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  • #1075
    mjv1121
    Participant

    I know there is already a thorium thread, but I thought this news was worthy of a new thread.)

    On Tuesday 25th January at the Chinese Academy of Sciences annual conference it was announced that the People’s Republic of China has initiated a research and development project in thorium molten-salt reactor technology.

    I am aware that many people reading this are strong fusions advocates and may well consider fission only in terms of radioactive waste, nuclear accidents and proliferation. Be under no illusion – energy from thorium in a molten salt breeder reactor (aka Liquid Fluoride Thorium Reactor – pronounced LiFTeR) is an remarkable technology – it’s what nuclear fission power should always have been. Its safe, its non-proliferating, can beat coal on cost, reactors can be factory mass produced, fuel costs are negligible, its very scalable – from 10MW to multi-GW, it has a small and valuable waste stream, no (carbon) emissions, it can burn/recycle ex-weapons material and help to remove the present nuclear waste problems, and ….IT WORKS!

    I have to confess to being a huge fan of molten salt reactors and LFTR in particular. A 1GW coal fired power station burns 4 million tonnes of coal each year. To power the world as it is today, we burn over 30,000,000,000 tonnes of coal/oil/gas a year – thats 30 BILLION tonnes – emphasis on the BILLION. And you can add to that 65,000 tonnes of uranium. By contrast, if ALL power systems were electrical, the world could be powered by less than 7,000 tonnes of thorium.

    The main (read funded) fusion options are tokamak (ITER) and laser inertial fusion (NIF), both D-T fusion. Both of these are likely to be very expensive to implement. The machines themselves need huge amounts of energy, which almost by definition means the machines must be huge, so we’re talking Gigawatt scale generating power plants – so no improvement to the current grid and transmission losses regime. The size of the devices though are dwarfed by their complexity. Confining fusion energised plasma using magnetic fields strikes me as an exercise in futility. And it ain’t go to be much easier firing D-T pellets into a multi-megawatt multi-laser focus at 10 times a second. Add to that the requirement to get in excess of 50% net energy and it all becomes rather….tricky!.

    Quite frankly, if I had to choose between the main D-T fusion options and LFTR, I would take LFTR.

    But don’t take my word for it, just ask the Chinese. The largest and fastest growing economy in the world is investing in thorium molten salt breeder technology. They are doing this not only for their own needs and because they recognise the advantages of thorium, but also they hope to be able to dominate a multi-trillion dollar worldwide energy business.

    The race is on to replace coal and oil, which are of course the real enemies. It is my hope that FF will get there first, but in light of the recent Chinese announcement, at least from a business standpoint, I wouldn’t be looking over my shoulder at the other fusion approaches, I’d be keeping my eye on thorium. Also, now that China has taken the lead, its quite possible that America/EU/Russia might start to take thorium/MSR more seriously, which if looked at from a funding point of view, is likely to mean even less chance of funding for “alternative” fusion projects.

    Of course, my favourite potential power technology is Focus Fusion: cheap, fully scalable, mechanically simple device, no waste stream and no expensive heat transfer and turbines.

    #9614
    Rezwan
    Participant

    That is great news! Also, I’m going to move this post to contenders.

    Yes, this is what Bill Gates was referring to in his TED talk.

    Although in that talk, he put the development of this technology at 20 years, and commercialization at 40. NIF’s latest estimate is 10 years to prototype, 20 to commercialization.

    It’s true that fusion has a difficult time growing in the shadow of Thorium or oil. If you talk to fusion scientists, quite a few put the development of fusion energy at 100 years and beyond – not because of the science, but because of the economic competition from first oil, then fission. Many of them figure fission will solve the immediate energy crisis problems, and then, in the usual trickling start/stop way it’s been going, fusion will eventually get developed without much fanfare.

    This is too bad, because for me, it’s always been about a lot more than the energy problem. It’s the ego thing. The cosmic dimension of trying to understand and control plasma – reaching into the heart of a star. The mythic, primal, questing, epic thing.

