a significant percentage of the pro-Thorium articles seemed to include a very faint but detectable whiff of conspiracy to them.  Many of them included verbage that implied ‘If only big-oil/big-uranium/government/the UN/etc would stop suppressing Thorium we’d all have clean nuclear energy that is nearly too cheap to meter’.  That type of stuff  always sets my baloney detector into high gear.


    I really do have an open mind about it.  I appreciate there absolutely is great potential there.  I just would like to hear the response to critics, and of course, I’d really like to see the results from a functional, near-industrial sized reactor before I hop fully on board.  I mean hasn’t India been pursuing commercial Thorium power for years with very limited success?


  3. By Terry on August 30, 2012 at 6:59 pm

    This radio segment on NPR’s Science Friday had a decent little discussion on the pro’s and con’s for Thorium reactors.

    • By Random Lurker on August 30, 2012 at 8:48 pm

      Thanks for the link.  That was almost exactly what I was looking for.


      After listening to it, my layman’s takeaway is that it sounds like LFTRs do indeed solve the meltdown problem, but they probably offer only marginal benefits to waste and proliferation issues compared to current Uranium based reactors.  Honestly sounds more like an incremental improvement over current nuclear technology as opposed to anything revolutionary.  Something I’m certainly interested in seeing explored further, but nothing that would seem to ‘change the game’.


      Thanks again for the link!

  4. By Emmanuel Walter on August 31, 2012 at 9:13 am

    Thorium MSR is indeed the Magic bullet to solve all our energy problems. It also burns Uranium waste solving the issue of big piles of Uranium waste. Also, as it is a hot reactor (around 750 C vs 350 C for Uranium), you can use the generate heat to desalinate water or produce Ethanol/reduce CO2.

  5. By notKit P on August 31, 2012 at 1:57 pm

    Light water moderated reactors using enriched uranium are very good at providing energy for naval propulsion and making electricity.  This is why I know a lot about BWR & PWRs and nothing about thorium reactors.


    The mistake most make when comparing ‘advantages’ is not using numbers.  For example on safety what is the risk of releasing fission products to the environment in an amount of that could hurt people.  For LWRs, that risk is around ten to the minus 9th.   If you someone is saying  safer is around ten to the minus 12th  then three orders of magnitude sound like big improvement but in absolute terms it is one very number compared to another.  LWR are walkaway safe too.


    Every power plant in the world is subject to assets being destroyed.  If the EPA comes up with new regulations for say dealing with coal ash, the asset value of the coal plant could be destroyed. 


    The human mind has a problem conceptualizing very small numbers.  The O&M cost for LWR is $20/MWh or 2 cents/kwh.  This includes taxes, fuel cost, spent fuel disposal cost, and decommissioning. 


    Most of us can understand 2 cents/kwh.  Of this only 10% is the cost for associated with fuel.   My point here is there is not a lot of  potential of cost savings with thorium.

  6. By Russ Finley on September 1, 2012 at 12:24 am

    Random Lurker said:

    “…my layman’s takeaway is that it sounds like LFTRs do indeed solve the meltdown problem, but they probably offer only marginal benefits to waste and proliferation issues compared to current Uranium based reactors.”

    Conventional reactors are adequate. There is no waste or proliferation”problem.” You don’t need a commercial power plant to make weapons grade material. All you need is a reactor. Just ask Israel.
    The waste from a half century of nuclear power production fits inside the power plant parking lots. That small volume can be reduced by an order of magnitude with reprocessing.  The waste issue has been blown out of proportion by the same groups who won’t allow our government to build a repository for it (forcing it to be stored on site).
    Meltdowns are very rare, and have killed fewer people than any other power source we have. Modern passive designs can make meltdowns statistically insignificant.

  7. By Allan Feinstein on September 1, 2012 at 1:44 pm

    What people have a hard time evaluating is a very small probability of a very large disaster.

  8. By notKit P on September 1, 2012 at 4:00 pm

    “Meltdowns are very rare, and have killed fewer people t”


    Core damage has occurred at 4 commercial LWR. No one was even been hurt by radiation.


    It is not credible to kill a member of the public with a commercial LWR. It is credible that an reactor accident could kill an employee at a nuke plant. Design of the reactor and training has precluded that to date.


