I am someone who has been interested in the future of nuclear energy for awhile now. Recently a new type of nuclear reactor came to my attention, one I believe has a great deal of promise for humanity's future, so knowing TL is full of techies who might be interested in it, and after a thorough search revealed no other posts on this topic, I decided to make one. It is called a LFTR, a Liquid Fluoride Thorium Reactor, and it has many advantages over the current Pressurized Water Reactors (PWRs) which produce 99.9% of all nuclear power today.
The LFTR is a better design than the current PWRs for a number of reasons:
1) PWR's, as their name implies, hold water in a highly pressurized state. Water is held between 75-150 atmospheres of pressure so that it's boiling point can be raised above 300C, which is the only way to generate enough heat to make it viable for generating electricity. Since the LFTR uses molten salt instead of water as a coolant, and since molten salt does not need to be pressurized to reach high temperatures, the reactor can be operated at normal pressures, mitigating the possibility of explosions, meltdown, and environmental contamination. This is the single greatest advantage of the LFTR over current PWR technology.
2) Since the reactor operates in the 700C range, the temperatures are hot enough to use a gas turbine instead of the steam turbines other reactors use, vastly increasing efficiency. Because LFTRs use a gas turbine, the excess heat generated can be used to de-salinate seawater, essentially for free. This means that in addition to generating power, a LFTR can provide fresh drinking or irrigation water, instead of one or the other with traditional nuclear de-salination.
3) LFTR, as the name implies, uses a fuel known as Thorium, which is so abundant in the earth's crust that you can literally mine a ton of ordinary rock, and extract enough Thorium from that rock to power your life for 5 years. 5000 tons of Thorium would provide the entire planet's energy needs for a year, and there is over a million tons of Thorium in known deposits already on earth, and probably several times that much still undiscovered.
4) LFTRs do not produce the "spent fuel" problem of ordinary solid fuel reactors like PWRs. Because the fuel is a liquid it can be fully burnt up in the reactor, so storage of spent fuel is not necessary. Furthermore the projected transuranic waste of a 40MW "mini" reactor produced over ten years is anticipated to be only a few millionths of a gram. This is teeny tiny amounts of pollution.
5) LFTRs can burn up existing nuclear waste as part of their fuel cycle. So if you're concerned about nuclear waste and the Yucca Mountain depository, build LFTRs instead and burn it all up!
6) Since LFTRs do not use water as a coolant, they do not need to be located near a major river like PWRs. States like Utah or Nevada can go on a LFTR building spree, something they cannot do with PWRs. Furthermore, developing countries can build them regardless of their climate and water availability, and as mentioned above can even use them to generate drinking water or water for crops.
7) LFTRs were originally conceived in the 1950s as part of a "Nuclear Bomber" program the Air Force had. As such they were designed to power an aircraft, something a PWR could never hope to do for a number of reasons. Because of this LFTRs are incredibly safe. It is a dynamically stable system, meaning it self-regulates. As the salt heats up, it expands, touching more of the pipe surface. This begins to cool the salt, and it begins to contract, heating it up, and the cycle repeats. It is walk away safe. Unlike PWRs nuclear safety technicians could walk out the door and turn out the lights, and it would keep running safely without risk until it used up all its fuel.
8) A "freeze plug" is used as a passive safety system in the LFTR. A fan blows a cool gas over a portion of pipe containing the salt, freezing it solid. In the case that something goes wrong and power is lost in the reactor, the fan stops blowing, the frozen salt plug melts, and all the molten salt in the reactor drains down naturally by gravity into a storage container designed for that purpose. No explosions, no meltdowns, no radioactive contamination.
9) LFTRs are extremely proliferation resistant, overcoming another of the major objections to nuclear power as it is currently practiced. The reason for this is chemisty. Unlike all other nuclear reactors today which use either the U-235 or the U-238-->Pu-239 fuel cycle, the LFTR operates on the Th-232-->U-233 fuel cycle. This means that the LFTR is a breeder reactor like Liquid Metal Fast Breeder Reactors (LMFBR) but unlike LMFBRs it does not use fast neutrons, it uses thermal neutrons, which makes fission much easier to achieve, and the fluoride salt used in the LFTR is much safer and less reactive than the liquid sodium used in the LMFBRs. Uranium-233 is useless for making bombs, since it has a hard gamma emitter in its decay chain. This is manageable for containment and disposal but not for bombs that have to be designed and that sit in storage. The gamma emissions from the decay of U-233 will:
a) Damage your bomb's circuits b) Kill your staff working on it c) Show everyone in the world with gamma ray detectors where your bomb is (pretty much every developed country has them on satellites by now.)
Sound too good to be true? It did to me too when I first heard about it. Here are some links I recommend you check out if you want to learn more.
LFTR in 5 Minutes: (5 minute summary, full documentary follows after the credits)
The Thorium Dream (documentary):
Finally if you want to get involved in trying to make this a reality you can check out Energy From Thorium, the largest Thorium advocacy organization I'm aware of.
Flibe Energy is the only company I know of in the United States currently pursuing LFTR. If you have a few billion to spare, consider helping them out. + Show Spoiler +
On January 25 2012 10:32 EtherealDeath wrote: In a nutshell, if this was conceived of in the 1950s, why did they go and make all those PWRs?
Excellent question, and this is covered extensively in those two documentaries, but the short answer is that Thorium is useless for making a nuclear weapon, and in the 1950s at the height of the Cold War they wanted to generate power and make bombs, so they chose U-235 and the U-238-->Pu-239 fuel cycles, both of which can be used for electricity and for bombs.
I see you're from China EtherealDeath. You may be interested to know that China is currently the only country in the world actively developing LFTR technology. They anticipate their prototype LFTR coming online by 2022, and it is being spearheaded by Jiang Mianheng, the son of Jiang Zemin, who holds a PhD in Electrical Engineering from Drexel.
mmm, this does sound too good to be true. But it also sounds plausible.
If this stuff works out it could be a huge leap in electricity supply. The biggest issue with green power is that lack of proper storage systems which nuclear power totally circumvents. Time for a read...
On January 25 2012 10:47 Zaros wrote: Sounds to good to be true but if it is true will be a good energy source untill we master fusion.
I used to be the biggest fusion guy. I would read or watch anything I could find on it. Now I am inclined to agree with you. LFTR now, fusion when we master it (probably a few more decades,) matter-antimatter annihilation sometime after that.
In a nutshell, I bet this would get more responses if it was titled "girl invents unlimited power source." However the topic has been around here before, maybe just buried in other threads.
Truthfully I'd think that in the past these fission reactors with thorium weren't fully technologically feasible. It's too optimistic to say otherwise, there would have been years of development needed in the past before anything could really be built, while getting started on uranium fission plants was quicker. The understanding of how the nuclear reactions would work was there, but overall level of technology was such that cost would have been prohibitive and smaller scale reactors which could be built today simply wouldn't have been doable. It's equally important to remember the political pressure on nuclear power has always immense. A reactor design that would not cleanly lead to enrichment of fuel for weapons and was out-lobbied never was given the opportunity for significant research and development. Of course, it is regrettable the visionary choice wasn't made back then because we would probably all be better off now.
From where things stand today, real investment in this technology ought to yield results much more quickly. First world countries like the US could solve the problem effectively permanent electrical power (not going to run out of thorium) at costs that aren't discouraging, especially compared to other renewables. The main obstacle is that the current economic state of the world and political priorities of first world countries make any large scale investment in energy difficult. If the entire scientific and energy community was behind a new age of investment in nuclear power it would be tough enough, let alone competing with other energy lobbies and the effect of dividing up already small amounts of funds and subsidies that would go towards solar/wind/other renewable energy.
On January 25 2012 10:51 Crazy Eddie wrote: Truthfully I'd think that in the past these fission reactors with thorium weren't fully technologically feasible.
LFTRs are not an unproven technology. They have been built before. The Molten Salt Reactor experiment ran for over 3 years. Here are a few examples of LFTRs in the past:
I remember reading from one of those periodic tables w/ descriptions of elements that thorium ores were super abundant and could represent energy potential far greater than uranium. Glad to see it's being implemented, the question is when will it be widespread enough that coal, oil, and natural gas are no longer needed? And will the U.S. government be receptive to a power source that is not oil and that could unemploy its citizens (although the construction of the facilities will employ people at first).
On January 25 2012 10:51 Crazy Eddie wrote: From where things stand today, real investment in this technology ought to yield results much more quickly. First world countries like the US could solve the problem effectively permanent electrical power (not going to run out of thorium) at costs that aren't discouraging, especially compared to other renewables. The main obstacle is that the current economic state of the world and political priorities of first world countries make any large scale investment in energy difficult. If the entire scientific and energy community was behind a new age of investment in nuclear power it would be tough enough, let alone competing with other energy lobbies and the effect of dividing up already small amounts of funds and subsidies that would go towards solar/wind/other renewable energy.
And unfortunately that is politics the greatest disaster in humanities existence, i wonder if a name change and some PR work for nuclear energy would help at all?
This seems like one of those "to good to be true" things. If it really can do all that i would love to see a serious investment in the USA. OP because you knew that research was being done in china do you know if there is anything being looked into in the USA?
On January 25 2012 11:09 Deathmanbob wrote: This seems like one of those "to good to be true" things. If it really can do all that i would love to see a serious investment in the USA. OP because you knew that research was being done in china do you know if there is anything being looked into in the USA?
So far the only people in the US pursuing this is a company called Flibe Energy started by Kirk Sorensen who is the man featured in both of the documentaries posted in the OP.
They apparently have some military contracts to develop small modular LFTRs because under the current nuclear regulatory environment in the US it is easier to get unorthodox reactor designs approved for military use than it is for civilian use.
This is cool, but apparently thorium is ~3x as expensive as enriched uranium. That could be part of the reason why uranium is the preferred fuel for nuclear reactors.
