Thorium reactor discussion thread!

[lajoswinkler]

When you build nuclear powerplants to be safe (which is possible, but hard), they get so ....ing expensive that right now even solar+batterys is cheaper.

If by "safe" you mean "does not cause problems of any kind, nor kills anyone in its whole life cycle", then nothing is safe. In reality, there is no 100% safe and environmentally friendly energy source. Some of them kill in the long run in front of your face (coal), some of them kill in the long run away from your face (solar panels).

The point is that anyone who tries to compare nuclear fission with solar photovoltaics as if they're on the same level of hierarchy, shows their ignorancy on the subject matter.

Those two things are not replaceable and will never be because energy sources differ in a lot more than just amount of power they deliver.

Things can be "safe enough". There is a calculable and tolerable amount of risk in everything.

Ok, I get it, it is pretty safe... but does making deep underground power plants would make them any safer? Or cheaper, since this "tombs" probably cost a lot?

You still need a containment building, so it's easier to build it above ground than digging a hole, first. Unless we're talking about a bunker buster attack, it doesn't make them safer, just more expensive to build.

[sgt_flyer]

One thing comes to mind though with all this talk - Power density is also of importance and has to be taken into account (especially on islands like japan, were space comes at a premium - unless you build your renewable energy over water, which will increase maintenance costs (storms, corrosion) and might cause fishing problems (notably for japan which is extremely dependant on fishing)

Found an article describing the power densities problems (and remember that people also need to eat - so you need farmland) :

http://www.theenergycollective.com/robertwilson190/257481/why-power-density-matters

And one interesting point of this article, is to see how much energy / people is required (notably for occidental lifestyle countries)

So - wouldn't trying to make everything more and more energy efficient be also a good way to limit pollution ?

[Shpaget]

Interesting argument. So if one technology kills people then other technology that cause deaths is fine?

Everything kills people.

The trick is to find the stuff that kills the least, and when taken into account the amount of energy produced, nuclear has a pretty good record.

I am also talking about perspective. A few deaths caused by an accident pale in comparison with the number of deaths that occur on regular basis.

[Darnok]

Everything kills people.

The trick is to find the stuff that kills the least, and when taken into account the amount of energy produced, nuclear has a pretty good record.

I am also talking about perspective. A few deaths caused by an accident pale in comparison with the number of deaths that occur on regular basis.

If something kills people maybe we should get rid of that and try to develop technology based on new concept?

What is more important human life, profit or life style?

[peadar1987]

If something kills people maybe we should get rid of that and try to develop technology based on new concept?

What is more important human life, profit or life style?

If we stopped generating power, how would we manufacture drugs, build hospitals, communicate with each other about research that improves the lives of everyone? No matter what we do, people are going to die, grim as that may be. Generating power using the safest sources we know, while investing in research to make them even safer still is the best option.

[Shpaget]

If something kills people maybe we should get rid of that and try to develop technology based on new concept?

What is more important human life, profit or life style?

Do we get rid of it before or after we develop a new concept?

[SomeGuy12]

So, exactly how much cheaper and/or better will thorium reactors be?

As I understand it, they are just a form of breeder reactor where the breeding happens inside the core, so you aren't having to constantly cycle out hot fuel, reprocess it while it is hot, and then insert hot replenished fuel rods. That does make breeding a lot more practical.

However, as I understand it, the cost of the fuel is still negligible compared to the cost of everything else. So how does a thorium reactor make the economics of nuclear work better for right now?

[sgt_flyer]

So, exactly how much cheaper and/or better will thorium reactors be?

As I understand it, they are just a form of breeder reactor where the breeding happens inside the core, so you aren't having to constantly cycle out hot fuel, reprocess it while it is hot, and then insert hot replenished fuel rods. That does make breeding a lot more practical.

However, as I understand it, the cost of the fuel is still negligible compared to the cost of everything else. So how does a thorium reactor make the economics of nuclear work better for right now?

