By Mark Halper
Posting in Cancer
Reactors based on thorium, not uranium, can solve nuclear power's waste and weapons problems, say some experts. No they can't, say others. Mark Halper's latest report from the thorium trail.
So. You've been hearing a bit about this thorium stuff, and how it augurs a safe nuclear future, have you? Certainly you have if you've been paying attention to my energy blog here on SmartPlanet, where I started banging the thorium drum last summer, and have written several accounts since then. Earlier this week, I told you about a thorium reactor that India plans to build.
For those of you new to this, and for a quick review: Thorium is a substance that could replace uranium as a nuclear fuel because, its supporters say, it does not yield nasty, weapons-grade waste the way uranium does. And its waste lasts for only a few hundred years, not the tens of thousands associated with uranium. It can work in conventional, water-cooled reactors. But when combined with alternative reactor designs, like a "molten salt" or "liquid fluoride" reactor, it offers even more advantages including greater efficiency, Flibe Energy claims. The U.S built a molten salt reactor in the 1960s at Oak Ridge National Laboratory, but the Nixon administration halted thorium development in favor of more weapons-prone uranium.
But is it really all that good? If it is, why aren't we doing it? What's the catch? These are all great questions that the thorium camp knows it must invite and answer before the thorium ship sails. Last week they were certainly on the mind of one detractor - Arjun Makhijani, president of the Institute of Energy and Environmental Research and an ardent believer in solar power - who took to the national airwaves in the U.S. to rattle the thorium dreamers.
In a 20-minute segment on a National Public Radio show hosted by NPR's Ira Flatow, Makhijani grilled one of thorium's most visible supporters, author Richard Martin, who has just written a book called SuperFuel, due out in June from Palgrave MacMillan. You can read the full transcript of their debate, and also listen to it, via the link in the previous sentence. Here's a taster:
Makhijani does not believe that thorium is a panacea to the waste and weapons proliferation challenges of nuclear.
"It doesn't solve the proliferation problem," he tells Flatow, noting that thorium reactors yield uranium 233, which can be used to make weapons.
"It doesn't solve the waste problem, either. So every nuclear reactor, no matter what type, creates fission products, which are highly radioactive materials, some short-lived, some long-lived, to make energy.
"With the present reactors, we create about a ton per reactor, per year. If you have a more efficient reactor, at least you will create half a ton, probably eight-tenths of a ton, nine-tenths of a ton. This is highly radioactive waste. If you look at Oak Ridge's current evaluation, they say you have to condition this waste, you have to convert the fluorides, and then you have to have a deep geologic repository."
He also notes that the waste includes long lasting technetium-99, among other radioactive elements, which poses cancer risks when used medically.
"When we talk about the waste, one of the things that skeptics of the liquid fuel thorium reactor ignore is the fact that because the core is a liquid, you can continually process waste, even from existing conventional reactors into forms that are much smaller in terms of volume, and the radioactivity drops off much, much quicker. We're talking about a few hundred years as opposed to tens of thousands of years.
So to say that thorium reactors, like any other reactor, will create waste that needs to be handled and stored, et cetera, is true, but the volume, we're talking tenths of a percent of the comparable volume from a conventional reactor. And not only that, but we've got all that waste from our existing nuclear reactor fleet, just sitting around, and we've got no plan for it.
And so we're talking about building a reactor that can process that into forms that are much, much easier to deal with."
The SuperFuel author also says it's highly unlikely that uranium 233 would end up in the hands of bomb-making terrorist. He notes that in a liquid thorium reactor,
"There's no point at which you can divert material. There's no material sitting in a warehouse somewhere, getting ready to be put in the reactor and so on. And to be able to obtain that material, you would have to somehow breach the reactor, shut it down, separate out the fissionable material and get away with it.
"And as I say in 'SuperFuel,' the book, good luck with that. But the other point is that even if you did manage to do that, the uranium-233 is contaminated with yet another isotope, U-232, which is one of the nastiest substances in the universe, and it makes handling and processing and separating out the U-233 virtually impossible, even for a sophisticated nuclear power lab, much less for a rogue nation, or terrorist group or someone of that ilk."
Makhijani counters by citing a Princeton University paper that says there are easy enough ways to bypass handling the uranium 232, to get to the uranium 233 for weapons making purposes. He also plugs another form of "nuclear" power: Solar energy. The sun emits heat from its own ongoing fusion of hydrogen isotopes.