On January 25 2012 11:18 SnipedSoul wrote: This is cool, but apparently thorium is ~3x as expensive as enriched uranium. That could be part of the reason why uranium is the preferred fuel for nuclear reactors.
Yes but as the article points out the high price of Throium is currently because it is not used for much, and if we started to build alot of LFTRs the price could drop to 10$/ton very quickly. There is a discussion in the "LFTR in 5 Minutes" video about how the fuel costs are essentially zero because Thorium is so abundant and is always being mined in rare earth mining operations, so the first several dozen kilotons of Thorium are already extracted and ready. In fact there is a really interesting part of the movie discussing how it would give the US an advantage over China in the rare earths market because it would make rare earth mining in the US much more profitable if thorium wasnt subject to all the unecessary regulations in the US. Thorium is currently treated as radioactive rock in the US and must be stored in nuclear disposal vessels, making it prohibitively expensive to mine rare earths in the US, since they are always found with Thorium. Thorium is not radioactive. It has a half-life of 14 billion years, as old as the universe, making it one of the most stable elements on earth. You can hold it in your hand or keep it in your pocket, it will not harm you.
Peter Schiff had some former NASA nuclear engineers on his show the other day, talking about LTFRs and their company. They're raising funds right now, and we'll have to see how it goes. I don't know much about the science but if NASA guys are putting their life on the line for it, it's gotta be promising.
They have thorium reactors in India too right? And there was one in Chernobyl too if I recall correctly.
I think it's a great and underused technology. Probably because it still bears the same stigmas traditional nuclear power does. After all it still produces some radiation, and you still need a bit of the weapons grade stuff to get it going.
On January 25 2012 11:59 EternaLLegacy wrote: Peter Schiff had some former NASA nuclear engineers on his show the other day, talking about LTFRs and their company. They're raising funds right now, and we'll have to see how it goes. I don't know much about the science but if NASA guys are putting their life on the line for it, it's gotta be promising.
That was Kirk Sorensen and Flibe Energy! Thanks for the heads up I had never heard it.
On January 25 2012 12:08 Tanukki wrote: They have thorium reactors in India too right? And there was one in Chernobyl too if I recall correctly.
I think it's a great and underused technology. Probably because it still bears the same stigmas traditional nuclear power does. After all it still produces some radiation, and you still need a bit of the weapons grade stuff to get it going.
dont put chernobyl's name next to anything good people will run away scared!
On January 25 2012 12:08 Tanukki wrote: They have thorium reactors in India too right? And there was one in Chernobyl too if I recall correctly.
I think it's a great and underused technology. Probably because it still bears the same stigmas traditional nuclear power does. After all it still produces some radiation, and you still need a bit of the weapons grade stuff to get it going.
The Thorium reactors in India are still solid-fuel reactors, so they are still Pressurized Water Reactors. They are Generation III, much safer than Fukushima Daichi which was a Generation I reactor, but LFTR is even safer than that.
Chernobyl I do not think is accurate, but I could be wrong. Definitely the one that melted down at Chernobyl was not a LFTR. But to Russia's credit, Russia is currently the only country to be successfully operating a LMFBR, which is the BN-600 reactor. But that only shows how incredibly difficult it is to operate an LMFBR.
Yes you need the "weapons grade stuff" but it is used as a seed at the very start of operation of the reactor, and then not needed again. U-235 (weapons grade) is currently used everyday all over the world as nuclear fuel because of our failure to adopt LFTR in the 1970s.
It's a decent idea but I'm not expecting to see any LFTR reactors anytime soon. After decades of nuclear mismanagment from the various industries public opinion isn't exactly at an all-time high, and this will be sold as modern nuclear power. Add to that the current nuclear industry is based on uranium, I would say they have a vested interest in not seeing any competition, and they don't have the money to be building an entire new industry. So discounting private start-up (who has the money?) or civil projects, as someone said above the military is the most likely way for thorium. Except you can't make a thorium bomb, so where is the incentive? Still, opposition to thorium will change as we exhaust other possibilities andd resources.
Question to the guy above who mentioned thorium is expensive now - surely economics says that prices are low if the market is flooded or if a product is undesirable. Making a demand for something drives up a price, so wouldn't the price of thorium remain very high? It wouldn't be in the interests of the industry to make too much thorium available...
On January 25 2012 12:49 Sanctimonius wrote: It's a decent idea but I'm not expecting to see any LFTR reactors anytime soon. After decades of nuclear mismanagment from the various industries public opinion isn't exactly at an all-time high, and this will be sold as modern nuclear power. Add to that the current nuclear industry is based on uranium, I would say they have a vested interest in not seeing any competition, and they don't have the money to be building an entire new industry. So discounting private start-up (who has the money?) or civil projects, as someone said above the military is the most likely way for thorium. Except you can't make a thorium bomb, so where is the incentive? Still, opposition to thorium will change as we exhaust other possibilities andd resources.
Question to the guy above who mentioned thorium is expensive now - surely economics says that prices are low if the market is flooded or if a product is undesirable. Making a demand for something drives up a price, so wouldn't the price of thorium remain very high? It wouldn't be in the interests of the industry to make too much thorium available...
It is impossible to limit the amount of thorium available, we already have too much. But Thorium does not obey the economic laws you quoted above because it is an ore and requires processing which is very expensive and if there isnt a market for it no one invests in the processing facilities and getting processed ore becomes very expensive.
The military are interested in LFTR for mobile modular power supplies that can power a base in the middle of the desert or other remote locations, not for bombs.
I would not characterize nuclear power as being decades of mismanagement, though I definitely would characterize Tepco as that. Nuclear power in the United States has never killed anyone, ever. Coal annually kills over 10,000 people. Annually!! So while you are right that public opinion is against nuclear, I wouldn't say decades of mismanagement is a fair characterization. Nuclear power actually has one of the safest track records of any industry, but public opinion reflects the opposite.
Not to say that it is not neat, but the problem with nuclear energy is not the manner of production, it's the general public (read: idiots) outlook on nuclear energy. We should have been on a mostly nuclear grid a while ago.
I read an interesting comment-conversation a few months back when they had an article about greenpeace guys breaking into a French nuclear facility.
"Well, what if they had gotten shot? It would have doubled the number of nuclear energy-related deaths in the last decade!"
I recommend that everyone listen to the Drunk Tank Podcast #43 LINK. They explain it really well. Also, the podcast is amazingly funny, but its about 2 years old so recognize that the information they talk about is outdated.
This is really interesting ,hooray for almost infinite green energy :D.
Of course there is a lot of investment on nuclear energy and its war potential so it will probably take a while for this to be truly a "mainstream" energy source.
On January 25 2012 12:56 WTFZerg wrote: It's a very, very old concept.
Not to say that it is not neat, but the problem with nuclear energy is not the manner of production, it's the general public (read: idiots) outlook on nuclear energy. We should have been on a mostly nuclear grid a while ago.
I read an interesting comment-conversation a few months back when they had an article about greenpeace guys breaking into a French nuclear facility.
"Well, what if they had gotten shot? It would have doubled the number of nuclear energy-related deaths in the last decade!"
it can not be put as simply as idioticy of masses. almost any form of invesment in nuclear enegry has a return of nuclear. Disagreement agains nuclear power is not foolish. its just simple.
If such technology would allow us to have nuclear energy without letting people develop weapons over it.. fine with me.
I always thought that the actual problem of old nuclear plants was the nuclear waste and not safety because I find it somewhat irresponsible to "produce" something that you can't really dispose of (storing it away for a long period of time is not really disposing).
Apparently that would be solved with these new reactors which, in my point of view, is the biggest advantage of this technology. How exactly do they burn up nuclear waste and why do points 4 & 5 seem somewhat contradictive (couldn't you just burn up the new waste?)
Just don't tell people their drinking water is being produced by a nuclear power plant <_<
Sounds cool though, There are such extraordinary amounts of energy in even small amounts of matter, finding a safe and efficient means of harvesting it seems like a great way to go.
On January 25 2012 10:32 EtherealDeath wrote: In a nutshell, if this was conceived of in the 1950s, why did they go and make all those PWRs?
Excellent question, and this is covered extensively in those two documentaries, but the short answer is that Thorium is useless for making a nuclear weapon, and in the 1950s at the height of the Cold War they wanted to generate power and make bombs, so they chose U-235 and the U-238-->Pu-239 fuel cycles, both of which can be used for electricity and for bombs.
This doesn't make much sense. For the US, sure. But tons of countries, all the countries in scandinavia for example, use nuclear fission power without any intention of making any weapons, Sweden hasn't had a nuclear weapon program since the early years of the cold war. Why are we not using thorium reactors here?
On January 25 2012 17:41 abalam wrote: I always thought that the actual problem of old nuclear plants was the nuclear waste and not safety because I find it somewhat irresponsible to "produce" something that you can't really dispose of (storing it away for a long period of time is not really disposing).
Apparently that would be solved with these new reactors which, in my point of view, is the biggest advantage of this technology. How exactly do they burn up nuclear waste and why do points 4 & 5 seem somewhat contradictive (couldn't you just burn up the new waste?)
I'd be glad if someone could answer my questions.
The key is understanding that nuclear waste is not waste. It would be better to call it "unspent fuel." 99% of it is simply broken up, brittle Uranium Oxide that is no good for use anymore in a solid fuel reactor. But it is still fissile, so it can be easily converted for use in a LFTR. And since LFTR uses liquid not solid fuels, the fuel stays in the reactor until it is used up. This is why LFTRs can burn up existing "nuclear waste" without generating any new waste of its own. In reality LFTRs do produce some actual nuclear waste, known as transuranics, but the amount produced over a decade is miniscule (as mentioned in the OP, a few millionths of a gram over ten years for a 40MW "mini" LFTR.)
On January 25 2012 10:32 EtherealDeath wrote: In a nutshell, if this was conceived of in the 1950s, why did they go and make all those PWRs?
