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China is now leading our clean energy future. Here is an actual link for that, and related ones:

China spending US$3.3 billion on molten salt nuclear reactors ...
SINAP T-MSR Promotional Video
Why China’s 600 fte MSR program wants to cooperate ...

It should be mentioned that China's efforts stem from Kirk Sorensen's rediscovery and publication of the brilliant MSR work done at ORNL many decades ago, which was foolishly cancelled and lost in obscurity. He has since founded a company to further that work in the US, and there is a good overview of the vision here:

The Flibe Energy LFTR49: the triple ace in nuclear GEN IV design

A molten salt waste burner doesn't produce Thallium

And as Wikpedia puts it

https://en.wikipedia.org/wiki/...

Thorium-cycle fuels produce hard gamma emissions, which damage electronics, limiting their use in bombs. U-232 cannot be chemically separated from U-233 from used nuclear fuel; however, chemical separation of thorium from uranium removes the decay product Th-228 and the radiation from the rest of the decay chain, which gradually build up as Th-228 reaccumulates. The contamination could also be avoided by using a molten-salt breeder reactor and separating the Pa-233 before it decays into U-233.

Kirk Sorenson, who is a big LFTR proponent, agrees

http://energyfromthorium.com/2...

Once it turns into Pa-233, the absorption cross-section is still over 5 times greater than the Th-232. That is one of the basic reasons why it's so important to isolate the Pa-233 from the blanket-in order to prevent another neutron absorption. This is a key step that you just can't do in a solid-core reactor that's trying to "burn" thorium (and achieve a conversion ratio of > 1.0).

Finally, the Pa-233 decays to U-233 in 27 days. The U-233 has a huge cross-section, mostly for fission (531 barns) but with a lot of absorption (45 barns). Thus, uranium-233 left in the blanket will really want to gobble up blanket neutrons and cause fission. That leads to even more trouble, because that will deposit fission products in the blanket, complicating reprocessing and making the blanket "hot" with radiation from fission products.

All of these factors argue for getting protactinium of out the blanket and letting it decay to U-233 outside of the neutron flux. The U-233 can then be removed by fluorination to UF6 and adding it back to the core salt by reduction to UF4. Continuous refueling of the core means that excess reactivity in the core can be held to almost nothing, an extremely important consideration for safe operation that is very difficult to achieve in a solid-core reactor.

I.e. LFTRs are the sollution to the Thallium problem you'd get in a solid fuelled Thorium cycle reactor. However I don't really know enough about this to be able to comment further.

Still I'd support funding into research into LFTRs and molten salt waste burners and then see what the result is. Maybe they're something which could be used industrially and maybe they're not.

Same with fusion and things like travelling wave reactors really - at this point it seems like it's promising enough to do research now and hope to deploy it in a few decades. It might not work out, but it seems to be promising enough to be worth funding research in. Maybe it will pay off, maybe it won't. Fund enough advanced reactors simultaneously and you're bound to get lucky with one or more of them. A lot of the funding is coming from the private sector anyway - it doesn't need to be all public.

Once you have some nuclear power plants to stop the CO2 released from coal then use some of that nuclear power to mine and pulverize basalt rock as fertilizer for crops.

http://www.energyfromthorium.c...

Once spread on the fields the calcium oxide, or lime, in basalt will react with the CO2 in the soil to reduce the acidity. Farmers already lime their fields, only now it's produced from mining limestone and then cooking off the CO2 to produce lime. Any CO2 this takes from the soil will only counteract what was released in the lime kilns. It does nothing for the CO2 released from the fuel burned in the kilns. Any CO2 taken from the soil will mean reducing CO2 in the air since natural processes, such as the rain, will carry the CO2 out of the air into the soil where the lime can trap it chemically as limestone, or CaCO3.

There are other uses for the lime and sand from the mined basalt, like making cement and glass. Using nuclear power is an important aspect of this plan since this is an energy intensive process that would have to operate in the mines. They'll have to mine where the rock is easy to reach, not where the sun shines and wind blows. They may be far from infrastructure, making running power lines impractical.

Farmers need to replace this lime in the fields continuously as the nutrients are taken up in the crops and as rains wash it away, so it's not like they spread it out once and the acidity problem is fixed. There is an incredible amount of basalt on Earth, we just will not run out.

Yes !
and as I said, the chemical processing plant that purifies the core on line is outside the containment, as well as exchangers, and so on.

http://energyfromthorium.com/w...