The thorium needed for MSRs is basically natural thorium - much more abundant than natural uranium - and it doesn't need heavy fuel processing (centrifuges and such) to be transformed into usable fuel.

thorium MSR (Molten Salt Reactor) don't use fuel rods - it basically uses fuel in liquid form at operating temperatures. The fuel directly becomes the primary loop which is pumped in and out of the reactor. After the primary loop heat exchangers, the still liquid fuel is cleaned of decay products (much easier to reprocess liquids than solid fuel rods) before being reinjected in the reactor core. (The fuel is cannot go critical in itself - the initial reaction needs to be kickstarted (one of those kickstart means being weapon's grade uranium, and is sustained thanks to the breeding and the moderators in the reactor)

One of the problems with solid fuel rods, is that once the transmutation of the fuel rod into it's decay products goes over a certain treshold (and even only a few % of transmuted material is enough) the reaction cannot sustain itself (because the neutrons have more chance to hit non fissile byproducts) - so the fuel rod has to be taken out and either reprocessed - or discarded, which creates a lot of waste. With molten salt constant reprocessing, they want to extract only the byproducts, which would allow to create less waste.

Some proposed highlights of the MSR design :

if the fission rate starts to accelerate, the liquid would expand naturally from thermodynamic laws, and the resulting additional space between fissile atoms would mean that more neutrons are lost - so the reaction is supposed to be able of a certain amount of self regulation.

The molten salts can run at much higher temperatures (as much as 850°C) (as they don't have risks of damaging the fuel rods) - would give higher temperatures for the secondary loop, enabling the use of more efficient steam turbines.

The molten salts also operate at low pressure, simplifying the reactor's design.

Security measures :

the reactor can be emptied from it's fuel through gravity - in case of failure, there is basically supposed to be an actively cooled cap in the primary loop - if the power fails / primary loop pumps stop, the cap is not cooled anymore and melts - the fuel then flows thanks to gravity directly inside a containment under it.

Downsides :

molten salts at these temperatures are very corrosive, so you need to build out of materials able to withstand that (and some of those can embrittle...)

Each reactor would need it's own small reprocessing fuel plant to extract the byproducts.

Also, Current production of the weapon grade uranium needed to initiate the reaction is nowhere near enough to sustain a country wide thorium MSR power plants. You could also use reactor grade plutonium to initiate the reaction, but it would end up generating much more byproducts to be cleaned out of the fuel afterwards.

Edited October 12, 2015 by sgt_flyer

[Elthy]

Having the thorium outside of a well definded reactor core makes small leaks of radiation way more likely. Not catastrophic, but still not nice for the plant...

[NuclearNut]

Having the thorium outside of a well definded reactor core makes small leaks of radiation way more likely. Not catastrophic, but still not nice for the plant...

Actually the big problem is the onsite reprocessing which would be absolutely necessary. It is a problem because you would need to chemically process highly radioactive material at every reactor everywhere, unlike in a conventional uranium-plutonium breeder reactor.

And, if you look at the whole thing in a bit different of a way, the problem is not that it requires chemical processing, but the fact that our experience with running small chemical reprocessing plants in nuclear power stations is basically nonexistent, whereas we already know how to run a liquid metal fast breeder reactor.

[PB666]

Everything kills people.

The trick is to find the stuff that kills the least, and when taken into account the amount of energy produced, nuclear has a pretty good record.

I am also talking about perspective. A few deaths caused by an accident pale in comparison with the number of deaths that occur on regular basis.

We should make the reactor out of solar nerf balls, doesn't kill people, light weight and you could just roll it out on string.

Win, win, win...........heh-heh.

[SomeGuy12]

So, you have reduced the risk of a core burn through, but now you have lethally radioactive liquid metal that you have to pipe around, including through a complex series of chemical reaction stations.

Among other things, it sounds to me that you could end up with an accident where the metal comes into contact with the water used for the steam turbine loop and flashes it into steam, carrying away bits of the reactor with it. Unlike fuel rods for a conventional reactor, it sounds like the actual lethally radioactive core stuff is kind of evenly mixed instead of normally being trapped in a fuel rod. I'm not using the word "lethal" for dramatic effect - as I understand it, direct line of sight exposure to a moderate quantity of stuff this radioactive is a lethal dose in seconds, similar to the danger of the Elephant's foot at Chernobyl. The EF wasn't pure fuel core either, it was a mixture of melted fuel rod, melted reactor core lining, melted concrete, and the actual fuel.

It also doesn't sound trivial to contain if stuff goes badly enough. If that liquid metal flows everywhere and contaminates a damaged reactor building, it's basically the kind of mess that you have to wait 50 years before you can even begin the cleanup.