    It is not credible for a LWR to cause a ‘very large disaster’. This not to say that the media will not label every accident at a nuke plant a disaster. This brings us back to alternative reactors. While a design with passive features may preclude some types of accident this will not make a difference when dealing with the media and antinuclear activist.


    The reason that LWR are safe and can not cause a large disaster is that they are water moderated and housed in a reinforced concrete building. LWR shutdown and stop producing power when the water moderator is lost. Chernobyl was a disaster in terms of loss of life because design allowed workers to be killed almost instantaneous. However, most of the workers and firefighters killed by radiation as a result of stupidity. Chernobyl was a disaster in monetary terms because the lack of containment allowed the fire to spread fission products over a larger area.

  9. By Ed Reid on September 2, 2012 at 6:23 pm


    Regarding the CA carbon allowance market, the state obviously looks upon carbon emissions allowances as a cash cow. The US Congress viewed carbon allowance sales or auctions the same way. However, it is very important to realize that, while the requirement to purchase allowances from the government would raise revenue for the government, it would also add to the total cost of carbon emissions reductions, while contributing nothing to the capital investment required to actually reduce carbon emissions. Electric utilities would be especially affected for the following reasons: large total emissions; non-commercial emissions reduction technology; long regulatory approval times; long construction periods; and, the ability of other emitters to switch to electric power from direct fossil fuel use, thus transferring their emissions to the utilities.

    California’s non-utility businesses would probably shift to electric processes, where technically feasible and cost effective; and, move out of state, or out of the country, when such a fuel switch was not technically feasible or economical. The utilities, on the other hand, have nowhere to go.

    • By Tom G. on September 2, 2012 at 8:45 pm

      Ed said in part:

      “The utilities, on the other hand, have nowhere to go.”  

      I guess we could add the following – and therefor electric rates for consumers will necessarily increase.


      • By Ed Reid on September 3, 2012 at 6:25 am


  10. By Tom G. on September 3, 2012 at 4:25 pm

    O.K. so “Carbon Trading & Thorium Reactors”.  Since I don’t think that carbon trading is the solution to our glut of carbon I won’t comment on that portion of this story.  That leaves me with Thorium Reactors to talk about.  

    I don’t know much about that subject either since most of my 20+ years of experience in the nuclear field was limited to Pressurized Water Reactors [PWR's] which are quite different.  In addition, I am further limited in my knowledge by my career choice which was to become a Quality Engineer.  Basically what Quality Engineers do is watch other people work and determine if their work meets established quality standards like those published by Federal and State governments.  Quality Engineers do design reviews, approve work plans, check cost feasibility, determine process capabilities and assure work is completed to existing industry and Code standards like AWS, IEEE, ANSI, ASTM and API.

    So let’s talk about what we have to do to implement a LFTR design for a minute.  When it comes to what the industry calls “the secondary side of a power generation station” which contain things like the turbine generators, condensate pumps, motor operated valves, heat exchangers, and economizers; most of that stuff hasn’t changed much in the last 50 years.  However, when we marry this equipment to a new LFTR design; most of that equipment will need to be redesigned to work with the higher temperatures we can use with the LFTR.  This will of course cost hundreds of millions of dollars but the higher operating temperatures means higher efficiency so someday we could see a return on that investment.   

    Most of the above redesigns are what I would call MINOR when compared to what is going to happen working backwards from the main steam stop valves into the reactor coolant system.  That is where we will probably be spending hundreds of billions; designing, constructing, testing, redesigning, retesting and then finally licensing a new design.  Then some adventuresome nuclear company will try to convince some utility to build one but tat utility would of course only consider such an action if the government guaranted the loan.  This whole process is going to take at least 10-15 years and then another 5-10 years before we get around to pouring concrete at some utility location.  That is of course if we have been able to eliminate the legal challenges by the NIMBY crowd which could take 5 more years.

    What is inferred in the above paragraph is that we will probably all have gray hair before one of these new LTFR plants get’s approved for construction.  In addition, if you haven’t checked the cost of construction lately you probably should.  Even something as basic as the cost concrete which once cost $30/yard now costs over $120/yard.  There isn’t a single utility or consortium of utilities that could afford to design and construct a new LFTR plant.  What that means to me is that if something like this is to occur, the public would need to be calling in mass their congressional representatives and demanding government intervention.  Most of the time what I read is that 70-80% of the American people want a continuing focus on renewable energy, conservation and energy efficiency.    