If nuclear policy had favored the sane approach, opposition would have had much less to work with. Scaling up a submarine reactor was a terrible idea, and the accident scenarios that have since played out were forewarned. When the inventor of the technology is firmly opposed, and advancing another option, a sensible person might give it some thought. Instead they fired Alvin Weinberg, for daring to voice safety concerns. Fortunately, even if nuclear technology is 50 years behind, it is still the most capable low-carbon energy source, and also the one with the greatest realizable potential for improvement.

While nuclear started off on the wrong foot, the larger problem was that it was facing very powerful entrenched interests. Along with the obvious measures to shape public opinion and policy, they also sponsored the dishonest "research" that formed the basis of nuclear regulation which persists today. They even funded early “environmental” organizations, to embed an anti-nuclear tenet at the core of “green” values, which sadly still takes precedence over decarbonization.

Driverless cars will face much less opposition though, since they are competing with people and displacing jobs. Great for owners of large businesses involving transportation and such. Good for everyone else too, but the ever increasing scarcity of productive jobs needs addressing. The gains of productivity should benefit everyone, not just a handful of owners. It is also crucial to keep in mind that while energy is the foundation of all prosperity, it will never again be a high-margin product and so offers little incentive to invest in production of it. That also needs to change, even if it means diverting a massive chunk of the defense budget to building reactors. Interestingly, that would be a much better return on investment for national security as well.

Opposed Piston Opposed Cylinder engines have two pairs of pistons facing one another, each in a cylinder on opposite sides of the crankshaft. There is no cylinder head, just a ring of ports for intake and exhaust in the cylinder walls near where the pistons bottom out. With a slight timing offset, the exhaust ports will open before the intake ports. It is a fascinating design, simple and elegant, with very few moving parts and a high power density. The engine is completely balanced, and all of the linear forces cancel, leaving little load on the bearings, just torque. There are other interesting concepts out there, but this one is actually being mass produced today.

Electric cars are certainly attractive, but the reality is that hydrocarbon fuels are going nowhere. The energy density and flexibility are simply too great, and we have an immense amount of infrastructure and equipment that make use of them. The fastest way to a greener world isn't through electric cars, but rather synthetic carbon-neutral fuels, which can be efficiently produced using heat from nuclear reactors. Nuclear Ammonia is particularly interesting, because the feedstocks are readily available from air and water. Other replacement fuels can also be synthesized, but extracting carbon from air or water will add to the cost.

The navy has demonstrated technology to create fuel from seawater. This is a carbon neutral process that can be performed on site with clean nuclear electricity, rather than razing forests and shipping them across the sea. None of the "biofuels" in common use are remotely friendly to the environment.

Waste heat from nuclear reactors can also be used to desalinate seawater, or produce synthetic fuels and fertilizer.

Some rebuttals are in order, because otherwise people might think it's actually all valid, while, in fact, most is not.

Rebuttals:

http://pche-sts.blogspot.be/20...

http://energyfromthorium.com/2...

Many of those counter-arguments you raise, have been brought up before, and equally as much has it been shown to be largely complete nonsense.

Rebuttals:

http://pche-sts.blogspot.be/20...

http://energyfromthorium.com/2...

Many of those counter-arguments in that slasdot-post you link to, have been brought up before, and equally as much has it been shown to be largely complete nonsense.

Hydrogen from natural gas is combined with atmospheric nitrogen to produce ammonia for fertilizer. Ammonia production alone consumes more than 1% of all primary energy, so it is indeed a concern.

However, the hydrogen need not come from natural gas. Water can be dissociated using nuclear heat or electricity. See more about Nuclear Ammonia, for a sustainable and efficient alternative. (The hydrogen can also be used to create other cost competitive synthetic fuels, which could displace fossil fuels entirely for transportation.)

Sadly, most "environmentalists" would prefer that we starve to death rather than embrace a technology capable of bringing prosperity to all of humanity with a minimal environmental footprint.

Here: http://energyfromthorium.com/

A nuclear engineer friend of mine explains that investment in such beneficial technologies is hampered by legitimate fears that new projects will be shut down due to irrational, fear-based regulatory policy.

No I don't work with anything nuclear. I'm a computer / telecoms guy.
But I did studied this stuff in deep enough detail to understand why it should work. And they guys proposing it are surprisingly open, even having in depth forum discussions at http://energyfromthorium.com/f.... Come read up on the posts, understand the data. Its a lot more logical than trying to power Germany with solar+wind in the winter.