    I wonder how we can leverage this Thorium shadow to encourage fusion alternatives. As you point out, ITER is just too non-competitive. Fusion will need to present more appealing ideas. They have to play the “pleasant physics surprise” card. Start exploring those smaller, more nimble fusion ideas.

    #9615
    mjv1121
    Participant

    First of all, to state the obvious, I believe the most important thing is to move to an all electric society (which may or may not include hydrogen – incidentally LFTR would be great for process heat to extract hydrogen). In order to achieve that there we need a method of generating electricity that is considerably more viable than burning fossil fuels, both economically and environmentally. Thorium powered fission could certainly be economical and would be orders of magnitude greener than wind and solar.
    The problem with the present fission technology is the fundamental inefficiency of solid fuel and the subsequent considerable waste stream. Bill Gates is an advocate/investor in Travelling Wave Reactors – basically a variation on-a-theme of solid fuelled sodium cooled fast reactors like IFR. The big – very big – advantage with molten salt reactors is that they use liquid fuel – molten salt in fact . This turns a nuclear reactor from being a dangerous beast that must be controlled using “defence in depth”, into a reactor that is self-controlling and can be chemically processed. In addition thorium is far more abundant than uranium, certainly sustainable for a few hundred thousand years. All in all, a thorium powered world would be very very acceptable.

    The reason that D-T fusion will find it hard to compete is that there is no advantage – LFTR really is that good. A “pleasant physics surprise” card could be Aneutronic fusion, but even that is not much of an advantage against LFTR. What we need is a small, but scalable generator, that can be manufactured and implemented at a 90-95% cost saving…..focus fusion! I do think the fact that its the Chinese that have made this move could (maybe, possibly) be an advantage. It may motivate the powers that be to take a second look at alternatives. The problem remains though, that its not the decision makers that are the stumbling block, its the advisors to the decision makers.

    As a point of interest (and because I’m a MSR nerd), the molten salt is the same salt that is proposed to be used for cooling and heat transfer for tokamaks and LIFE. For fusion use it has the added benefit of making tritium, which is quite useful cos it doesn’t grow in the wild.

    #9621
    mjv1121
    Participant

    Some more facts and numbers to cheer or weep over:

    It seems that the biggest problem China has with coal, is transportation – the conventional rail system is working at capacity, so most of the coal is delivered by truck, leading to horrendous traffic problems.
    Apparently, China already has plenty of thorium stock piled – a “by-product” of rare-earth mining – currently they have no use for the thorium.

    “Hey, I’ve got a good idea. Why don’t we use the thorium to make electricity – its much easier, much safer and much cheaper than present nuclear and we can get that damn coal out of our transportation system.”

    but what about the cost?

    It looks like ITER will cost the best part of of $20 billion, which is quite a lot. Experiments are due to start in 2019.

    China is spending $300 billion by 2020 on its electricity powered high speed train network.

    I think its safe to say that the thorium reactor project will be sufficiently funded.

    #9691
    Rezwan
    Participant

    You say above that China has “initiated a research and development project in Thorium…” That tends to mean that it doesn’t actually work yet.

    How does their R&D schedule and issues compare to the Bill Gates proposal noted in the TED talk?

    Bill also enthused about the way Terrapower uses spent uranium and turns a problem into a solution, but then asks “Why haven’t we heard of this before” and answers himself with:

    Innovation really stopped in this industry quite some time ago. The idea that there are some good ideas laying around is not all that surprising.

    People had talked about it for a long time, but they could never simulate properly whether it would work or not, and so it’s through the advent of modern supercomputers that now you can simulate and see that yes, with the right materials approach, this looks like it would work.”

    Scale of Investment:

    Scale of investment: To do the software, supercomputer, hire great scientists – only tens of millions. Even once we test our materials out in a Russian reactor to make sure that the materials work properly, then you’ll only be Hundreds of millions. The tough thing is building a pilot reactor, Several billion, regulator, location. Once you get the first one built, and it works as advertised, then it’s plain as day – the economics, energy density are so different than nuclear as we know it.

    Time of investment:

    Time scale: 20 years to invent, 20 to deploy. [Fission in 40 years! Where have I heard that before – oh- fusion.] Terrapower, if things go well, which is wishing for a lot, could easily meet that.