    So yes, the LFTR design certainly has potential.  However, the same could be said of Small Modular Reactors, Traveling Wave Reactors and Breeder Reactors.  Do we need the LFTR design right now; I really do not know.  How much will wind, solar, hydro, geothermal, bio-mass, waste-to-energy and battery technology cost in 10 more years? 


  11. By Tapio Peltonen on September 3, 2012 at 5:42 pm

    AFAICT, there are numerous challenges in building high temperature molten salt reactors, and this is why we are unlikely to see them commercialised – at least not in a large scale – anytime soon. But I’m fairly sure that if the engineering hurdles can be overcome, LFTR-style designs hold an enormous promise, mainly because of the strongly negative thermal coefficient of reactivity, which means they can be easily throttled to match demand. They might work extremely well as a complement to solar and wind; they could be cranked up nighttime and during calm weather and idled whenever solar and wind are plentiful.

    Actually, a liquid fuel reactor could be run on uranium as well. It’s more about the reactor design than about the fuel. I think the main reason they did not get commercialised in the past was that the whole concept was so different from all previous reactor designs that none of the conventional nuclear reactor expertise was any good for them and  that to be viable they would have needed to make a couple of material science breakthroughs to prevent corrosion of the reactor chamber structures at the sustained high temperatures. I am all for continued research and development in nuclear power and LFTR is one of the most exciting ideas that are floating around, and certainly one of the most radical ideas that might actually become reality. But it’s still in its early stages, and huge showstopper issues might still come up.

  12. By notKit P on September 4, 2012 at 5:56 pm

    Tom, I see no reason for Balance of Plant (BOP) to be more expensive for a LFTR than  LWR for which I have 40+ years experience.  The reason is that a steam plant is a steam plant.  The applicable BOP code is ASME B31.1, 2004, “Power Piping, ASME Code for Pressure Piping” for the new reactor that I am working on.


    Steam plants have changed in the last 50 years just not that much for nukes.  The limiting factor for a nuke plant is fuel rod cladding temperature (10CFR50, Appendix K).  Nuke LWRs generally produce saturated steam at a lower pressure than modern fossil steam plants.   My fist steam plant was WWII vintage destroyer which was identical to my fist navy nuke steam plant.  When building new nukes, the navy had to go back and find an old steam plant design. 


    Over the years the fossil industry was been pushing the design envelop with higher temperatures and pressures.  LFTR will not challenge existing BOP design.   


    “spending hundreds of billions”


    More like 10 billion for a first of a kind reactor.  We can always get the France, Russia or China to partner with us too.  It is not like nuke reactors are state secrets anymore.  If a prototype is built in the US it will be built someplace like Idaho by DOE.  There is an open season on NIMBYs in Idaho. 


    While I am skeptical that anything but large LWR will be the choice for 9 of 10 commercial reactors for the next 20 years, the cynic in me bets even money that I could be working on some alternative because the government has cash that my company can harvest. 


    “mainly because of the strongly negative thermal coefficient of reactivity, which means they can be easily throttled to match demand.”   


    LWR are very good at following demand.  France uses nukes to load follow.  On navy nukes demand controls reactor power.  The reactor operator just watches power change when we would go from all stop to ahead full.


    The concept that most do not get is that producing power is a responsibility.  When our customers demand power they really do not care how the engineers do it.  For me it all interesting so I am lucky to get paid to do what I like doing. 

  13. By jeffry on September 7, 2012 at 1:29 am

    The fuel fabrication is costly? Get your facts dude!!

    Its uranium that need to undergo lots of steps to prepare it as fuel, Thorium in it natural form can be used just by adding it to a liquid salt.

    • By Robert Rapier on September 7, 2012 at 1:44 am

      Everything I have read about thorium contradicts what you just wrote. It is not fissile in its natural form, and so it is not directly usable until a fissile material is present that provides enough neutrons to make it fissile. 


  14. By Jo . Whistler on October 17, 2012 at 6:52 pm

    Public risk is a concern in the nuclear industry.  The evaluation of risk is best assessed and carried out by the Insurers of the world.  Under this even my home and other insusrance policies have a nuclear exclusion clause – nuclear is not assessed as safe and governments are forced to underwrite the nuclear industry and bear the ultimate cost .

    Would the Thorium industry be able to carry its own insurance or would it be compelled to seek the goverbnment to underwrite an immense public risk. 


    j. Whistler


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