I see you have both radiophobia and nuclear lies being fed to you. I suggest you open your mind to the nuclear world.
You might want to start with: http://energyfromthorium.com/f...
The smallest nuclear reactor proposed is 50MWt in size, about 20x too powerfull for a locomotive (1-2 MWt scale), 100x larger than a truck engine (200KWt scale).
The smallest scale transportation where nuclear reactors would make some sense would be large ships. Anything less would be foolish.
Just because someone says something it doesn't mean it makes sense.
I believe in electric vehicles, charged mostly with 11PM-5AM cheap electricity.
But hydrogen fuel cells could make sense for larger vehicles, that would require a very large battery, where having a large hydrogen tank would work better ($$$) instead.
But currently hydrogen is being produced from natural gas. So its still CO2 producing.
The only economical large scale hydrogen production solution is actually high temperature nuclear reactors, like Molten Salt reactors that are able to sustain 700-800C operation due to the nuclear fuel being molten in the primary coolant, avoiding any meltdown risks. Typical nuclear reactors use solid fuels where the nuclear fuel runs around 1800C, and goes through very steep temperature gradients until hitting the coolant @ 280-350C, creating meltdown risks.

Not to mention the thousands of tons of Thorium they buried in Nevada because they didn't have any use for it.

Bingo!

Not to mention the thousands of tons of Thorium they buried in Nevada because they didn't have any use for it.

A becquerel is one disintegration per second, so it is a unit of atomic scale; of course numbers will be big and scary. For perspective, let us consider mercury on the atomic scale. This will be a comparison of atoms to atoms, the rate of radioactive atoms decaying, vs the rate of mercury atoms being released into our environment by burning coal.

We are burning 7 billion tons of coal, releasing 910 tons of mercury into our environment each year. A mercury atom has a mass of 200.6 u or 3.331e-25 kg, which divides to 2.732e30 atoms per year, or 8.657e22 atoms per second. That is 86570 billion billion "becquerels" of mercury, and that isn't even considering the thousands upon thousands of tons of other highly toxic materials also released.

Remember, radioactive atoms are disappearing, while the mercury atoms are everlasting. Mercury which was bio-concentrated millions of years ago, and we will now have the opportunity to do it once more after re-releasing it.

That coal should be left in the ground, and not foolishly burned for energy. It is criminal to turn such a valuable concentrated carbon resource into ash, particulate, and CO2 and disperse it into our environment. Incidentally, there is more than 10 times the energy recoverable from the traces of uranium and thorium within the coal, than from combusting the coal itself. Of course, that isn't available if we mix the ash into sidewalks and roads, and such. (and it still contains some of the other nasties which didn't make it into our air or water already.)

The point is that there will never be "enough" coal if we continue using it as an energy source. It might last for a while, but conservation is still not sustainable. Conservation will only drive up prices for energy and preclude using it for energy intensive processes like recycling. Even producing the steel, concrete, and rare earths necessary for renewables is highly energy intensive and entirely dependent upon heat from fossil fuels today. Those renewables are also exposed to the elements and need to be recycled every decade or two. We are already reverting to burning trees, and it is only going to get worse until more people accept that nuclear power.

Anyway the crucial point is that nuclear provides reliable energy 24/7 through severe weather or natural disasters and with a minimal environmental footprint. They are among the most robust structures in existence, and molten salt reactors would be even more resistant to damage. (Granted, the transmission infrastructure is still vulnerable, and that is another reason why it should be minimized.) Even coal and natural gas plants can be taken off line by severe weather. During the recent polar vortex, it was nuclear which kept the lights on in New England.

Some of it may be scrubbed, but there are still significant losses. Even a small fraction of a percent escaping results in substantial pollution when burning billions of tons of coal a year. Have a look at the contents, and that isn't even considering the contribution of CO2 to ocean acidification.

Germany should reverse course, as they are not on a path which will eliminate or even mitigate coal pollution. Current policy is driving prices up and creating a permanent dependence on fossil fuels to compensate for unreliable energy from wind and solar. A $100B spent on nuclear instead would have been a much wiser investment.

Producing ammonia today consumes more than 1% of all man-made power, and natural gas is used as a source of hydrogen. Like hydrogen, it is an energy carrier and not a energy source. That considered, ammonia produced with nuclear heat would be an excellent carbon neutral liquid fuel, and is expected to cost significantly less than gasoline.