Excellent question, and this is covered extensively in those two documentaries, but the short answer is that Thorium is useless for making a nuclear weapon, and in the 1950s at the height of the Cold War they wanted to generate power and make bombs, so they chose U-235 and the U-238-->Pu-239 fuel cycles, both of which can be used for electricity and for bombs.
This doesn't make much sense. For the US, sure. But tons of countries, all the countries in scandinavia for example, use nuclear fission power without any intention of making any weapons, Sweden hasn't had a nuclear weapon program since the early years of the cold war. Why are we not using thorium reactors here?
I don't know, it is an excellent question, since all Scandinavian countries have large Thorium deposits. Perhaps you should be calling your politicians in Sweden asking them why they never pursued this. Any moderately-sized developed country should be able to develop LFTR using their existing national resources.
Canada is one of the largest producers of uranium in the world, and I highly doubt the US would allow that to change without a fight. With so much money and investment into current new technology I doubt we'll see this change until it is absolutely necessary, and by that time we'll probably be fighting over the last remaining oil supplies.
The reason why PWRs dominated is because of their development in the US Navy's Submarine program. Rickover did all the leg work in developing the PWR (which is also inherently stable due to negative temperature coefficient of reactivity, btw), thus obviating the need for a secondary type of reactor.
When faced with the decision of spending millions in funding to test a new type of reactor with unproven results (the LFTR), or using a safe and proven technology, the decision for most governments was easy to make. It also helps that the PWR has a higher energy output per unit volume of reactor space compared to a LFTR (though this is mainly for ships I guess).
In regards to Chernobyl, it was a PWR, not a LFTR. The design was not inherently stable in the way most American PWRS are (this accident could never happen on a Navy nuke anyway), but it was not particularly unsafe either. The accident was due to a safety test which involved trying to shut down the reactor under some worst case conditions. The test was an egregious violation of all reason in a nuclear plant, which lead to the catastrophe.
The only thing they would have to do is scaring the populace, something we are pretty good at, that China will be in a monopoly on energy because they have all the thorium and heavy metals and they will abuse that power to question our freedom. Done. Readily factured for the American media propaganda that will probably work on Fox news.
Of course, doing so would require oil companies to reinvest into a technology that would gain them less money because the cost for energy would go down. So obviously they will invest into energy that is even less efficient but more 'green' so they can price it even more.
I see this as a pretty logical approach to why major energy companies would work like this if what they said was true. The only problem is if your energy is obsolete while anothers is better, there will be a struggle with the old and the new. Unfortunately the old and the new in this case are the US and China. Now I'm pretty glad the Cold war has ended and I don't really want another one in my lifetime.
In any case, I will look up to the first that proves that this is possible.
On January 25 2012 22:45 GeneralStan wrote: The reason why PWRs dominated is because of their development in the US Navy's Submarine program. Rickover did all the leg work in developing the PWR (which is also inherently stable due to negative temperature coefficient of reactivity, btw), thus obviating the need for a secondary type of reactor.
When faced with the decision of spending millions in funding to test a new type of reactor with unproven results (the LFTR), or using a safe and proven technology, the decision for most governments was easy to make. It also helps that the PWR has a higher energy output per unit volume of reactor space compared to a LFTR (though this is mainly for ships I guess).
As Kirk Sorensen details in the movie, Alvin Weinberg, who was instrumental in the invention of the PWR and BWR, did not like either design due to safety concerns and the solid fuel aspect and was pushing LFTR. The U-235 and Pu-239 fuel cycles were better understood than Thorium, no question. But Weinberg with the MSRE did prove the viability and safety of the concept, and in the 1960s it was expected by many that PWRs would not last very long because they would be replaced by better technologies like LFTR. The reason this did not happen is primarily due to Cold War considerations. You can't make nuclear bombs with a LFTR, just electricity. With PWRs or LMFBRs you can do both, so that is why both the US and the USSR pursued those technologies.
Yes PWRs do have a negative temperature coefficient of reactivity, but they are by no means walk away safe as a LFTR is. On top of constantly worrying about pipe shears, pressure drops and meltdowns, none of which are possible in a LFTR but are entirely possible in a PWR, you also have to constantly monitor Xenon-135 levels in a PWR, since in solid fuel reactors the Xenon-135 stays in the fuel and as a neutron absorber causes a lot of problems in your reactor. In a LFTR since the fuel is a liquid the Xenon-135 just bubbles right out of the solution. This is yet another of the many safety advantages LFTR has over PWRs. PWRs are ready to explode, begging to explode even. LFTRs can never explode.
On January 25 2012 22:45 GeneralStan wrote: It also helps that the PWR has a higher energy output per unit volume of reactor space compared to a LFTR (though this is mainly for ships I guess).
This doesn't make any sense. On land the reactors would be smaller, the amount of nuclear material would be smaller, and the amount of energy would be greater than that of the current method. Why would it be any different on a ship?
On January 25 2012 22:45 GeneralStan wrote: The reason why PWRs dominated is because of their development in the US Navy's Submarine program. Rickover did all the leg work in developing the PWR (which is also inherently stable due to negative temperature coefficient of reactivity, btw), thus obviating the need for a secondary type of reactor.
When faced with the decision of spending millions in funding to test a new type of reactor with unproven results (the LFTR), or using a safe and proven technology, the decision for most governments was easy to make. It also helps that the PWR has a higher energy output per unit volume of reactor space compared to a LFTR (though this is mainly for ships I guess).
As Kirk Sorensen details in the movie, Alvin Weinberg, who was instrumental in the invention of the PWR and BWR, did not like either design due to safety concerns and the solid fuel aspect and was pushing LFTR. The U-235 and Pu-239 fuel cycles were better understood than Thorium, no question. But Weinberg with the MSRE did prove the viability and safety of the concept, and in the 1960s it was expected by many that PWRs would not last very long because they would be replaced by better technologies like LFTR. The reason this did not happen is primarily due to Cold War considerations. You can't make nuclear bombs with a LFTR, just electricity. With PWRs or LMFBRs you can do both, so that is why both the US and the USSR pursued those technologies.
Yes PWRs do have a negative temperature coefficient of reactivity, but they are by no means walk away safe as a LFTR is. On top of constantly worrying about pipe shears, pressure drops and meltdowns, none of which are possible in a LFTR but are entirely possible in a PWR, you also have to constantly monitor Xenon-135 levels in a PWR, since in solid fuel reactors the Xenon-135 stays in the fuel and as a neutron absorber causes a lot of problems in your reactor. In a LFTR since the fuel is a liquid the Xenon-135 just bubbles right out of the solution. This is yet another of the many safety advantages LFTR has over PWRs. PWRs are ready to explode, begging to explode even. LFTRs can never explode.
As far as I know, the more modern pebble-bed reactor design is virtually meltdown proof, but I'm not sure if that design is utilized in any modern reactor.
On January 25 2012 10:51 Perdac Curall wrote: matter-antimatter annihilation sometime after that.
How would that even work? Unless you have a supply of antimatter (which we do not), it will take more energy to create the fuel than we get out of it.
It's useful for interstellar propulsion because it has the lowest mass per unit energy output of any fuel, but not as an energy source.
There was a meeting back in 2004 on this very subject detailing the need for a dedicated antiproton facility in the US, but it was ignored by the Bush administration. The amount of energy in matter-antimatter reactions is 1000 times as energy dense as fusion, so it is not implausible that we can achieve a net energy gain there in the future (50-75 years from now when commercial fusion reactors are (hopefully) a reality.)
On January 25 2012 22:45 GeneralStan wrote: The reason why PWRs dominated is because of their development in the US Navy's Submarine program. Rickover did all the leg work in developing the PWR (which is also inherently stable due to negative temperature coefficient of reactivity, btw), thus obviating the need for a secondary type of reactor.
When faced with the decision of spending millions in funding to test a new type of reactor with unproven results (the LFTR), or using a safe and proven technology, the decision for most governments was easy to make. It also helps that the PWR has a higher energy output per unit volume of reactor space compared to a LFTR (though this is mainly for ships I guess).
As Kirk Sorensen details in the movie, Alvin Weinberg, who was instrumental in the invention of the PWR and BWR, did not like either design due to safety concerns and the solid fuel aspect and was pushing LFTR. The U-235 and Pu-239 fuel cycles were better understood than Thorium, no question. But Weinberg with the MSRE did prove the viability and safety of the concept, and in the 1960s it was expected by many that PWRs would not last very long because they would be replaced by better technologies like LFTR. The reason this did not happen is primarily due to Cold War considerations. You can't make nuclear bombs with a LFTR, just electricity. With PWRs or LMFBRs you can do both, so that is why both the US and the USSR pursued those technologies.
Yes PWRs do have a negative temperature coefficient of reactivity, but they are by no means walk away safe as a LFTR is. On top of constantly worrying about pipe shears, pressure drops and meltdowns, none of which are possible in a LFTR but are entirely possible in a PWR, you also have to constantly monitor Xenon-135 levels in a PWR, since in solid fuel reactors the Xenon-135 stays in the fuel and as a neutron absorber causes a lot of problems in your reactor. In a LFTR since the fuel is a liquid the Xenon-135 just bubbles right out of the solution. This is yet another of the many safety advantages LFTR has over PWRs. PWRs are ready to explode, begging to explode even. LFTRs can never explode.
As far as I know, the more modern pebble-bed reactor design is virtually meltdown proof, but I'm not sure if that design is utilized in any modern reactor.
UC Berkeley and Oak Ridge are working on a pebble-bed fluoride salt high temperature reactor right now. And yes you are right pebble-bed technology is very safe, being Generation IV technology, but I still believe LFTR is an even better idea. Here is a short video presentation done at the last Thorium Energy Alliance Conference (TEAC3) done by a doctoral student at UC Berkeley explaining the details of the reactor design.