Causing mass death? No, but little flakes of a liquid metal core would probably contaminate surrounding agricultural land enough that you can't use it, causing a loss of that land value. That's a big liability to incur to build one of these.

To me, Thorium does not sound like the way. Currently, the cheapest and most practical way is :

Build solar panels, wind generators, and natural gas turbines.

Is it night and the wind is calm? Burn the natural gas. Is it daytime and there is too much solar power compared to demand? Use the excess solar energy to compress air and store it in caverns under the natural gas generators.

Currently, as I understand it, that mix is the cheapest. Existing nuclear reactor designs are already too expensive to even compete, and thorium reactors, while they might ultimately have cost advantages if they run at higher temperatures and need cheaper fuel, would be even more expensive initially.

Farther in the future, for spaceflight, if you are using NERVA engines, you wouldn't use thorium either, right? You'd use weapons grade U-235 or pure plutonium for you reactor fuel core, because anything else is adding mass. And, fusion, if we ever did get it working (yeah, yeah, always 50 years away), is more ideal for both spaceflight (lighter reactor designs are possible) and on the ground (no load of tons of fissionables that you have to keep contained)

Edited October 13, 2015 by SomeGuy12

[NuclearNut]

So, you have reduced the risk of a core burn through, but now you have lethally radioactive liquid metal that you have to pipe around, including through a complex series of chemical reaction stations.

If you are using a molten salt reactor, yes, you have to have onsite reprocessing and the fuel salt material is quite radioactive. In a lead or sodium cooled fast reactor that is not the case as the fuel rods are solid and reprocessing can be done offsite.

Among other things, it sounds to me that you could end up with an accident where the metal comes into contact with the water used for the steam turbine loop and flashes it into steam, carrying away bits of the reactor with it. Unlike fuel rods for a conventional reactor, it sounds like the actual lethally radioactive core stuff is kind of evenly mixed instead of normally being trapped in a fuel rod. I'm not using the word "lethal" for dramatic effect - as I understand it, direct line of sight exposure to a moderate quantity of stuff this radioactive is a lethal dose in seconds, similar to the danger of the Elephant's foot at Chernobyl. The EF wasn't pure fuel core either, it was a mixture of melted fuel rod, melted reactor core lining, melted concrete, and the actual fuel.

In a MSR your concern would indeed be the primary coolant loop (PCL) breaching and mixing with the secondary coolant loop (SCL), that is the concern with all reactors that do not use water as a coolant. Now mind, in the place that this will happen, the steam boilers, the water already flashes into steam on a regular basis, in this case for the turbines. So a leak into the steam boiler would be a... leak into boiler. It would require the expected removal effort and cleaning operation, probably resulting in replacement of a few pipes.

The above is true for lead, water, and molten salt coolants, now if you were to be talking about sodium, well sodium is sodium, and to deal with it an extra loop is added containing non-radioactive sodium. The same could probably be done in a MSR or LCFR to deal with any leakage from the PCL to the water loop.

It also doesn't sound trivial to contain if stuff goes badly enough. If that liquid metal flows everywhere and contaminates a damaged reactor building, it's basically the kind of mess that you have to wait 50 years before you can even begin the cleanup.

Actually that sounds really, really easy to contain. Molten salt at around 400 degrees celsius would be nice in two ways. First it would spread out loosing criticality very quickly, it would convect well, possibly (assuming the containment spreading pool is large enough) allowing for complete decay heat removal, cooling it down quite rapidly, allowing the building to be filled with water and the material scraped off. If you make a dedicated core spreading pool like in all proposed MSR designs you would just heat up the pool and drain it into specialized casks, no scraping required (unlike in a solid fuel rod reactor)

The problem with containment vessels in conventional reactors is the threat of steam explosion and pressures exceeding the reactor vessel's max overpressure resulting in rupture and radioactive materials release.

Causing mass death? No, but little flakes of a liquid metal core would probably contaminate surrounding agricultural land enough that you can't use it, causing a loss of that land value. That's a big liability to incur to build one of these.

Know what a wonderful thing about nuclear reactors is? You can detect most all the radioactive materials in the sity the facility, and track them all, thus making it so that the airlocks can be scrubbed if anything ever gets there, preventing even small releases of harmful material. As many "little flakes of metal" would leave a nuclear power station using a MSR or any other reactor design, that is to say none on a regular basis.