"I have a favorite molten salt reactor," Makhijani says. "My reactor is free. It's in the sky, 93 million miles away. You can store its energy in molten salt. It is being done today. You can generate electricity for 24 hours a day....
"I don't know why - I'm still trying to understand why photovoltaics are still so expensive in this country. But you know Germany - I was at a seminar yesterday at the Heinrich Boll Foundation about the Germany decision to get out of nuclear. They're going to have a completely renewable system maybe by the time thorium reactors become commercial."
The thorium debate is just beginning - or re-beginning, given its decades-old history. Watch for more discussion from me over the next several weeks, as I continue my journey along the thorium trail, examining its tremendous potential and airing other views, writing from London, Chicago, and other stops. I'll even include criticism from another alternative nuclear camp: Those companies that are developing what's called fast neutron reactors, such as what Bill Gates' TerraPower is doing, and what San Diego's General Atomics is also working on.
Feel free to weigh in with comments below, or write to me through the email link.
Photos: Makhijani from TidesMomentum via Flickr. Martin from superfuelbook.com.
More alternative nuclear on SmartPlanet:
- Safe nuclear: India's thorium reactor
- Joint U.S., Iranian nuclear peace plan hatches
- Fusion breakthrough
- Nuclear’s back. Oh no it isn’t! Oh yes it is!
- China grabbing up uranium to secure nuclear lead
- Nuclear down, CO2 up in Japan, Germany
- Fukushima’s lesson: ‘Alternative’ nuclear, not ‘no’ nuclear
- Watch replay of nuclear’s future, with dash of rare earth
- Why safe nuclear will rely on rare earth minerals
- Meet the future of nuclear power: 8 guys in China
- The new face of safe nuclear
And a handy guide to alternative nuclear:
May 10, 2012
do you know the latest, global warming scare, oxygen levels going down due to burning fossil fuels, that's right running out of oxygen, so if your worried about global warming we better get a move on, and LFTR is the way it must go, LFTR is reliable, predictable, cheap, safe, inexhaustible, and its proven that it works, so lets stop dithering and stop pursuing fantasy stuff like fusion, Germany is proving how hard renewables are to control successfully, yes germany is having regrets about renewables, all the billions and what have they done, is create a chaotic expensive disaster of a power grid, LFTR to the rescue
Everyone must have forgot the energy source we use today is filthy and dangerous. Many lives are taken in production and excess death and the pollution spews forth cancer, heavy metal waste, benzene and photochemical smog and so on. Wide spread ecological disaster. Ruination of habitat and countryside. Coal and oil are better used for feed stocks not fuel. Those who use you as a unlimited source of monopolistic wealth ( ultimately the souse of fuel is not relevant when you own the infrastructure for distribution ) are not interested in cheap. So buy the high priced items like solar or oil or coal. Fear is something that manipulates the word into the hands of those who already own you (your already bought and paid for). So compare the alternatives in a fair manner solar energy is not free it works for some sure but it costs.
I think Makhijani might be referring to this paper on Uranium-232: http://www.princeton.edu/sgs/publications/sgs/pdf/1_3-4FetterA.pdf Uranium-232 is produced as a parasitic byproduct of the breeding process in the thorium fuel cycle. It is also a decay product of Uranium-233. What really hurts is that very minute quantities of it can make the whole pile of Uranium-233 very hazardous to people and electronics. Because the quantities are tiny, centrifuging out all the U-232 takes a considerable amount of Separative Work Units and time, during which more U-232 is produced from decay. You could potentially ignore the U-232 and still make a bomb, but you'd be killing the reactor's fuel cycle in doing so because the amount of uranium-233 produced by the thorium cycle is only barely enough to cover the initial fissile fuel used up in the process. Furthermore, forget about using any unshielded electronics or guidance systems in your bomb. Time and time again, nuclear opponents will downplay how difficult it is to actually build a nuclear weapon. There are many reasons why nuclear bombs are built with uranium-235 from very powerful enrichment systems and plutonium-239 from specially-designed breeder reactors incapable of producing electricity. We've known about thorium for a long time and it was killed in favor of plutonium.