The MSRE cleanup became expensive because it was left alone for decades. Should the cleanup have been done up to 10 years after its shutdown, it would have costed a few % of that.
No, I'm not an ignorant fanboy. I'm no nuclear engineer, but I have an introduction to nuclear technology course with an A+ grade to show for it.
Most of the price tags associated with anything nuclear the DoE comes up with is always outrageously expensive. Its the result of doing everything in the cost is no object + pork barrel model.
You guys never show up at thorium discussion forums.
Your arguments will be ripped to pieces in front of the nuclear PhDs working on this. You should try this once:
    http://energyfromthorium.com/f...

It would not be a subsidy. The Nuclear Waste Fund has accumulated a balance of $25 billion dollars, paid in fees over the years by nuclear plant operators. The parent is only suggesting that it be spent on developing the technology which has the greatest potential for managing the "waste", rather than waiting it out. In the end, those are the only two options: fission it, or bury it.

Nuclear "waste" and "spent fuel" are misnomers, as conventional reactors extract less than 1% of the energy from mined uranium. It is insane to treat it as waste, when the technology exists to completely transform the remainder into energy, while eliminating virtually all of the long term radioactivity. The technology was proven decades ago, and the remaining development and commercialization could be completed using a small fraction of the available fund.

Molten salt reactors like LFTR would not only produce enormous amounts of electricity from that "waste", but also valuable medical isotopes, radioisotopic fuel for space probes, and rare earths. As a high temperature reactor, even the rejected "waste" heat has many potential uses, including desalination and producing ammonia or other synthetic liquid fuels. Another interesting application is carbon neutral cement.

Discouraging development of nuclear not only prevents safer designs and a solution for the waste issue, but also assures continuing dependence on fossil fuels in the many cases for which renewables are not suitable. (Including the production of more renewables, which require a whole lot of steel and concrete. Or to provide energy while the wind and sun are unavailable.)

It would not be a subsidy. The Nuclear Waste Fund has accumulated a balance of $25 billion dollars, paid in fees over the years by nuclear plant operators. The parent is only suggesting that it be spent on developing the technology which has the greatest potential for managing the "waste", rather than waiting it out. In the end, those are the only two options: fission it, or bury it.

Nuclear "waste" and "spent fuel" are misnomers, as conventional reactors extract less than 1% of the energy from mined uranium. It is insane to treat it as waste, when the technology exists to completely transform the remainder into energy, while eliminating virtually all of the long term radioactivity. The technology was proven decades ago, and the remaining development and commercialization could be completed using a small fraction of the available fund.

Molten salt reactors like LFTR would not only produce enormous amounts of electricity from that "waste", but also valuable medical isotopes, radioisotopic fuel for space probes, and rare earths. As a high temperature reactor, even the rejected "waste" heat has many potential uses, including desalination and producing ammonia or other synthetic liquid fuels. Another interesting application is carbon neutral cement.

Discouraging development of nuclear not only prevents safer designs and a solution for the waste issue, but also assures continuing dependence on fossil fuels in the many cases for which renewables are not suitable. (Including the production of more renewables, which require a whole lot of steel and concrete. Or to provide energy while the wind and sun are unavailable.)

Why not clean energy?

http://energyfromthorium.com/2...

Oh well, I guess we'll just have to buy it from this guy:

http://www.itheo.org/bill-gate...

Solar versus nuclear: a question of scale. Further comments go into detail about resources and areas.

Read about Germany for an idea of what $50 billion will buy in terms of renewables--that is a drop in the bucket of their expenditures. Despite having been at it for more than a decade, they have little to show for it except skyrocketing electricity prices. Replacing fossil fuels with solar is an expensive fantasy.

Molten Salt Critical Reactors for the Transmutation of Transuranics and Fission Products

Thus, at a power density of 10 kW/cm3 the effective half life of 126Sn, 90Sr, 137CS and 79Se is, approximately, 30, 9, 4 and 2 years

Getting better, since you can burn the FPs rather than trying to sell them off for chemo. This also gives you something to do with the people screaming, "Plutonium!"

Westinghouse Nuclear and the other vendor (GE? I don't recall) make a lot of money making fuel rods. It may not be that much compared to the cost of building the plant, but it's a very significant motivator for them to lobby against any other system.