To me, Thorium does not sound like the way. Currently, the cheapest and most practical way is :

Build solar panels, wind generators, and natural gas turbines.

Is it night and the wind is calm? Burn the natural gas. Is it daytime and there is too much solar power compared to demand? Use the excess solar energy to compress air and store it in caverns under the natural gas generators.

Currently, as I understand it, that mix is the cheapest. Existing nuclear reactor designs are already too expensive to even compete, and thorium reactors, while they might ultimately have cost advantages if they run at higher temperatures and need cheaper fuel, would be even more expensive initially.

Why not just use natural gas only, your setup as your wind and solar will only work 30% of the time. It also seems a tad dirty to use natural gas, which has the wonderful world of hydraulic fracking and unchecked emissions into the world. Yes, natural gas is cheap, it is also a lot dirtier than nuclear.

Oh, and reactors do have really, really cheap O&M (operating and maintenance), they just cost a quite a bit to set up, which is interestingly enough the opposite of natural gas.

Farther in the future, for spaceflight, if you are using NERVA engines, you wouldn't use thorium either, right? You'd use weapons grade U-235 or pure plutonium for you reactor fuel core, because anything else is adding mass. And, fusion, if we ever did get it working (yeah, yeah, always 50 years away), is more ideal for both spaceflight (lighter reactor designs are possible) and on the ground (no load of tons of fissionables that you have to keep contained)

You would some source of HEU (high enriched uranium) or plutonium for the reactor, and using just plain gas centrifuge separation for uranium is incredibly expensive and would give you a small amount of material to work with (it is impossible to get plutonium in a good quantity without a reactor). Instead, you could generate a lot of electricity on the side using a MSR breeder reactor and get high enriched uranium through comparatively simple chemical reprocessing, or use a fast breeder reactor to produce plutonium and use chemical reprocessing.

I do agree with you that fusion would be ideal for everything, primarily from a resource use standpoint (far easier to get deuterium than uranium), however I believe until then we need fission.

[sgt_flyer]

Using sodium for primary or secondary loop comes with it's own problems though - in case of sodium leakage, hot sodiul m would catch fire immediately at ambient atmospheric pressure (and good luck extinguishing a mass spill of sodium - and to keep it away from water )

@someguy

The windfarms/solar farms with underground storage have special requirement though - you need to have such geologic structures avaible on hand for pressurised air (and imagine the amount of land you'll need to cover to match a nuclear or classic power plant)

Solar panels have a terrible w/m2 performance (especially if you are in less sunny countries) and you need to keep wind turbines apart from each other. (Else the resulting wind vortices would lower the other wind turbines efficacity - and those turbines have a huge concrete feet to hold them upright)

If we want to limit our dependancy on nuclear power / classic power plants, maybe we can try to lower the needed baseload at first ? (which means to try to waste less electricity all around the year ) - more efficient house insulation, more efficient industrial machinery, etc - would allow to both lower the overall energetic mix load needs - less power plants needed

[peadar1987]

Molten salt reactors don't use metal as their coolant, they use metal salts, which are far less reactive (although not without their own problems. They really don't play well with metals for example, so everything has to be made of graphite. Which itself doesn't like neutrons)

[KerikBalm]

As I understand it, the main advantage is:

The half lives of the waste are much much much less than in Uranium reactors...

You'd only need to store the waste for centuries, rather than millenia... it may not sound like much of a distinction now... but it would make a big difference to your grandkids.

Also, Thorium reactors aren't really conducive to weapons proliferation. There's no need for all those centrifuges... there's just that startup problem... and then you're done.

The startup of a reactor could be overseen by the international atomic energy commission or whatever it is called... then they leave and that reactor never needs any more enriched uranium/plutonium. A country such as Iran that wants nuclear power could easily negotiate an agreement to get the startup material, start their reactors... and abandon *all* enrichment activities.

If thorium reactors are running, there is absolutely no legitimate need for continued uranium enrichment.

* No Nuclear weapons

* No major riskof a criticalitiy incident/nuclear meltdown/ much smaller risk of a nuclear disaster.