"Clearly it's not the right thing to do or everyone would be already doing it." As well as being a prominent theme from Atlas Shrugged, this is some of the most faulty circular logic ever. There are reasons that molten salt reactors are not abundant. I will elaborate. The anti-nuclear industry, like Dr. Makajani, is against it because they are against all nuclear. The concept of very good or much improved is lost because it is not perfect. Their solutions are not perfect either but that's a discussion for another day. The pro-nuclear lobbies are largely against molten salt reactors also because the majority of their money is made creating, maintaining, transporting and generally taking care of fuel rods. In other words, they are heavily invested in the status quo. Private industry cannot take charge and forge on because they know that government regulatory agencies can impede or even bankrupt them over the initiative. So as you see, the problems with MSRs are currently more political than technical. It's going to take someone like India to prove the principles and demonstrate effectiveness before the United States will move forward with a plan that would be a benefit to us all.
Mark, thanks for covering the Science Friday segment. I think that my last couple of comments summed up the problem with the hairsplitting of anti-nuclear advocates like Dr Makhijani. We can have arcane debates over protactinium and the build-up of U232 for the next 20 years, but my question is "What do you propose to to in the meantime?" The larger picture is that the thorium revival is happening, it's inevitable, & it's going to be led by countries like China & India while the US sits out the largest energy technology breakthrough since advanced drilling. The objection of the nuclear power industry -- "If this was so great, we'd already be doing it" -- doesn't hold water as I demonstrate in SuperFuel, the book (superfuelbook.com). We need to move forward. Obstructionist scientific hairsplitting doesn't help us do that.
Both sides seem to know everything - using words like cheap, save, inexhaustible, only 100 years, easy to make weapons from, impossible to make weapons from etc.. If it was that cheap and that easy why isn't every country and every larger energy company already using it for decades? Why do so many people so quickly believe that they have found the solution to any problem? Because it is so very simple? Because it proofs all the people that demand to change our life-style wrong? I have modeled the interconnections as they can be found in your posts so far: https://www.imodeler.info/readonly?key=3DnLcJ2CEeG8_qwsFJzWkQ&id=afb3ca9a-c926-41c7-ba13-2334f7b12687 The insight matrix shows how weak or strong the arguments seem.... Happy modeling Kai
The answer is so simple, it's painful to try to understand why it isn't recognised by those that matter. We are in a world of ever more scarce and expensive hydrocarbons, which will run out as an energy source in their own rights and as a back up source for renewables. The prospects for maintaining peace and prosperity rests on the inevitable global deployment of breeder reactors; it needs to happen sooner rather than later. The arithmetic for breeder reactors proves that the technology does exactly what will be required, free of greenhouse gas emissions, with ease. Breeder reactors are inherently safe (that means walk-away safe - they shut themselves down according to the laws of physics, even under a common-mode failure, as happened at Fukushima). Breeder reactors work on a closed fuel cycle to 'burn' over 90% of the energy in the fuel as opposed to the 1% burned by the PWRs currently used. Breeder reactors can burn all of the world's plutonium, spent fuel and depleted uranium stockpiles to produce electricity whilst making the 'problem' of nuclear 'waste' disappear. Breeder reactors produce only a tiny fraction of the waste from present day reactors and the radioactivity of that waste decays to background radiation levels in 300 years - easily, cheaply and safely capable of storage. http://lftrsuk.blogspot.co.uk/2012/03/breeder-reactors-it-is-but-will-it-be.html Breeder reactors can supply all of the energy (including liquid fuels for transport) to every individual on the planet (at developed world standards) for all of time (from inexhaustible uranium and thorium deposits).
Seems to me that there is plenty of room to go full steam ahead with both thorium AND solar research and dissemination to see what wins out in the "real" world. We're not talking about either approach being fatally flawed by any means, rather it is a discussion of comparative advantages: as one technology develops and is refined, so will the other one, and only time will tell who gets the upper hand in the long run. My guess is that both have a place in our future, and both are hugely advantageous over the centralized pressure water reactors that use uranium, processed plutonium and other insane fuels whose benefits are greatly exceeded by their risks. If more countries took the path of Germany and Japan, we'd all have more resources to mature these technologies and be better off.
Unless there has been a breakthrough in the technology, I understand that photovoltaics are big users of rare earth elements. A major bi-product of mining thee is - Thorium . Because Thorium is radioactive, this waste is very problematic, so finding a productive use for it would be very helpful. Rare Earth mining is almost exclusively controlled by the Chinese, which might also be seen as a vulnerability of a technology upon which to base your future energy policy - Thorium, however, is plentiful everywhere.