On January 25 2012 12:49 Sanctimonius wrote: It's a decent idea but I'm not expecting to see any LFTR reactors anytime soon. After decades of nuclear mismanagment from the various industries public opinion isn't exactly at an all-time high, and this will be sold as modern nuclear power. Add to that the current nuclear industry is based on uranium, I would say they have a vested interest in not seeing any competition, and they don't have the money to be building an entire new industry. So discounting private start-up (who has the money?) or civil projects, as someone said above the military is the most likely way for thorium. Except you can't make a thorium bomb, so where is the incentive? Still, opposition to thorium will change as we exhaust other possibilities andd resources.
Question to the guy above who mentioned thorium is expensive now - surely economics says that prices are low if the market is flooded or if a product is undesirable. Making a demand for something drives up a price, so wouldn't the price of thorium remain very high? It wouldn't be in the interests of the industry to make too much thorium available...
It is impossible to limit the amount of thorium available, we already have too much. But Thorium does not obey the economic laws you quoted above because it is an ore and requires processing which is very expensive and if there isnt a market for it no one invests in the processing facilities and getting processed ore becomes very expensive.
The military are interested in LFTR for mobile modular power supplies that can power a base in the middle of the desert or other remote locations, not for bombs.
I would not characterize nuclear power as being decades of mismanagement, though I definitely would characterize Tepco as that. Nuclear power in the United States has never killed anyone, ever. Coal annually kills over 10,000 people. Annually!! So while you are right that public opinion is against nuclear, I wouldn't say decades of mismanagement is a fair characterization. Nuclear power actually has one of the safest track records of any industry, but public opinion reflects the opposite.
Tepco is just the latest and most obvious example of nuclear mismanagement. Nuclear power stations across the world have in numerous cases been found to have low-level leaks and failing safety systems, but discounting those what about the more well-known leaks - Three Mile, Chernobyl etc. Spread over decades. Mismanaged
Thing is it doesn't matter what is a fair characterisation when it comes to public opinion. Public opinion is very strongly against nuclear power, regardless of the safety record of the industry. You can show the figures to people but we always have that fear of nuclear meltdown in our minds.
I've been very interested in Thorium reactor fuels ever since I heard of them about a year ago. It has always sounded like a miracle fuel as such I've been very sceptical of the claims around it. But I have yet to see anything truly negative in comparison to other technologies out there. This looks and feels right now like the energy technology that will be heavily invested in within the coming years (perhaps a decade). I truly hope there's not some catch 22 because clean, cheap and abundant energy sources would solve so many of the worlds current problems.
I read something about Pebble Bed Reactors in a magizine (Time?) while waiting for my turn at the orthodontist. The concept seems much safer than normal rod-fueled plants. Here's a link: http://en.wikipedia.org/wiki/Pebble_bed_reactor
On January 25 2012 12:49 Sanctimonius wrote: It's a decent idea but I'm not expecting to see any LFTR reactors anytime soon. After decades of nuclear mismanagment from the various industries public opinion isn't exactly at an all-time high, and this will be sold as modern nuclear power. Add to that the current nuclear industry is based on uranium, I would say they have a vested interest in not seeing any competition, and they don't have the money to be building an entire new industry. So discounting private start-up (who has the money?) or civil projects, as someone said above the military is the most likely way for thorium. Except you can't make a thorium bomb, so where is the incentive? Still, opposition to thorium will change as we exhaust other possibilities andd resources.
Question to the guy above who mentioned thorium is expensive now - surely economics says that prices are low if the market is flooded or if a product is undesirable. Making a demand for something drives up a price, so wouldn't the price of thorium remain very high? It wouldn't be in the interests of the industry to make too much thorium available...
It is impossible to limit the amount of thorium available, we already have too much. But Thorium does not obey the economic laws you quoted above because it is an ore and requires processing which is very expensive and if there isnt a market for it no one invests in the processing facilities and getting processed ore becomes very expensive.
The military are interested in LFTR for mobile modular power supplies that can power a base in the middle of the desert or other remote locations, not for bombs.
I would not characterize nuclear power as being decades of mismanagement, though I definitely would characterize Tepco as that. Nuclear power in the United States has never killed anyone, ever. Coal annually kills over 10,000 people. Annually!! So while you are right that public opinion is against nuclear, I wouldn't say decades of mismanagement is a fair characterization. Nuclear power actually has one of the safest track records of any industry, but public opinion reflects the opposite.
Tepco is just the latest and most obvious example of nuclear mismanagement. Nuclear power stations across the world have in numerous cases been found to have low-level leaks and failing safety systems, but discounting those what about the more well-known leaks - Three Mile, Chernobyl etc. Spread over decades. Mismanaged
Thing is it doesn't matter what is a fair characterisation when it comes to public opinion. Public opinion is very strongly against nuclear power, regardless of the safety record of the industry. You can show the figures to people but we always have that fear of nuclear meltdown in our minds.
Chernobyl was absolutely bad in every way. Bad design, bad management, a clusterfuck. And people should be concerned about meltdowns and safety with PWRs. Eugene Wigner, who invented the PWR, was against PWRs because it was only a matter of time before an accident occurs with water held at that much pressure. That is why Wigner was such a huge advocate for LFTR for civilian power, because it is so much safer. People would not have to worry about meltdowns anymore if we transitioned to LFTRs.
Got interested by the article and read up on it. Definitly intrieged me, but one thing caught my eye on wikipedia.
After shutdown the salt was believed to be in long-term safe storage, but beginning in the mid-1980s, there was concern that radioactivity was migrating through the system. Sampling in 1994 revealed concentrations of uranium that created a potential for a nuclear criticality accident, as well as a potentially dangerous build-up of fluorine gas — the environment above the solidified salt is approximately one atmosphere of fluorine. The ensuing decontamination and decommissioning project was called "the most technically challenging" activity assigned to Bechtel Jacobs under its environmental management contract with the U.S. Department of Energy's Oak Ridge Operations organization. In 2003, the MSRE cleanup project was estimated at about $130 million, with decommissioning expected to be completed in 2009.[17]
A detailed description of potential decommissioning processes is described here.18] uranium is to be removed from the fuel as the hexafluoride by adding excess fluorine, and plutonium as the plutonium dioxide by adding sodium carbonate.
On January 27 2012 12:10 Dynastywar wrote: Got interested by the article and read up on it. Definitly intrieged me, but one thing caught my eye on wikipedia.
After shutdown the salt was believed to be in long-term safe storage, but beginning in the mid-1980s, there was concern that radioactivity was migrating through the system. Sampling in 1994 revealed concentrations of uranium that created a potential for a nuclear criticality accident, as well as a potentially dangerous build-up of fluorine gas — the environment above the solidified salt is approximately one atmosphere of fluorine. The ensuing decontamination and decommissioning project was called "the most technically challenging" activity assigned to Bechtel Jacobs under its environmental management contract with the U.S. Department of Energy's Oak Ridge Operations organization. In 2003, the MSRE cleanup project was estimated at about $130 million, with decommissioning expected to be completed in 2009.[17]
A detailed description of potential decommissioning processes is described here.18] uranium is to be removed from the fuel as the hexafluoride by adding excess fluorine, and plutonium as the plutonium dioxide by adding sodium carbonate.
There are a few known technical challenges left to master with LFTR, and this is one of the biggest. However in the grand scale of things engineering-wise this is not that difficult of problem to overcome. This is basically a storage and containment problem. When compared to the technical hurdles still facing other reactor designs such as Fusion reactors, Integral Fast Reactors or the Travelling Wave reactor that Bill Gates is so keen on funding, the challenges associated with LFTR are almost "easy" relative to them.
I heard of the LFTR a few days ago in this thread.
Conclusion I made so far:
Even though it really looks promising, I think humans need to to take nuclear energy way more seriously (even LFTR). I still don't understand how can we use nuclear energy as of now with the current problems radioactive waste presentes, right now we don't have the understanding in science to treat and handle this substances correctly to ensure the well-beeing of the generations of livings things to come.
I do think LFTR still have many challenges before dreaming of implementation.
And finally LFTR does produce radiactive waste just in smaller quantity and faster radioctive decay (this means that the radioctive element desactivates faster)
Although it really looks promising, but let's see only a lot of research and time will tell.
PS.: We only have one earth it really worries me, that we are directioning to our auto-anihilation by the hazardous subproducts of our current technology (i.e. contamination) and the unforgiving exploitation of our resources.
I think it's a responsability of this generations technic and scientific professionals to stop and prevent this madness and improve the current human process for the better of ourselves and our planet.
I'm surprised that the United States haven't already restarted investing into this technology since the Soviet Union collapsed. Maybe it had something to do with political pressure?
On January 27 2012 13:13 Roe wrote: isn't thorium just some mineral from world of warcraft?
Yes, that's why this new technology is being developed in China. All of their gold farmers have built up a large surplus over the time that WoW has been out, and now they're making use of it to generate power.
Of course, doing so would require oil companies to reinvest into a technology that would gain them less money because the cost for energy would go down. So obviously they will invest into energy that is even less efficient but more 'green' so they can price it even more.
You made it sound like the whole world's energy is generated by 1 company. If a company is able to come up a super efficient and green energy, it will dominate the market, earning way more money.
Yeah thanks for this thread I recently watched a Google Tech Talk on this but the Thorium Remix doco was great to see. At first I was skeptical but it seems legitimate (at least with my limited understanding of the science).
I guess the main issue is that someone has to be the first to pioneer the full-scale reactor. I am annoyed that Australia hasn't done more in the area (since according to some sources we have the largest Thorium reserves in the world). Either way once China has a successful reactor underway the argument for it will be much stronger. Especially if the environmental advantages can be quantitatively illustrated.
On January 25 2012 10:27 Perdac Curall wrote: 4) LFTRs do not produce the "spent fuel" problem of ordinary solid fuel reactors like PWRs. Because the fuel is a liquid it can be fully burnt up in the reactor, so storage of spent fuel is not necessary.
Something seems fishy with the neutron economy here. Normal nuclear fuel has to be replaced because some fission products are neutron absorbers and when more neutrons are absorbed than produced you lose criticality. Thorium is already a neutron down versus U-235. It has to undergo a neutron capture then decay to U-233 before it is fissile. (similar to the U-238 -> Pu-239 path)
Furthermore the projected transuranic waste of a 40MW "mini" reactor produced over ten years is anticipated to be only a few millionths of a gram. This is teeny tiny amounts of pollution.