* In a millenia, civilization won't still be dealing with problems we created

* Thorium is much more abundant than U-235

* We had working Thorium reactors in the 60's, and they were abandonded because they weren't "dual use" and weren't usefull to the US atomic weapons program.

In an era where the US and Russia are not increasing nuclear stockpiles, I really wonder why we haven't switched to Thorium reactors.

https://en.wikipedia.org/wiki/Thorium-based_nuclear_power#Background_and_brief_history

During that period, the U.S. government also built an experimental molten salt reactor using U-233 fuel, the fissile material created by bombarding thorium with neutrons. The reactor, built at Oak Ridge National Laboratory, operated critical for roughly 15000 hours from 1965 to 1969. In 1968, Nobel laureate and discoverer of Plutonium, Glenn Seaborg, publicly announced to the Atomic Energy Commission, of which he was chairman, that the thorium-based reactor had been successfully developed and tested:

So far the molten-salt reactor experiment has operated successfully and has earned a reputation for reliability. I think that some day the world will have commercial power reactors of both the uranium-plutonium and the thorium-uranium fuel cycle type.[7]

In 1973, however, the U.S. government shut down all thorium-related nuclear researchâ€â€which had by then been ongoing for approximately twenty years at Oak Ridge National Laboratory. The reasons were that uranium breeder reactors were more efficient, the research was proven, and byproducts could be used to make nuclear weapons.

...

Science writer Richard Martin states that nuclear physicist Alvin Weinberg, who was director at Oak Ridge and primarily responsible for the new reactor, lost his job as director because he championed development of the safer thorium reactors.[8][9] Weinberg himself recalls this period:

[Congressman] Chet Holifield was clearly exasperated with me, and he finally blurted out, "Alvin, if you are concerned about the safety of reactors, then I think it may be time for you to leave nuclear energy." I was speechless. But it was apparent to me that my style, my attitude, and my perception of the future were no longer in tune with the powers within the AEC.[10]

Martin explains that Weinberg's unwillingness to sacrifice potentially safe nuclear power for the benefit of military uses forced him to retire:

Weinberg realized that you could use thorium in an entirely new kind of reactor, one that would have zero risk of meltdown. . . . his team built a working reactor . . . . and he spent the rest of his 18-year tenure trying to make thorium the heart of the nation’s atomic power effort. He failed. Uranium reactors had already been established, and Hyman Rickover, de facto head of the US nuclear program, wanted the plutonium from uranium-powered nuclear plants to make bombs. Increasingly shunted aside, Weinberg was finally forced out in 1973.

[sgt_flyer]

Oakridge MSRE only used uranium based salts (U-233 and U-235) - and was pretty safe, as the primary loop was kept at all time inside the reactor confinment. They used uranium bred from thorium, but never directly used thorium in it.

And it never had in situ reprocessing directly integrated with the primary loop - so that's one key part of today's design that was never tested

[Elthy]

All the technologys you mention are very advanced and (almost) never tested. The developement costs would be gigantic..

[KerikBalm]

Very advanced and almost never tested????

They had a working thorium reactors in the 60's...

They ran it for years - 15000 thousand hours of operation...

Stuff from the 60s is very advanced?

15000 hours of operation is almost never tested?

Please....

They shut them down because they wanted stuff they could use to make bombs.

We have plenty of bombs.

We should be using thorium reactors.

[sgt_flyer]

We never had a single working fully sustained thorium cycle (even if they did test uranium bred from thorium, the breeding occured elsewhere, and they simply added the bred uranium to the reactor)

The only molten salt reactors in 1960s were MSRE and ARE and both directly used only uranium

And they did not have the reprocessing capability integrated with the primary loop - so the fuel would become less and less capable of sustaining the reaction over time (unless they flush out the reactor and replace the whole fuel)

The basics were there, but largely incomplete. In modern designs, you would have to either keep both the primary loop and the reprocessing unit within the reactor confinment (imagine the size needed for that) or to make the primary loop go outside of the reactor confinment to get to reprocessing.

Besides, the molten salts used were fluorine based... Fluorine which could escape the fuel as gases from low temperatures radiolysis. (They had to keep the fuel at 150°C until 1989's - and even then, they estimated a 1 ATM of fluorine gas. (And even uranium hexafluoride gas when they finally cleaned up MSRE in the 2000s)

Ok, modern designs take into account this problem, but those modern designs have yet to be built for the moment.