I'd like your take on Kirk Sorenson's paperwork advocating LTFRs - from memory, Energy from Thorium and FLiBe Energy. He seems to be the most active proponent in the US of Thorium based MSRs. He and other advocates argue that because of the major differences in the entire system technology (not least the difference in proliferation risk), it would not be necessary to build Gigawatt scale reactors - instead they could be scaled to neighborhoods.

It's only an indicator not proof of anything, but IIRC the MSR run at Oak Ridge was a 10 MW reactor (the electricity produced was just sent to big resistors outside), fit into a single room, and was turned off every night and on in the morning. I think they were not using Thorium - it's been a year or so since I explored any of this and I'm too lazy/busy to retrace my steps.

Complete combustion of 1 short ton (2,000 pounds) of this coal will generate about 5,720 pounds (2.86 short tons) of carbon dioxide.

That means we're looking at dealing with 1 billion * 2.86 short tons = 2.86 billion short tons = 5,720,000,000,000 (or 5.72 trillion) pounds of CO2 per year. My calculator suggests that's around 497,000x the mass of the potential nuclear waste, not to mention more radioactive waste actually in the atmosphere. Do you really want to discuss which of these methods is contributing more radiation to the atmosphere and whose house all these byproducts are polluting? I'm pretty sure they don't usually entomb the resultant CO2 in concrete, even if half of (less than half, actually) fly ash winds up that way.

The energy density of coal pales in comparison to thorium:

At these prices the value of the energy produced by the thorium is an average cubic meter of the Earth’s crust in a LFTR is worth (11000 to 17000)/(220) = 50 to 77 cubic meters of anthracite coal.

At this point, NIMBY is just mindless obstructionism. There is no scientific ground left to stand on, unless you happen to have an actual, implementable solution for long-term base power, and no, solar isn't cutting it. For that, you have toxic build and recycling processes, short life, low efficiency, the sort of thing that's okay on a small scale but hasn't shown real base-load promise due to the cost of storing energy en-masse for use during off-peak hours instead of throttling a nuclear reaction pulling energy from a very dense storage medium.

LFTR isn't just some pie-in-the-sky. It's a tried and tested reactor design, and we learned from our initial failures (metal embrittlement, evolution of uranium and plutionium), and we came out the other side with a new process for decommissioning. This is how science and engineering work, folks.

I'm sorry you took it that way, I was rather hoping that you would read it and develop an appreciation of how fluid fueled reactors are utterly different and fundamentally superior. Then, hopefully discontinue suggesting that people "educate" themselves with the typical anti-nuclear/thorium propaganda. While your links do not have tailored rebuttals yet, I expect that all of the various specious arguments are addressed within, repeatedly.

For an actual education, I would suggest starting at Energy from Thorium, or the forum if you have technical questions.

I'm sorry you took it that way, I was rather hoping that you would read it and develop an appreciation of how fluid fueled reactors are utterly different and fundamentally superior. Then, hopefully discontinue suggesting that people "educate" themselves with the typical anti-nuclear/thorium propaganda. While your links do not have tailored rebuttals yet, I expect that all of the various specious arguments are addressed within, repeatedly.

For an actual education, I would suggest starting at Energy from Thorium, or the forum if you have technical questions.

Thorium should have been the mainstream Nuclear solution long ago:
Kirk Sorensen has been a huge proponent of this.
http://energyfromthorium.com/
5 min version: https://www.youtube.com/watch?v=uK367T7h6ZY
97min version: https://www.youtube.com/watch?v=D3rL08J7fDA

Interestingly, the Thorium in the coal would provide 10 times the energy relative to burning the burning the coal itself. The Uranium could also provide an additional 4 times the energy if fissioned in an efficient reactor. Molten salt reactors like LFTR make these efficiencies possible.

So, we are extracting about 1/15th of the energy content, poisoning our environment and food, and turning some of the waste into concrete is supposed to make it acceptable? CO2 is itself a huge problem, but there is also a lot of other nasty stuff in coal as well. Particulate emissions alone kill about a million people every year, to say nothing of mining, poisonous fish, and ocean acidification which threatens mass extinctions which will leave little but jellyfish.

We desperately need to stop burning coal.

Such a simple solution.

Liquid Fluoride Thorium Reactor

Has passive safeties, does not use water to cool, heats up gas to generate power.

https://en.wikipedia.org/wiki/LFTR
http://energyfromthorium.com/

However, the carbon moderator core at over 600 C scares me. What if oxygen gets in there? Burning core, reminscent of Chernobyl. Very scary.