That seem a very odd way to say that the reactor won't make any plutonium. There are still plenty of nasty products below 92.
9) unlike LMFBRs it does not use fast neutrons, it uses thermal neutrons, which makes fission much easier to achieve
It needs thermal neutrons because thermal neutrons make fission easier to achieve, not because thermal neutrons are easier to produce. Fission produces fast neutrons, which turn into thermal neutrons as they slow down through collisions with a moderator.
On January 26 2012 03:06 Perdac Curall wrote: The amount of energy in matter-antimatter reactions is 1000 times as energy dense as fusion, so it is not implausible that we can achieve a net energy gain there in the future
It is implausible that energy wouldn't be conserved. It takes more energy to produce antimatter then you get from its annihilation. At best you would break even, but that'd need a world without thermodynamics.
On January 25 2012 10:27 Perdac Curall wrote: 4) LFTRs do not produce the "spent fuel" problem of ordinary solid fuel reactors like PWRs. Because the fuel is a liquid it can be fully burnt up in the reactor, so storage of spent fuel is not necessary.
Something seems fishy with the neutron economy here. Normal nuclear fuel has to be replaced because some fission products are neutron absorbers and when more neutrons are absorbed than produced you lose criticality. Thorium is already a neutron down versus U-235. It has to undergo a neutron capture then decay to U-233 before it is fissile. (similar to the U-238 -> Pu-239 path)
Furthermore the projected transuranic waste of a 40MW "mini" reactor produced over ten years is anticipated to be only a few millionths of a gram. This is teeny tiny amounts of pollution.
That seem a very odd way to say that the reactor won't make any plutonium. There are still plenty of nasty products below 92.
9) unlike LMFBRs it does not use fast neutrons, it uses thermal neutrons, which makes fission much easier to achieve
It needs thermal neutrons because thermal neutrons make fission easier to achieve, not because thermal neutrons are easier to produce. Fission produces fast neutrons, which turn into thermal neutrons as they slow down through collisions with a moderator.
The fission of Uranium-233 produces on average 2.5 neutrons per fission, so it is above the required threshold of 2. Furthermore the worst neutron absorber, Xe-135, which is such a nuisance is solid fuel reactors, is not a problem at all in a LFTR, since it is a gas and just bubbles out of the liquid fuel.
Here is a great talk by Kirk Sorensen on so-called "nuclear waste," most of which is just as valuable as the electricity produced.
Yes thermal neutrons make fission easier to achieve, that is what was said in the post you quoted. The neutron cross-sections involved with thermal neutrons are so much bigger than with fast neutrons.
You are correct there are no control rods anticipated in the LFTR. Last I heard they were anticipating circulating graphite spheres in with the liquid fuel as a neutron moderator. Also that's a great graphic thanks alot I had not seen it before.
I will leave this thread with a wealth of knowledge on the subject, great post, and great replys OP, really informative and has changed my opinion of Nuclear power in general, I would love to see energy technology adopt LFTR - it seems much more stable, abundant, efficient and cleaner.
On January 28 2012 16:08 v3chr0 wrote: I will leave this thread with a wealth of knowledge on the subject, great post, and great replys OP, really informative and has changed my opinion of Nuclear power in general, I would love to see energy technology adopt LFTR - it seems much more stable, abundant, efficient and cleaner.
Comments like that make it all worthwhile. LFTR certainly caused me to re-examine my opinion on nuclear fission as well.
On January 25 2012 10:51 Perdac Curall wrote: matter-antimatter annihilation sometime after that.
How would that even work? Unless you have a supply of antimatter (which we do not), it will take more energy to create the fuel than we get out of it.
It's useful for interstellar propulsion because it has the lowest mass per unit energy output of any fuel, but not as an energy source.
There was a meeting back in 2004 on this very subject detailing the need for a dedicated antiproton facility in the US, but it was ignored by the Bush administration. The amount of energy in matter-antimatter reactions is 1000 times as energy dense as fusion, so it is not implausible that we can achieve a net energy gain there in the future (50-75 years from now when commercial fusion reactors are (hopefully) a reality.)
Yes, the 1000 times as energy dense is what lends it to being such an attractive idea for space travel as it saves so much weight. But it does not suggest that we could achieve a net energy gain. Fact is, because we do not have an antimatter mine anywhere we would have to make it ourselves. And due to the nature of matter-antimatter annihilation the best case scenario is that we get the same amount of energy out as we put in to make it, which isn't such an attractive property for a fuel.
It is a commercially manufactured salt combination of Beryllium Fluoride and Lithium Fluoride. Flibe Energy, which is the only US company I know of pursuing LFTR, is named after it.
On January 25 2012 10:51 Perdac Curall wrote: matter-antimatter annihilation sometime after that.
How would that even work? Unless you have a supply of antimatter (which we do not), it will take more energy to create the fuel than we get out of it.
It's useful for interstellar propulsion because it has the lowest mass per unit energy output of any fuel, but not as an energy source.
There was a meeting back in 2004 on this very subject detailing the need for a dedicated antiproton facility in the US, but it was ignored by the Bush administration. The amount of energy in matter-antimatter reactions is 1000 times as energy dense as fusion, so it is not implausible that we can achieve a net energy gain there in the future (50-75 years from now when commercial fusion reactors are (hopefully) a reality.)
Yes, the 1000 times as energy dense is what lends it to being such an attractive idea for space travel as it saves so much weight. But it does not suggest that we could achieve a net energy gain. Fact is, because we do not have an antimatter mine anywhere we would have to make it ourselves. And due to the nature of matter-antimatter annihilation the best case scenario is that we get the same amount of energy out as we put in to make it, which isn't such an attractive property for a fuel.
You may be right, but in 50-75 years I hope mankind can prove you wrong.
After reading up on this it seems that the fuel would be absolutely vile. As in if you get a leak people will die because you need heavy shielding to work with it and it fries electronics so remote manipulation gets harder.
Seems like a decent idea but remember that toxic liquid fuels almost always get replaced with solid fuels because handling and maintnance never work out well. Simply put fluids leak and toxic leaks are bad.
It does look like another too good to be true story but if it is really a viable method for nuclear energy, why the hell isn't the US government actively pursing the technology? Because mastering this would basically solve our entire energy problem. That the US government would pass this over and let china go after it alone would mean that we really have total dumbasses heading this country.
On January 28 2012 20:00 white_horse wrote: Cool read, thanks.
It does look like another too good to be true story but if it is really a viable method for nuclear energy, why the hell isn't the US government actively pursing the technology? Because mastering this would basically solve our entire energy problem. That the US government would pass this over and let china go after it alone would mean that we really have total dumbasses heading this country.
German government then would be even more stupid since we waste a lot of money on solar energy subsidies. But people here freak out when they hear "nuclear power".
On January 28 2012 21:26 enemy2010 wrote: Two words: renewable energies.
I study energy ecomonics, and I personally thing this is the only way.
Would you mind sharing your elaborate thoughts with us? Personally I prefer extreme efficiency over 'renewable' that is even more inefficient than oil, like solar or wind.
Either you build one nuclear plant with a passive safety, or you build hundreds of windmills that will have to be forged out of steel that start off with a pretty big polution, and only after a very long time get any sort of gain out of it. Those windmills take up so much space that forests would have to be cut, houses need to be flattened and you will see so many of them that you basically become green of nausia.
On January 28 2012 21:26 enemy2010 wrote: Two words: renewable energies.
I study energy ecomonics, and I personally thing this is the only way.
Would you mind sharing your elaborate thoughts with us? Personally I prefer extreme efficiency over 'renewable' that is even more inefficient than oil, like solar or wind.
Either you build one nuclear plant with a passive safety, or you build hundreds of windmills that will have to be forged out of steel that start off with a pretty big polution, and only after a very long time get any sort of gain out of it. Those windmills take up so much space that forests would have to be cut, houses need to be flattened and you will see so many of them that you basically become green of nausia.
But I'd like to hear your thoughts on it.
Nuclear fusion is also being worked on and is expected to have a commercial prototype at around 2020-2030 iirc. I really don't get why people pursue renewable energies so much when clean nuclear energy is a much better alternative. There's enough fuel for nuclear fusion to last us millions of years (hint: it's everywhere in the oceans ^_^).
I believe research money is much better spent on research like these clean nuclear fission reactors or even better, nuclear fusion.
On January 28 2012 19:46 CuddlyCuteKitten wrote: After reading up on this it seems that the fuel would be absolutely vile. As in if you get a leak people will die because you need heavy shielding to work with it and it fries electronics so remote manipulation gets harder.
Seems like a decent idea but remember that toxic liquid fuels almost always get replaced with solid fuels because handling and maintnance never work out well. Simply put fluids leak and toxic leaks are bad.
The fuel doesn't fry electronics. If you put the U-233 in storage in a bomb it will fry the electronics of the bomb because it will start to decay and it has a hard gamma emitter in its decay chain. But if you use it as fuel you fission it before it ever has a chance to do this.
Handling and maintenance is actually much harder with solid fuels in a nuclear reactor. This is why we have this spent fuel problem currently in the nuclear industry. Eventually the solid fuel becomes brittle and broken up and we have to take it out of the reactor, and we only use less than 1% of its total energy. If we went over to LFTR and liquid fuels, all the fuel gets used up in the reactor, so handling and maintenance are actually much easier in a LFTR. You need much less shielding and a smaller containment wall with a LFTR because it doesn't operate at high pressure and there is no chance of a meltdown.
On January 28 2012 20:00 white_horse wrote: Cool read, thanks.
It does look like another too good to be true story but if it is really a viable method for nuclear energy, why the hell isn't the US government actively pursing the technology? Because mastering this would basically solve our entire energy problem. That the US government would pass this over and let china go after it alone would mean that we really have total dumbasses heading this country.