[SomeGuy12]

Ok, so, to summarize :

Thorium reactors have the potential of higher power density per core, cheap, near infinite fuel, and less worry about people making nuclear warheads as a side bonus.

They have the disadvantage of requiring a lot of technological development, and the liquid fuel you have mentioned is inherently harder to control than solid rods. It also means you need a number of pieces of machinery to conduct reprocessing on the fuel, and those pieces of machinery will be so hot to give someone a lethal dose in a minute or less, probably too hot to work on with waldos behind glass - you'd probably be forced to use remote cameras. Also, when the machinery breaks, it is really hard to fix and it's high level radioactive waste in itself, kind of negating any reduced waste advantages of thorium.

And this means that thorium reactors share the other huge disadvantage of nuclear. Once you fuel one of these puppies and put it into service, you have created a place that contains literal tons of lethal poison that has a tendency to escape containment. This can be dealt with, but it means you must spend large sums of money building a containment facility with many many redundant and expensive layers of protection. You can't pinch pennies anywhere - cheaper equipment, cheaper people, etc, all raise the risk of an accident.

I don't see it. What are you guys seeing that I'm not? New nuclear is already more expensive than new wind. Yeah, yeah, "baseload", but new nuclear is also more expensive than new wind and sufficient backup generators to run when the wind dies. Someone upthread thought that wind + solar only works 30% of the time, that's absurd and not based on real numbers (I've seen articles indicating it is much higher because over a large geographic area, the probability is very high there is significant sun or wind in parts of it, at any time, day or night). In any case, the gas backup turbines are cheap, the cheapest form of power at the present, wind and solar is just to reduce your fuel costs to less than half.

It's not going to happen. (thorium or even a significant nuclear resurgence). The fundamental problem is that solar and wind and batteries are going to keep getting cheaper, because there are a lot of competitors, and there is room to innovate. If you come up with an innovative new windmill, battery, or solar panel design, and it fails prematurely, all that happens is some warranty claims and unhappy customers. If you think of a way to save money on a nuclear reactor, well, you see the problem. Tepco thought they could save a few million by building a lower protective wall. They also didn't pay for the auxillary steam turbine option package, or a transformer set to power their own plant from their own reactor power, or even 1 extra backup generator located higher up, nothing.

[NuclearNut]

Ok, so, to summarize :

Thorium reactors have the potential of higher power density per core, cheap, near infinite fuel, and less worry about people making nuclear warheads as a side bonus.

Correct, though the high power density, cheap fuel, and less worry about nuclear weapons is something all nuclear power has in common.

They have the disadvantage of requiring a lot of technological development, and the liquid fuel you have mentioned is inherently harder to control than solid rods. It also means you need a number of pieces of machinery to conduct reprocessing on the fuel, and those pieces of machinery will be so hot to give someone a lethal dose in a minute or less, probably too hot to work on with waldos behind glass - you'd probably be forced to use remote cameras. Also, when the machinery breaks, it is really hard to fix and it's high level radioactive waste in itself, kind of negating any reduced waste advantages of thorium.

No one denied the research would be needed, you need research for wind and solar, expensive research at that. The fuel is also not "inherently harder to control" than solid fuel, they all have their problems, but a MSR would not be inherently harder.

Oh, and that waste from the core lasts only 70 or so years before it can be re-cycled into new reactor cores. Oh, and the reprocessing equipment, if properly cleaned and drained of fuel material, will be completely non-radioactive and safe to handle. This is because it was not exposed to a high neutron flux for a long time, unlike the core.

And this means that thorium reactors share the other huge disadvantage of nuclear. Once you fuel one of these puppies and put it into service, you have created a place that contains literal tons of lethal poison that has a tendency to escape containment. This can be dealt with, but it means you must spend large sums of money building a containment facility with many many redundant and expensive layers of protection. You can't pinch pennies anywhere - cheaper equipment, cheaper people, etc, all raise the risk of an accident.

With this the containment can be like any other containment, heck, with this you do not need backup generators because the radioactive material can just be poured into a core spreading pool without any concerns, unlike in a conventional facility where the core material going into a core spreading pool is impossible because it is solid. So right there you have eliminated backup generators, most emergency coolant loops, and other such things. At this point the big redundant layer would need to be the containment vessel itself, nothing more.