Sorry, but Arjun Makhijani didn't make good arguments against Thorium. First he says it doesn't solve the proliferation problem. Well, not to 0%, but it does reduce the risks enormously. Second, he says there is still waste. Well, again, yes there is some but much less and Thorium technology can use up existing waste. We don't live in a perfect world. To reject something because it's only very good, not perfect is silly. Besides this, his alternative of solar isn't a solution at all. Maybe in the future solar can provide us with enough energy to run the planet (doubtful) but we need a safe, clean, cheap solution within 5 years or our planet, especially our oceans are going to be ruined. Thorium is the only realistic great alternative we have. Cheers from http://thoriumforum.com
For starters, everyone has their "theory" on what the hazard levels are on these things. If I recall there was an article reflecting on the R&D of the atomic bomb and Thorium or another material was first tested as a candidate and as the article above states, thorium was passed over due to the inability to make weapons grade materials with it in a realistic fashoin. Anything that is used for this that is "radioactive" is going to have byproducts, thorium at least is a lower grade alternative to the uranium class of reactor. If it is safer, make small reactors, put them in areas that are low impact... put more of them out there. Stop trying to build another 3 Mile Island or Chernobel. Japan needs to tear theirs down before they kill all of us.
I would love for this to be the solution that it's being touted as, but if it were, I don't think the energy companies would be so hesitant. Until now I haven't read the other side of the story. I'll be keeping up... thanks for doing the reporting.
The easiest way to separate the U233 from the U232 is to strip the Protactinum-233 chemically before it decays into U233 and becomes chemically inseparable from the U232. However, as earlier writers have pointed out, this is essentially robbing the reactor of its fuel stream so it will stop operating before enough U233 is extracted to build a bomb. This could be remedied by pumping U235 into the fuel stream to replace the lost U233. But this would require isotopic separation-- since the introduction of *natural* (unenriched) uranium would absorb too many neutrons in the U238 fraction of the natural uranium. To summarize, ANY neutron source equivalent to 20 megawatts of fission heat can provide enough neutrons to breed about one bomb worth of nuclear weapons material in one year. But it would not be cost-effective to do so using Thorium/U233. For all the effort it would entail, you would be better off just smuggling natural uranium into a clandestine enrichment facility and making a pure U235 weapon. This is what we call "proliferation resistance." Thorium is not proliferation-proof, it is highly proliferation-resistant, if the fuel cycle is managed the right way. And that is an improvement over what we have now.
I agree that global deployment of fission breeder reactors is *almost* inevitable--the only alternative would be if fusion reactors happened to come online first, and that now seems very unlikely-- but we sure are taking a long time to get around to it-- largely because of fear, and politics. Western nations appear to be comfortable enough with the way we have locked in our supply-chain of fossil fuels that we are willing to keep riding the Petroleum+Coal Titanic until it hits the Peak Oil barrier and sinks... and when a people are comfortable and complacent, they fear change. Therefore it will take a "hungry" nation, one that is growing and that has NOT yet finished building its industrial energy infrastructure on fossil fuels, to make the transition to breeder reactors. Obviously, China and India will be the new world leaders in energy. Bill Gates has pointed this out also (if you read between the lines of his TED talk on breeder reactors.)
because it turns out the MOX fuel that it produced was in Reactor #3 and has been even more dangerous in this kind of accident than the fuels used in the other reactors. Is this the kind of breeder reactor you are so excited about?
China does not have most of the world's rare earth minerals. For a brief period of history (about ten years), they have had a near-monopoly on world *supply* of rare earths because they subsidized their industry and drove the prices so low that USA, Canada, Australia, and other rare-earth suppliers could not compete and stopped producing. But let the prices of rare earths go a little bit higher, and you will see there are plenty of rare earth minerals not yet owned by China... Incidentally, the world's largest supplier of rare earth minerals until 30 years ago was-- CALIFORNIA. And the California minerals have not disappeared, they are still there. But environmental legislation made it more expensive to mine thorium and rare earths in California at the same time that China was ramping up their rare earth industry, so the California mine closed down... for a while.
It's not as wonderful as they say. There is no hard evidence yet that thorium reactors will be cheaper and safer than existing nuclear power plants. However there is ample evidence that thorium will be more proliferation-resistant, and that, combined with proliferation-resistant fuel-reprocessing, will greatly reduce the amount of nuclear waste created. So it is probably the best alternative we have among many alternatives.
That was not the kind of breeder reactor we are excited about. Not even remotely close to the same technology.