The US government did originally develop this technology, at Oak Ridge National Laboratory. But they cancelled the program despite all the promise it showed because, as you said, we have total dumbasses running the country.
On January 28 2012 19:46 CuddlyCuteKitten wrote: After reading up on this it seems that the fuel would be absolutely vile. As in if you get a leak people will die because you need heavy shielding to work with it and it fries electronics so remote manipulation gets harder.
Seems like a decent idea but remember that toxic liquid fuels almost always get replaced with solid fuels because handling and maintnance never work out well. Simply put fluids leak and toxic leaks are bad.
The fuel doesn't fry electronics. If you put the U-233 in storage in a bomb it will fry the electronics of the bomb because it will start to decay and it has a hard gamma emitter in its decay chain. But if you use it as fuel you fission it before it ever has a chance to do this.
Handling and maintenance is actually much harder with solid fuels in a nuclear reactor. This is why we have this spent fuel problem currently in the nuclear industry. Eventually the solid fuel becomes brittle and broken up and we have to take it out of the reactor, and we only use less than 1% of its total energy. If we went over to LFTR and liquid fuels, all the fuel gets used up in the reactor, so handling and maintenance are actually much easier in a LFTR. You need much less shielding and a smaller containment wall with a LFTR because it doesn't operate at high pressure and there is no chance of a meltdown.
Yes but what happens in case of a leak? Meltdown is not the only problem in a nuclear plant. Look at fukushima, no meltdown but still a major operation to fix, mostly inolving humans. But what if there was u232 in the leaked material, how do you fix it then?
Risk is reduced with lower pressure but equipment will fail and I can see it becoming a bitch to fix if the reaction stops and you have unreacted uranium left with hard gamma rays. Just like liquid fuel for icbms, to much of a hazard to maintain and dangerous to reapair if damaged.
On January 28 2012 19:46 CuddlyCuteKitten wrote: After reading up on this it seems that the fuel would be absolutely vile. As in if you get a leak people will die because you need heavy shielding to work with it and it fries electronics so remote manipulation gets harder.
Seems like a decent idea but remember that toxic liquid fuels almost always get replaced with solid fuels because handling and maintnance never work out well. Simply put fluids leak and toxic leaks are bad.
The fuel doesn't fry electronics. If you put the U-233 in storage in a bomb it will fry the electronics of the bomb because it will start to decay and it has a hard gamma emitter in its decay chain. But if you use it as fuel you fission it before it ever has a chance to do this.
Handling and maintenance is actually much harder with solid fuels in a nuclear reactor. This is why we have this spent fuel problem currently in the nuclear industry. Eventually the solid fuel becomes brittle and broken up and we have to take it out of the reactor, and we only use less than 1% of its total energy. If we went over to LFTR and liquid fuels, all the fuel gets used up in the reactor, so handling and maintenance are actually much easier in a LFTR. You need much less shielding and a smaller containment wall with a LFTR because it doesn't operate at high pressure and there is no chance of a meltdown.
Yes but what happens in case of a leak? Meltdown is not the only problem in a nuclear plant. Look at fukushima, no meltdown but still a major operation to fix, mostly inolving humans. But what if there was u232 in the leaked material, how do you fix it then?
Risk is reduced with lower pressure but equipment will fail and I can see it becoming a bitch to fix if the reaction stops and you have unreacted uranium left with hard gamma rays. Just like liquid fuel for icbms, to much of a hazard to maintain and dangerous to reapair if damaged.
If you have a leak it is a problem, you have to shut down the reactor for repairs. However there is no danger to the public, and those of us willing to work in the nuclear power industry accept these risks as part of the job. But again, there is no risk to the public or of environmental contamination, since it is not kept under extreme pressures. There isn't much of a risk of U-232 being in the leaked material, since U-233 is fissioned almost as soon as it is created in a LFTR. But if it ever did happen you would put on a shielding suit, clean it up and put it in a containment barrel.
On January 28 2012 21:26 enemy2010 wrote: Two words: renewable energies.
I study energy ecomonics, and I personally thing this is the only way.
But do you think that for instance due to major technological development in the future, renewable energy sources will be able to supply us with enough juice in scenarios where world energy demand increases exponentially? Is it really economically feasible in the long run? (talking about 50-100 years in the future)
On January 28 2012 21:26 enemy2010 wrote: Two words: renewable energies.
I study energy ecomonics, and I personally thing this is the only way.
But do you think that for instance due to major technological development in the future, renewable energy sources will be able to supply us with enough juice in scenarios where world energy demand increases exponentially? Is it really economically feasible in the long run? (talking about 50-100 years in the future)
You are absolutely right Bartuc they cannot supply us with enough juice. I used to be the biggest fan of solar until I actually crunched the numbers. There is no question there are a ton of applications for solar. Eventually all our cell phones will probably have a solar panel for instance. But those who say it can replace coal, oil, gas and nuclear for grid level generation simply haven't run the numbers. Solar panels, even at 100% efficiency, which we are a long way from, still do not even have the same energy density as coal, and are only slightly better than wood. In most places on Earth the sun provides less than 1500W/sq.m. and that is only for 8 hours a day, so you need a whole other energy generation grid in place for when the sun isnt shining. This just isnt feasible. The only hope for mankind is to move to denser energy sources like fission and fusion, not less dense and less efficient energy sources like wind and solar.
LFTRs and Pebble-bed style reactors have a huge potential to provide safer and cleaner nuclear energy. Considering that even though nuclear technology is fairly safe, there have been some major contamination events in history, and the recent Fukushima disaster has made the idea of nuclear power even more unpopular. It's a hard thing to sell to a group of aging and paranoid 50-70 year olds that retain a stigma towards nuclear topics in general. I hope that in the future these become a more viable option for power but like I said, a lot of people are generally paranoid about nuclear energy in general.
On January 25 2012 10:51 Perdac Curall wrote: matter-antimatter annihilation sometime after that.
How would that even work? Unless you have a supply of antimatter (which we do not), it will take more energy to create the fuel than we get out of it.
It's useful for interstellar propulsion because it has the lowest mass per unit energy output of any fuel, but not as an energy source.
There was a meeting back in 2004 on this very subject detailing the need for a dedicated antiproton facility in the US, but it was ignored by the Bush administration. The amount of energy in matter-antimatter reactions is 1000 times as energy dense as fusion, so it is not implausible that we can achieve a net energy gain there in the future (50-75 years from now when commercial fusion reactors are (hopefully) a reality.)
Yes, the 1000 times as energy dense is what lends it to being such an attractive idea for space travel as it saves so much weight. But it does not suggest that we could achieve a net energy gain. Fact is, because we do not have an antimatter mine anywhere we would have to make it ourselves. And due to the nature of matter-antimatter annihilation the best case scenario is that we get the same amount of energy out as we put in to make it, which isn't such an attractive property for a fuel.
You may be right, but in 50-75 years I hope mankind can prove you wrong.
You mean you hope in 50-75 years we prove the laws of thermodynamics wrong.... that would be really neat, but I'm not going to bet on it.
As for non perpetual motion machines providing long term energy. This sounds promising
Solar would only be useful if it was solar panels in space (they and putting them in space would have to be Much cheaper.. but there is plenty of space there)
Fusion would be more likely as a long term (of course it might be 30 years away for the next 500 years)
Holy shit watching that documentary was completely worth the 2 hours. I can't believe something like this was figured out and not taken advantage of immediately. And I got a pretty good science lesson out of it.
Renewable sources of energy are great and all, but the power being generated is not dependable since it is environmentally dependent. I am convinced that various forms of nuclear are the only way to go for the future.
What is most exciting for me about nuclear is that it has to capability to be used in space. Properly harnessing nuclear power is the path that will allow us to explore the final frontier.
On January 29 2012 09:03 RifleCow wrote: Renewable sources of energy are great and all, but the power being generated is not dependable since it is environmentally dependent. I am convinced that various forms of nuclear are the only way to go for the future.
What is most exciting for me about nuclear is that it has to capability to be used in space. Properly harnessing nuclear power is the path that will allow us to explore the final frontier.
I could not agree with you more. The idea of a manned mission to Mars with fusion powered rockets really gets me excited.
On January 29 2012 08:50 Attican wrote: Holy shit watching that documentary was completely worth the 2 hours. I can't believe something like this was figured out and not taken advantage of immediately. And I got a pretty good science lesson out of it.
It really is good and if you look through Gordon McDowell's youtube page there is a whole bunch more videos he has on there with great talks from some really brilliant people all about Thorium and LFTR. I'm not ashamed to admit I've seen that doc more than 5 times now
On January 25 2012 10:51 Perdac Curall wrote: matter-antimatter annihilation sometime after that.
How would that even work? Unless you have a supply of antimatter (which we do not), it will take more energy to create the fuel than we get out of it.
It's useful for interstellar propulsion because it has the lowest mass per unit energy output of any fuel, but not as an energy source.
There was a meeting back in 2004 on this very subject detailing the need for a dedicated antiproton facility in the US, but it was ignored by the Bush administration. The amount of energy in matter-antimatter reactions is 1000 times as energy dense as fusion, so it is not implausible that we can achieve a net energy gain there in the future (50-75 years from now when commercial fusion reactors are (hopefully) a reality.)
Yes, the 1000 times as energy dense is what lends it to being such an attractive idea for space travel as it saves so much weight. But it does not suggest that we could achieve a net energy gain. Fact is, because we do not have an antimatter mine anywhere we would have to make it ourselves. And due to the nature of matter-antimatter annihilation the best case scenario is that we get the same amount of energy out as we put in to make it, which isn't such an attractive property for a fuel.
You may be right, but in 50-75 years I hope mankind can prove you wrong.
You mean you hope in 50-75 years we prove the laws of thermodynamics wrong.... that would be really neat, but I'm not going to bet on it.