Contrary to what you might think, carbon is actually safer at those temperatures. Under neutron bombardment at low temperatures, the Wigner energy can build up, and that is the source of the problems. However, at the operating temperatures of molten salt reactors, solid graphite is quite safe. (You can purchase graphite crucibles good to 2500C.) There is further discussion here.

I don't understand why this Closed Cycle Brayton will work with a Thorium plant but not with a conventional nuke plant. So it would seem either that [1] a conventional plant will have the advantage of not needing water as well, or it would be cheaper or more efficient to [2] make a Thorium plant use cooling water and thus as likely they will have it.

Very insightful, pointing out the difference between use of water in the reactor and water used for (conductive) cooling. At the moment the word 'conventional' implies the use of solid fuel and a loop of water inside the reactor for moderation and cooling, and the use of phase transition (water to steam then back to water again) to drive turbines.

[1] Brayton would work with a Pebble Bed Reactor where the solid fuel is encased spherical 'pebbles' of graphite moderator and inert gas such as helium is used for cooling. There is no phase change, the helium remains a gas which varies in temperature.

One such experiment was the THTR-300 breeder in Germany, which attempted to leverage the pebble concept into reality and managed to do so from 1985-1988, despite some problems managing the solid fuel. It was not a proving ground for Brayton though, the helium was used to heat water in a Rankine (steam) cycle.

Pebble Bed Reactor designs are also considered to be "walk away safe" despite these problems. The danger of graphite igniting if the reactor is breached and the helium replaced by air seems to be overstated, but there does remain the possibility of ignition if it is reduced to dust (such as in a steam explosion, as happened at Chernobyl) or if it comes into direct contact with the solid fuel at the center of the pebble.

So both 'conventional' rod-and-pellet and Pebble Reactor manufactured pebbles both share one important characteristic --- the necessity of an extremely critical solid-fuel manufacturing process where a failure of workmanship has undesirable results.

But I wonder though as a layman (disclaimer!) if there is at least one major unresolvable problem with the pebble concept --- and that is how could you be confident you could take the reactor below critical in the presence of multiple mechanical failures? As compared to the salt concept where gravity alone drains the fissile salts out of reach of the graphite moderators with sub-criticality greatly assured.

[2] Though your biggest safety win arises from removing all water from within the reactor and its containment building, the power plant itself could employ water to assist in cooling. In coastal areas LFTR waste heat is envisioned to assist in desalinization.

Sorensen discusses the prospect of substituting a Brayton for a 'conventional' Rakine steam reactor here, citing concerns of efficiency and operating temperature where the heat necessary to drive Brayton places 'conventional' solid fuel configurations in jeopardy of melting.

You dismiss the presenter as a talking head - I think he deserves a little more respect as he does have meaningful credentials. His name is Kirk Sorensen, and wikipedia says he "... has a bachelor's degree in mechanical engineering from Utah State University, a master's degree in aerospace engineering from the Georgia Institute of Technology, and is currently pursuing a master's degree in nuclear engineering at the University of Tennessee. He worked at NASA's Marshall Space Flight Center from 2000 to 2010, followed by a year at Teledyne Brown Engineering in Huntsville, Alabama as Chief Nuclear Technologist until he left to found Flibe Energy in 2011."

IIRC, he was tasked with designing a moon colony for NASA and had to come up with a power source capable of operating safely within the confines of a small community and with limited refueling/interaction. That's where his version of the LFTR came from.

You may have missed one or two of the main technical points of this setup.

1) The reactor is fueled and 'waste' is extracted continuously using already well-understood chemistry - no fueling downtime.
2) The LFTR can burn our current nuclear waste ridding us of the nasty actinides that make the current 'waste' dangerous for long periods of time.
3) It can also burn the 'Killstoff' of which we now have an overabundance
4) Many of the extracted 'waste' products from the LFTR are actually useful metals/isotopes - medical isotopes, isotopes for RTGs, etc.

Also, a word on 'forever' - yes, he may have been using a bit of hyperbole, but as compared to other non-solar-derived energy sources, 'forever' may actually be close to the correct word.

Energy from Thorium states that "A mere 6,600 tonnes of thorium could provide the energy equivalent of the combined [annual] global consumption of 5 billion tonnes of coal, 31 billion barrels of oil, 3 trillion cubic meters of natural gas, and 65,000 tonnes of uranium. With LFTR, a handful of thorium can supply an individual’s lifetime energy needs; a grain silo full could power North America for a year; and known thorium reserves could power advanced society for many thousands of years."