Oh, yeah, and tons:

I present to you a whole thirty years of nuclear waste from one 1000 MWe nuclear power station (enough to provide the electrical energy for 600 000 people, assuming the average per capita energy consumption for the US), three of those containers (the ones on the very right if I am not mistaken) are the reactor core itself, which can be re-cycled in around sixty years. The rest are simply fuel rods bundled into a shielded container. These fuel rods have not been re-processed, thus they have quite a bit more volume than the actual waist portion of them. If they were re-processed only two of those containers would be there. In a MSR it would always be re-processed, and thus extremely low volume.

I don't see it. What are you guys seeing that I'm not? New nuclear is already more expensive than new wind. Yeah, yeah, "baseload", but new nuclear is also more expensive than new wind and sufficient backup generators to run when the wind dies. Someone upthread thought that wind + solar only works 30% of the time, that's absurd and not based on real numbers (I've seen articles indicating it is much higher because over a large geographic area, the probability is very high there is significant sun or wind in parts of it, at any time, day or night). In any case, the gas backup turbines are cheap, the cheapest form of power at the present, wind and solar is just to reduce your fuel costs to less than half.

The thirty percent figure I agree was a tad optimistic, it would most likely be less. That is simply because the highest capacity factor at the largest wind farm in the world was, guess what, 30%. A mere 30% is pathetic. But let's just say in our world that the wind never blows when the solar panels are at peak capacity, well then you get 50%, which is half of the time, a half that will be off peak hours and other such times, making it so that you must now use natural gas far more than 50% or 30% of the time.

And yes, turbines are cheap, but they are limited (less than a hundred years of fuel left, for the US alone), and they require fracking, which hopefully you know about. If you do not, well let me explain it to you. Fracking is the process where you drill a regular oil well, and then pump down thousands of gallons of fracking fluid, hoping that that does not cause the natural gas to escape into anywhere else than your oil well. It is generally quite polluting and nasty, far nastier than uranium mining or nuclear power. Oh, and unlike nuclear power, it emits quite a bit of CO2, making it no solution to global warming.

It's not going to happen. (thorium or even a significant nuclear resurgence). The fundamental problem is that solar and wind and batteries are going to keep getting cheaper, because there are a lot of competitors, and there is room to innovate. If you come up with an innovative new windmill, battery, or solar panel design, and it fails prematurely, all that happens is some warranty claims and unhappy customers. If you think of a way to save money on a nuclear reactor, well, you see the problem. Tepco thought they could save a few million by building a lower protective wall. They also didn't pay for the auxillary steam turbine option package, or a transformer set to power their own plant from their own reactor power, or even 1 extra backup generator located higher up, nothing.

Actually the solution to costs in modern reactors is getting rid of the backup generators, secondary coolant pumps, and excess piping. They are also quite a bit safer and cheaper due to this. This is because they have either natural circulation for coolant, as in the ESBWR, or they have a large water tank on top of the reactor and convection cooling for the sides, as in the AP-1000. Both of those are far safer than a regular reactor, cheaper to build, and cheaper to operate. Nuclear is also innovating, we have several initiatives to develop new reactor concepts such as the MSR, Lead Cooled Fast Reactor, Supercritical Water Reactor, High Temperature Gas Reactor, and others. While wind and solar are getting cheaper, nuclear is doing likewise, and in doing so also getting safer than previous versions.

EDIT:It should also be noted that, separate from this post, that the thorium fuel cycle has already been tested and conducted with breeding during the 1970s at the shippingport nuclear power station. It worked in a light water reactor, generating 2% more fuel than put in. This is something to note in this matter as there is more than one way to use the thorium fuel cycle.

Edited October 13, 2015 by NuclearNut
added mention of shippingport PWR

[sgt_flyer]

Yup, thorium breeding has been done, but not the full reprocessing in 'hot' conditions of the molten salts (basically, the full primary loop with reprocessing of modern MSR designs)

Most of the MSR components were tested separately in one form of another, but never all at once in a single design

Else,i think one of the problems that nuclear power face (barring some inherently flawed reactor designs - that's another problem - most power plants designs and procedure make it safe) is that they suffer from a lot of bad press. (Maybe because it's something we can easily 'see' (with the huge vapor clouds rising from the cooling towers - that comes from a 'nuclear power plants') - in people mind, columns of smoke coming from chimneys is a but akin to 'pollution' and nuclear power plants cooling towers are gigantic.