    “If things go well.” Is there a similar uncertainty factor with the MSR’s?

    Bill seems to think that there is enough uncertainty in fission all around to warrant HUNDREDS of similar R&D projects launched. Perhaps Thorium MSR was one such. He says:

    There are, fortunately now, dozens of companies, we need it to be hundreds, who likewise, if their science goes well, if the funding for their pilot plants goes well, that they can compete for this. And it’s best if multiples succeed, because then you could use a mix of these things. We certainly need one to succeed.

    So, again, is Bill foolishly overlooking the already functional thorium reactor? Can he just drop the terrapower and go snap up a Thorium reactor today? I feel some information is missing here.

    #9693
    mjv1121
    Participant

    You say above that China has “initiated a research and development project in Thorium…” That tends to mean that it doesn’t actually work yet.
    – ORNL had a liquid fluoride reactor working for 5 years in the 60’s, and they demonstrated that it can burn all three fissile materials: uranium 233, uranium 235 and plutonium 239 – the R&D is really to do with choosing the right materials and design to use as a long term, reliable, “commercial” energy generator.

    How does their R&D schedule and issues compare to the Bill Gates proposal noted in the TED talk?
    – Molten Salt Reactor technology is way more developed than travelling wave reactors. In fact if you wiki TWR’s you’ll see that the concept of a “burning log of uranium” that you “fill-up and leave to burn” has already been abandoned.

    Bill also enthused about the way Terrapower uses spent uranium and turns a problem into a solution, but then asks “Why haven’t we heard of this before” and answers himself with: Innovation really stopped in this industry quite some time ago. The idea that there are some good ideas laying around is not all that surprising.
    – If you’ve ever heard the term “fast breeder reactor”, then you have heard of this before. In order to use uranium 238 as fuel you need to convert it into plutonium 239. To do this efficiently you need a fast spectrum reactor, ie fast/high-energy neutrons. So you are breeding plutonium 239 (which fissions (splits) and releases energy) from uranium 238 which does not fission. In a LFTR you breed uranium 233 (which fissions) from thorium 232 which does not. Uranium 233 fissions very efficiently in a thermal spectrum (read slow/low-energy neutrons) reactor. A more likely candidate for a fast breeder is IFR, which had received a lot of research in the US until the 90’s.

    Part of the problem with fast reactors and also with today’s light water reactors is the amount of fissile material needed to start them up, which is 4-5 times more than you need to start a MSR. Also thorium is 3-4 times more abundant than uranium. Assuming you had the will and the capital to build more LWRs and fast reactors, you will still be limited by the amount of plutonium or enriched uranium available to get them started.

    “If things go well.” Is there a similar uncertainty factor with the MSR’s?
    – China have spoken about a 20year program. Personally, I’d be surprised if they don’t have prototypes working in 5 years and starting deployment in the second decade of the program.

    Bill seems to think that there is enough uncertainty in fission all around to warrant HUNDREDS of similar R&D projects launched. Perhaps Thorium MSR was one such. He says:
    There are, fortunately now, dozens of companies, we need it to be hundreds, who likewise, if their science goes well, if the funding for their pilot plants goes well, that they can compete for this. And it’s best if multiples succeed, because then you could use a mix of these things. We certainly need one to succeed.

    So, again, is Bill foolishly overlooking the already functional thorium reactor? Can he just drop the terrapower and go snap up a Thorium reactor today? I feel some information is missing here.
    – He speaks in passing of problems with liquid reactors so I don’t know what he is referring to. As far as TWR’s are concerned, I suspect he has been seduced by the “light and leave it” scenario and by the prospect of using depleted uranium as fuel.

    There are two parts to the waste from LWR’s. One is the spent fuel from reactors and the other is the depleted uranium leftover from enrichment. Depleted uranium is not a worry as such, since it is “depleted”, ie it is less radioactive than when it was originally dug up. The difficulty with spent fuel is that it is in a form that is very difficult and expensive to work with and this is fundamental to the inefficiency, expense and large waste stream from solid fuel reactors.

    …..more to follow

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