According to estimates, there are somewhere between 1.9 and 2.8 million tonnes of Thorium economically available right now - that's economically available with no use whatsoever for Thorium! The total crustal Thorium content is estimated at 120 trillion tonnes.

From the same article:

In event of a thorium fuel cycle, Conway granite with 56 (+-6) parts per million thorium could provide a major low-grade resource; a 307 sq mile (795 sq km) "main mass" in New Hampshire is estimated to contain over three million metric tons per 100 feet (30 m) of depth (i.e. 1 kg thorium in eight cubic metres of rock), of which two-thirds is "readily leachable". Even common granite rock with 13 PPM thorium concentration (just twice the crustal average, along with 4 ppm uranium) contains potential nuclear energy equivalent to 50 times the entire rock's mass in coal, although there is no incentive to resort to such very low-grade deposits so long as much higher-grade deposits remain available and cheaper to extract. Thorium has been produced in excess of demand from the refining of rare earth elements.

So if we were to start actually having a use for Thorium, chewing up plain old granite would yield 50x the energy of coal. If we could only tap 10% of the crustal supply, we'd have a 1.8 billion year total energy consumption supply (not just electricity) at current consumption. As far as societies and species go, that may as well be forever.

Perhaps you should read about the Windscale fire:

During the accident, uranium fuel caught fire — not the graphite moderator as is widely assumed.

There is a discussion of graphite fire risk here, and the specific circumstances which can cause problems for graphite are not present in a LFTR.

Tell that to the people directly involved with Chernobyl. You seem to have forgotten some basic chemistry, that is reaction rates, and even what reactions happens, are temperature dependent.

No concern to you, is not the same as not a concern. These concerns where raised/pointed out in scientific papers on LFTR.

Here you go. For various reasons, it is not a concern in a LFTR.

Still, there is still no graphite present in the drain tanks, so it is largely academic.

Fukushima's problem was caused by flooding in the basement where diesel generators were.

Not according to Kirk Sorensen, a nuclear technologist who operates the site energyfromthorium.com who for Forbes wrote the article Explainer: What Caused The Incident At Fukushima-Daiichi. At first he writes "The tsunami destroyed the diesel generators that provide power to drive the pumps that circulate the water coolant through the reactor that removes decay heat." But a bit later he writes generators ran "until their day tanks emptied" of diesel fuel. If emergency generators were running then they could have been refueled. The hard part would of been finding the people who were willing to put their lives at risk. However anyone who supports nuclear power should be so willing, if they aren't willing to put their own lives at risk why do they support putting other people's lives at risk?

All of the mentioned things could potentially cause enough problems in nuclear plants, but they would need to huge (like >7.75 magnitude earthquake *directly* under the reactor)

The title of the article Earthquake threat to nuclear reactors far higher than realized sums it up pretty well. Risk from earthquake is up to 24 tymes higher than previously thought.

people should be smart enough to shutdown the reactor & do other preparations in time as hurricanes can be detected way earlier than tsunamis/earthquakes.

And what of tornadoes? They aren't as predicable as hurricanes. And at specific points they strike they are more powerful than hurricanes.

The biggest reason I oppose nuclear power though is because nuclear power is Hooked on Subsidies
"How do France (and India, China and Russia) build cost-effective nuclear power plants? They don’t. Governmental officials in those countries, not private investors, decide what is built. Nuclear power appeals to state planners, not market actors."

If all energy subsidies were dropped, including for fossil fuels and nuclear power then geothermal, solar, wind, and other clean(er) energy sources would be more cost competitive. Coal get tens of billions of dollars in subsidies. Without government loan guaranties Wall Street would not finance nuclear power. And if fossil fuels had to pay all of it's costs, instead of passing on external cost to others, their cost would be higher.

Falcon

If we converted all of our nuclear sites to run on Thorium it would become a non-issue. Nuclear energy could be clean and safe but it would be harder to make atomic weapons.

http://energyfromthorium.com/

I'm surprised no one seems to have mentioned this, but we ran a very safe (for the time) molten-salt reactor, AKA the LFTR (liquid fluoride thorium reactor). Later, total decommisioning was found to be an issue, but we've done what scientists and engineers do: find solutions. From Wiki: "Much of the high cost was caused by the unpleasant surprise of fluorine and uranium hexafluoride evolution from cold fuel salt in storage that ORNL did not defuel and store correctly, but this has now been taken into consideration in MSR design.[22]"

Nuclear is here to stay, in one form or another, unless humans cease to exist. Note that I didn't say "cease to exist tomorrow or next week." Try to think long-term. If you still can't wrap your head around the idea that nothing in the universe comes for free, and that we are stuck on a very small rock, your Buxton Index might not be the same as mine.