That 'visibility' is one of the problems when trying to convince the vast majority, because they concentrate on things they can see.

Whereas people don't see the production chains for 'green' power, like rare earth mines which are needed for the production of notably solar panels.

And they don't easily see the power density problems - for a majority of people, a solar panel or a wind turbine makes electricity basically for 'free' while we need 'fuel' for other systems - and because it's free, it can provide has much as they need.

In reality - it's nowhere not enough in terms of power density. (And it's not that cheap regardless of incentives)

Here's a quick comparison, between the ivanpah solar thermal power facility (and those mirrors needs much less rare earth than solar panels) (377Mw net power) - terrain size - around 1420 ha (all covered in mirrors) - cost 2.2 billion.

Seabrook nuclear power plant (finished in 1990 with huge delays)the whole power plant roughly fits in a 1 by 1 km terrain (so less than 100ha) 1194Mw, cost 7 billion (with huge delays)

In order to match the power output of seabrook with thermal solar power, you would need three thermal solar plants the size of ivanpah.

With 3 ivanpah, you'll use 4260 Ha of terrain, 6.6 billion in construction costs, for 1131 Mw of net power.

Vs

Seabrook power plant : 100 Ha (42 times smaller) for 7 billion - 1194Mw of power.

So yeah, power density will soon become a quite important issue (especially if you live in small countries.)

And we are still using cars using fossil fuels - imagine the electric consumption skyrocketing if everyone starts using electric cars (you'll need power plants to charge those cars)

(Besides, power density is also becoming an important problem for batteries too - we need batteries capable of lasting longer and longer in smaller footprints)

Edited October 13, 2015 by sgt_flyer

[NuclearNut]

-snip-

In reality - it's nowhere not enough in terms of power density. (And it's not that cheap regardless of incentives)

Here's a quick comparison, between the ivanpah solar thermal power facility (and those mirrors needs much less rare earth than solar panels) (377Mw net power) - terrain size - around 1420 ha (all covered in mirrors) - cost 2.2 billion.

Seabrook nuclear power plant (finished in 1990 with huge delays)the whole power plant roughly fits in a 1 by 1 km terrain (so less than 100ha) 1194Mw, cost 7 billion (with huge delays)

In order to match the power output of seabrook with thermal solar power, you would need three thermal solar plants the size of ivanpah.

With 3 ivanpah, you'll use 4260 Ha of terrain, 6.6 billion in construction costs, for 1131 Mw of net power.

Vs

Seabrook power plant : 100 Ha (42 times smaller) for 7 billion - 1194Mw of power.

So yeah, power density will soon become a quite important issue (especially if you live in small countries.)

And we are still using cars using fossil fuels - imagine the electric consumption skyrocketing if everyone starts using electric cars (you'll need power plants to charge those cars)

(Besides, power density is also becoming an important problem for batteries too - we need batteries capable of lasting longer and longer in smaller footprints)

Actually it gets even more complex than that. The facility has a capacity factor of 31%, whereas the reactor has a capacity factor of around 90%, that means that, charitably, you should need 2.9 megawatts installed capacity to equal one megawatt installed capacity for nuclear energy. So that works out to around 8.7 of said solar farms for one reactor. That would take up arround 34 703 Ha covered in mirrors.

But wait, there's more. The lifetime of that reactor is, without extensions (most reactors receive extensions) 40 years. The solar plant will only last twenty. So that means you need, over the entire lifetime of the reactor, 8.7x2=17.4 solar farms for one reactor, or in other words, 38.28 billion dollars for your solar farm and required replacements to 7 billion for your nuclear reactor. Now mind, this is ignoring Operating and Maintenance (O&M) costs, which in this case go in the favor of nuclear power rather than solar.

[Elthy]

Dont forget the decommision costs...

For the 16 reactors on germany the companys have saved about 40 billion Euros, which is enough for the costs of deconstruction and storage of radioactive stuff, if the costs are calculated optimistic and there are no delays/unexpecedt expenses. But i cant remember any goverment project in the last years that didnt overuse its budget by at least 100%, and here we have to deal with something never done (storing stuff safe for millions of years)...