As for non perpetual motion machines providing long term energy. This sounds promising
Solar would only be useful if it was solar panels in space (they and putting them in space would have to be Much cheaper.. but there is plenty of space there)
Fusion would be more likely as a long term (of course it might be 30 years away for the next 500 years)
Kirk Sorensen actually worked on space solar power before getting into LFTR and found it to be completely unfeasible. He gets into a good discussion of it in his ProtoSpace talk at around the 12 minute mark.
What really stands out for me with regards to this technology is the part about being unable to turn the reactor materials into weapons. Will definately ease some tensions in the middle east (if we were using this technology now, tensions would not be mounting with Iran regarding their move to build neculear reactors for power). Likewise for places like North Korea, and countries we just generally do not trust with nuclear materials right now.
Also, it just seems like a way more pragmatic approach to power generation. Really hope this technology comes to fruition.
On January 28 2012 21:26 enemy2010 wrote: Two words: renewable energies.
I study energy ecomonics, and I personally thing this is the only way.
What does that even mean.
No energy source lasts forever. Every star will burn out, every molecule will decay, even black holes will evaporate to hawking radiation in the end. Entrophy reduces all to dust.
But ...
Until that happens I'm quite content for humanity to grab every resource it can get it's hands on to survive and make life easier. Whats not to love about this if it works as intended? Cheap fuel, trivial pollution and huge energy potential.
OP should include disadvantages with the technology as well. The general consensus among the reactor people where I study is that it is highly unsafe since it violates the fundamental defense-in-depth principle. Without the fuel cladding it's somewhat comparable to a PWR with a core meltdown. Because of this reason many consider the technology unrealistic.
Personally I wouldn't mind if more research is performed on molten salt reactors, since it would solve so many problems with generation IV (proliferation is a huge problem with other designs). But I'm not sure if the technology has a future.
If you want to be give a convincing argument, at least link us to a paper or two you've written comparing the costs and benefits of "renewable" energies to alternatives including LFTRs.
If you want to be give a convincing argument, at least link us to a paper or two you've written comparing the costs and benefits of "renewable" energies to alternatives including LFTRs.
No LFTRs have been built so it's impossible to say for certain how expensive power from one would be. Typically with a non-fossil fuel power plant fuel costs are relatively unimportant. Capital costs (construction, equipment, financing etc.) tend to matter the most.
With a yet unproven technology LFTRs would likely produce expensive energy initially and only be worth it if they were committed to on a large scale (build many, many LFTRs). This could only happen if the technology could be proven to be economic and governments and citizens were willing to clear away most of the regulatory hurdles that would get in the way of their construction.
If you want to be give a convincing argument, at least link us to a paper or two you've written comparing the costs and benefits of "renewable" energies to alternatives including LFTRs.
No LFTRs have been built so it's impossible to say for certain how expensive power from one would be. Typically with a non-fossil fuel power plant fuel costs are relatively unimportant. Capital costs (construction, equipment, financing etc.) tend to matter the most.
With a yet unproven technology LFTRs would likely produce expensive energy initially and only be worth it if they were committed to on a large scale (build many, many LFTRs). This could only happen if the technology could be proven to be economic and governments and citizens were willing to clear away most of the regulatory hurdles that would get in the way of their construction.
Right, I was mainly just going against the notion that thorium will run out while so-called "renewable" energy sources like geothermal, solar, and wind will not, (or at least that there will be a significant time-span difference).
I agree that capital costs and lobbying costs will matter the most for now.
As I understand it, Flibe Energy is trying to get the U.S. Military to adopt LFTRs for bases, which if successful, should pave the way for commercial use. As for getting the public to come along, this thread provides some evidence that there tends to be very little opposition among the those people who hear about it. However, there are some (exceptionally poorly researched) counter-attacks that some newspapers have published to try to be even-sided.
On January 28 2012 21:26 enemy2010 wrote: Two words: renewable energies.
I study energy ecomonics, and I personally thing this is the only way.
What does that even mean.
No energy source lasts forever. Every star will burn out, every molecule will decay, even black holes will evaporate to hawking radiation in the end. Entrophy reduces all to dust.
And lots of new stars are created everyday. Don't worry about entropy the universe is self-sustaining and in fact is self-increasing. It is anti-entropic.
On January 28 2012 21:26 enemy2010 wrote: Two words: renewable energies.
I study energy ecomonics, and I personally thing this is the only way.
What does that even mean.
No energy source lasts forever. Every star will burn out, every molecule will decay, even black holes will evaporate to hawking radiation in the end. Entrophy reduces all to dust.
And lots of new stars are created everyday. Don't worry about entropy the universe is self-sustaining and in fact is self-increasing. It is anti-entropic.
That makes no sense... the fact that it increases in volume has nothing to do with its energy. Also, how is it "self sustaining"? Eventually, as he said, stars burn out. Sure their remains can create other stars and such but eventually all energy will be gone.
On January 31 2012 07:46 Kupo wrote: OP should include disadvantages with the technology as well. The general consensus among the reactor people where I study is that it is highly unsafe since it violates the fundamental defense-in-depth principle. Without the fuel cladding it's somewhat comparable to a PWR with a core meltdown. Because of this reason many consider the technology unrealistic.
Personally I wouldn't mind if more research is performed on molten salt reactors, since it would solve so many problems with generation IV (proliferation is a huge problem with other designs). But I'm not sure if the technology has a future.
Without the fuel cladding? What do you mean exactly? The fuel is a fluid, without the cladding what would contain it? Without the fuel cladding PWRs wouldn't do so well. Is that an argument against PWRs? No, but there are plenty of other ones that you can't make about LFTR.
The MSRE ran for three years without incident, proving it can be done safely. If you watch the Kirk Sorensen's ProtoSpace talk he talks about how they used to turn the test reactor off on Friday and start it up again on Monday, the thing was so simple.
That it is a realistic viable solution was shown over 40 years ago. Many consider the technology unrealistic? Who are these people? And what are their arguments based on? Lots of people think that reptilians control the planet, should I listen to them? Of course not, they don't know what they are talking about.
On January 28 2012 21:26 enemy2010 wrote: Two words: renewable energies.
I study energy ecomonics, and I personally thing this is the only way.
What does that even mean.
No energy source lasts forever. Every star will burn out, every molecule will decay, even black holes will evaporate to hawking radiation in the end. Entrophy reduces all to dust.
And lots of new stars are created everyday. Don't worry about entropy the universe is self-sustaining and in fact is self-increasing. It is anti-entropic.
That makes no sense... the fact that it increases in volume has nothing to do with its energy. Also, how is it "self sustaining"? Eventually, as he said, stars burn out. Sure their remains can create other stars and such but eventually all energy will be gone.
How do you know this? The universe is constantly creating new galaxies. If energy is never created or destroyed, then how will all the energy eventually be gone? This view is not backed up by the evidence we have about the universe. In fact if you really want to get into quantum theory we can get into multiverses and resonance and discuss more about how much there is out there that seemingly has always been and will always be that we can't even see.
If you want to be give a convincing argument, at least link us to a paper or two you've written comparing the costs and benefits of "renewable" energies to alternatives including LFTRs.
No LFTRs have been built so it's impossible to say for certain how expensive power from one would be. Typically with a non-fossil fuel power plant fuel costs are relatively unimportant. Capital costs (construction, equipment, financing etc.) tend to matter the most.
With a yet unproven technology LFTRs would likely produce expensive energy initially and only be worth it if they were committed to on a large scale (build many, many LFTRs). This could only happen if the technology could be proven to be economic and governments and citizens were willing to clear away most of the regulatory hurdles that would get in the way of their construction.
Right, I was mainly just going against the notion that thorium will run out while so-called "renewable" energy sources like geothermal, solar, and wind will not, (or at least that there will be a significant time-span difference).
I agree that capital costs and lobbying costs will matter the most for now.
As I understand it, Flibe Energy is trying to get the U.S. Military to adopt LFTRs for bases, which if successful, should pave the way for commercial use. As for getting the public to come along, this thread provides some evidence that there tends to be very little opposition among the those people who hear about it. However, there are some (exceptionally poorly researched) counter-attacks that some newspapers have published to try to be even-sided.
Yeah I wouldn't quote that guy too much his "critical analysis" is very poorly done, full of errors. About the only point of his that is entirely correct is the technical challenge with the hastelloy pipes which has to be overcome. Almost everyone involved in the LFTR community will admit this is the biggest technical challenge, no one denies it. But on a scale of 1-10 of insurmountable human engineering challenges this is only 3-4 max.
You know the LFTR is a good match for your website title "TeamLiquid"
The liquid concept is exactly why this radically different design to a nuclear reactor is so much better. In a liquid state Fission gets more than one chance to get it right. Entropy is allowed to be maximized so that most of the fuel gets used up. Conventional solid fuel reactors leave 99% unburned. LFTRs are so much better. Read Superfuel by Richard Martin
If you want to keep up to date on trends in Nuclear Energy check out my blogs
On April 19 2012 05:18 RickMaltese wrote: You know the LFTR is a good match for your website title "TeamLiquid"
The liquid concept is exactly why this radically different design to a nuclear reactor is so much better. In a liquid state Fission gets more than one chance to get it right. Entropy is allowed to be maximized so that most of the fuel gets used up. Conventional solid fuel reactors leave 99% unburned. LFTRs are so much better. Read Superfuel by Richard Martin
If you want to keep up to date on trends in Nuclear Energy check out my blogs
Man oh man awesome, a Canadian as into Thorium and nuclear power as I am. Nice to meet you man. Definitely gonna be checking in on your websites often. All the best!
It does, though sadly not that often. Do a Google News search for Thorium, you will get some hits. Here is one of the links at the top of the search I just did:
China has revealed their schedule and many interesting details regarding their molten-salt reactor program.
They are making a slat-cooled reactor by 2015. If it goes well, then they expect a salt-fueled reactor by 2017. Then they will take several incremental steps scaling this reactor up. If every step is a success, commercial design will be available in 25-35 years.
Please have a look at this video for details (it's a new video that hasn't been posted here yet):
If it happens, it will be a revolution in Energy. If you haven't seen the following video, I think it explains it better than others (it has been posted in the thread, but I'd like to emphasize it once again):
I am not sure you will like that, but I am honestly lazy to go all through the material and have not seen a simple answer.
So, Is there anyone willing to explain to me are you going to convince anyone that you actually can contain the liquid fuel in the case of physical damage to the facility? It gets already quite difficult in water reactors (because even the water is a significant issue, although it has a tiny fravction of the overall radioactivity), and that is just water involved, not a highly corrosive molten salt.
This post is full of so many technical and scientific inaccuracies I don't even know where to begin. I don't know why there is a childish bandwagon obsession of thorium based technology but this has to stop.
The part where you said fluoride is less reactive than sodium is a red flag to a chemist let alone a physicist that this is total bullshit con job.//(I'll give you the benefit of the doubt and assume fluoride salts because liquid fluoride is literally the most reactive substance known to man. You can torch ice with it)
For those who ACTUALLY want to lean something the reason why we are not pursuing thorium based technology is three-fold. 1) It's more difficult to produce energy from however the ore is cheaper. This might change if a market developed. 2) The waste and implementation are exactly the same for all nuclear material. 3) We don't want to add another source of fuel into the world that needs to be regulated.
Even though I spent 7 years in the research of theoretical space-time geometries, the degree I'm pursuing is in Nuclear Engineering. Why NE? Because it's the highest paying tech job in the world so why the fuck not. Physics is physics.
3) We don't want to add another source of fuel into the world that needs to be regulated.
And this is another thing that makes me wondering thorough this entire topic. Is this really so important? There are all these sorts of argument about profiliteration and so on, but should we be really basing our technology sources on that? People/countries who want to obtain mass destruction capabilities will do it either way or another, why should we limit our energy technology because of that? And this argument is even weaker, there are so many regulated things, one more will not hurt anyone.
On October 04 2012 19:25 opisska wrote: I am not sure you will like that, but I am honestly lazy to go all through the material and have not seen a simple answer.
So, Is there anyone willing to explain to me are you going to convince anyone that you actually can contain the liquid fuel in the case of physical damage to the facility? It gets already quite difficult in water reactors (because even the water is a significant issue, although it has a tiny fraction of the overall radioactivity), and that is just water involved, not a highly corrosive molten salt.
If you don't use huge reactors with a lot of fuel, in smaller reactors in the case of physical damage to the reactor itself (for example a terrorist act) salt will cool down very quickly and crystallize. Then it's equivalent to solid fuel that just stays in one place.
There will also be no explosions, since nothing in a molten-salt reactor design has a large pressure differential (unlike current pressurised-water reactors).
If physical damage applies to anything else in the facility (not the reactor itself), than it does not matter at all, since in molten slat reactors you don't need any active cooling or any other engineered safety systems to prevent a meltdown. Molten slat reactors are passively safe even if you destroy all the facility but the reactor containment vessel and the drain tank itself.
On October 04 2012 19:48 Thenerf wrote: This post is full of so many technical and scientific inaccuracies I don't even know where to begin. I don't know why there is a childish bandwagon obsession of thorium based technology but this has to stop.
The part where you said fluoride is less reactive than sodium is a red flag to a chemist let alone a physicist that this is total bullshit con job.//(I'll give you the benefit of the doubt and assume fluoride salts because liquid fluoride is literally the most reactive substance known to man. You can torch ice with it)
For those who ACTUALLY want to lean something the reason why we are not pursuing thorium based technology is three-fold. 1) It's more difficult to produce energy from however the ore is cheaper. This might change if a market developed. 2) The waste and implementation are exactly the same for all nuclear material. 3) We don't want to add another source of fuel into the world that needs to be regulated.
Even though I spent 7 years in the research of theoretical space-time geometries, the degree I'm pursuing is in Nuclear Engineering. Why NE? Because it's the highest paying tech job in the world so why the fuck not. Physics is physics.
I agree that the OP is not very good and has quite a few mistakes.
Thorium seems to be just a hype word to calm down those who fear uranium and plutonium. The real goal in this research is a molten salt reactor (powered by whatever nuclear fuel you want to use). The only real advantage of thorium over uranium in breeders is that it's harder to make nuclear weapons from thorium (since U232 [that is difficult to separate from U233] is a strong gamma emitter). For the near term I believe that the focus in this research should be on uranium/plutonium-powered molten salt reactors. The design is just very nice: it's passively safe (no meltdowns possible, no cooling required), reduces waste through simple in-situ reprocessing, does not need thick steel walls or huge containment buildings etc.
p.s. Do you think NE really has a future outside of China and some other developing countries, or are you planning to move there after you get a degree? It seems to me that a lot of countries (quite probably US in the near future as well) are looking towards gradually excluding nuclear energy from their energy portfolio.
The funny thing is lots of money is being spent on developing nuclear power everywhere. The Obama and Bush administration have already allocated money for research and construction of new nuclear plants here in the US. Europe is always looking for a way to "appear" high tech and the east is looking for cheaper safety mechanisms. There is an emerging and current strong market right now for QUALIFIED engineers.
I also like to add that I don't believe sodium reactors will ever gain popularity for the same reasons MERCURY reactors failed in Russia. On paper, when everything is going according to plan, they seem efficient only to find out that when anything goes wrong you have a destroyed, highly toxic reactor. Water based cooling is just fool proof assuming the country (/cough.....Russia) doesn't take fool to a whole new level.
I'm looking over the designs for these theoretical reactors and they don't seem to have a good way to control the nuclear reaction, to assume that the reaction will sustain ITSELF....well goes back to bringing fool to a whole new level concept. One of the advantages of the current reactors is the ease at which we can make them go hot and cold while at the same time the initial fuel is safe enough to handle while the reactor is being set up. According to my research these reactors would be dangerous 24/7.
On October 04 2012 19:25 opisska wrote: I am not sure you will like that, but I am honestly lazy to go all through the material and have not seen a simple answer.
So, Is there anyone willing to explain to me are you going to convince anyone that you actually can contain the liquid fuel in the case of physical damage to the facility? It gets already quite difficult in water reactors (because even the water is a significant issue, although it has a tiny fravction of the overall radioactivity), and that is just water involved, not a highly corrosive molten salt.
The molten salt is not held at pressure, like the water is in PWRs, so if there is a leak/malfunction the molten salt would spill on to the floor and be contained by the steel walls. It would be messy, but it would be 100% containable and would not affect the surrounding neighborhood. And in real life the odds of this happening are about zero, since there are numerous safety considerations for the molten salt to drain safely into the drain tank in an emergency. But in the very small chance that it leaks out of the machine, it would not escape the containment walls.
On October 04 2012 19:48 Thenerf wrote: This post is full of so many technical and scientific inaccuracies I don't even know where to begin. I don't know why there is a childish bandwagon obsession of thorium based technology but this has to stop.
The part where you said fluoride is less reactive than sodium is a red flag to a chemist let alone a physicist that this is total bullshit con job.//(I'll give you the benefit of the doubt and assume fluoride salts because liquid fluoride is literally the most reactive substance known to man. You can torch ice with it)
For those who ACTUALLY want to lean something the reason why we are not pursuing thorium based technology is three-fold. 1) It's more difficult to produce energy from however the ore is cheaper. This might change if a market developed. 2) The waste and implementation are exactly the same for all nuclear material. 3) We don't want to add another source of fuel into the world that needs to be regulated.
Even though I spent 7 years in the research of theoretical space-time geometries, the degree I'm pursuing is in Nuclear Engineering. Why NE? Because it's the highest paying tech job in the world so why the fuck not. Physics is physics.
FLOURINE is more reactive than Sodium, but FLUORIDE, in this case a Fluoride salt with Beryllium and Lithium, is very stable.
Waste management and disposal for a LFTR would be radically different than the current method of storage pools, or re-processing in places like France. Almost all the fuel would be burned up in the reactor over time. You would not have only 1% or so of the fuel used before it becomes too brittle like the solid fuel in current reactors.
On October 05 2012 00:51 Thenerf wrote: @Alex1Sun
The funny thing is lots of money is being spent on developing nuclear power everywhere. The Obama and Bush administration have already allocated money for research and construction of new nuclear plants here in the US. Europe is always looking for a way to "appear" high tech and the east is looking for cheaper safety mechanisms. There is an emerging and current strong market right now for QUALIFIED engineers.
I also like to add that I don't believe sodium reactors will ever gain popularity for the same reasons MERCURY reactors failed in Russia. On paper, when everything is going according to plan, they seem efficient only to find out that when anything goes wrong you have a destroyed, highly toxic reactor. Water based cooling is just fool proof assuming the country (/cough.....Russia) doesn't take fool to a whole new level.
I'm looking over the designs for these theoretical reactors and they don't seem to have a good way to control the nuclear reaction, to assume that the reaction will sustain ITSELF....well goes back to bringing fool to a whole new level concept. One of the advantages of the current reactors is the ease at which we can make them go hot and cold while at the same time the initial fuel is safe enough to handle while the reactor is being set up. According to my research these reactors would be dangerous 24/7.
Water based cooling is fool proof (at 150 atm of pressure, Fukushima anyone?) while molten salt held at normal pressure would be dangerous 24/7? Where are you getting this from? I am currently doing a B.Eng in Electrical and plan on doing a Masters in NE as well.
On October 05 2012 02:59 LaSt)ChAnCe wrote: now, how can we take this beautiful idea... and make it into a bomb?
Thorium is not fissile, it is fertile. It can be made into Uranium 233, which is fissile. But U-233 is not very convenient for making bombs with. That is one of the things that make this idea so beautiful.
EPT
18] uranium is to be removed from the fuel as the hexafluoride by adding excess fluorine, and plutonium as the plutonium dioxide by adding sodium carbonate.![[image loading]](http://i.imgur.com/6jzqQ.png)