That's wonderful toy but still a toy.
If you read the history of its decommissioning, you'll find it was no easy task. Not insurmountable problems but not trivial either.

The reason that the decommissioning was such a mess, is that it was delayed for decades. It was known at the time that this would cause problems down the line, yet those responsible for canceling the project decided to let it sit rather than processing the salts--something which was proposed and would have been trivial at the time.

The earliest you could hope to see thorium reactors would be the mid-2020s if everything went well.

That's a long time to wait for the power of radioactive unicorn farts - we need to act NOW ( actually 10 yrs ago but water under the bridge and all that )

Let's hope it doesn't get pushed back any further, because we have no replacement. We do need to act now, but we need to act responsibly, not pour money into non-solutions like wind and solar. (They have their niches, but are far from a comprehensive energy solution.) As much as people would like to simply wish it or legislate it into existence NOW, the physics/economics simply don't work, no matter how we try to force it with subsidies.

The enemy is coal, and to a lesser extent the other fossil fuels. The only way to displace coal on any significant scale is with a technology that provides cheaper energy--and several studies have shown that molten salt thorium reactors have the potential to do so. See Thorium: energy cheaper than coal.

People in the developed world are willing to sacrifice and accept that renewables will be more expensive, but there are billions more people in places like China and India who are desperately trying to raise their standard of living, and they simply can't afford it. Realistically speaking, neither can we, but the costs of renewables are well hidden and people don't appreciate just how untenable the proposition really is.

Conventional nuclear and natural gas could provide an interim solution, but as long as people continue to embrace the delusion that renewables are going to magically fix the problem, we are merely postponing an inevitable catastrophe.

http://www.energyfromthorium.com/

IANA Nuke-E, but I think you're thinking of Thorium 233, which has a half-life of 22min.

Thorium absorbs a neutron and becomes Th233, which decays in (half-life) 22 minutes to Protactinium-233, which has a half-life of 27 days and decays to to U233. Meanwhile, if your Th233 takes another neutron during its 22min half-life, that is what will decay into U232 over time.

The trick to getting "clean" U233, uncontaminated by U232, is to isolate the Pa233 and let it decay outside of the neutron flux. Unfortunately this is also probably a necessary step in getting LFTR to work, as explained in this note by one of its most well-known proponents. I call this "unfortunate" because it would seem to negate one of the key arguments in favor of LFTR (and Thorium in general), that it is resistant to proliferation due to "inevitable" U232 contamination. Obviously if your design calls for isolating Pa233 in order to produce pure U233, then you can't also claim that your "dirty" U233 is unsuitable for weapons.

Personally I think the risk is still acceptable (I'm a strong supporter of Thorium-cycle nukes), but this contradiction will have to be addressed eventually.

Supposedly one that does not kill us. "Better" is not just a matter of engineering; it's about having the basic sense not to do anything that will render our habitat useless.

A better nuclear-plant like a thorium reactor does not go critical. It does not risk the same problems as the old reactors that where built during the 50-80'ies.. The problem with nuclear power is not safety, it's the inability for people to accept development of them since they think all nuclear devices are harmful without actually having an idea of what is safe or not and this is causing the politicians to stop accepting new, safer, reactors to be built and we are stuck with the old ones since we still need the power from them...

Even if a dam breaks and thousands die, the land itself can be used again somehow. Contrary to that, Chernobyl (and most surely Fukushima) are off limits to mankind now.

And what happens with farm-land when a dam breaks... top-soil gets washed away, houses demolished, peopled killed.
- Power to rebuild the houses.
- Power to transport new top-soil back to the farm-land..

With Chernobyl it was gross human error that caused the tragedy.. Turning off the safety systems and pushing the stuff well pasts it's limits is not safe...
People have already started to move back to the surrounding areas that has dropped to safe levels... The actual Chernobyl plant will probably be unsafe for some time (300-600 years).. But this accident was due to grossly incompetent people and a plant that was not maintained as it should..

Even if you burn something, it is possible to devise a close cycle where you plant, absorb CO2 and then release it again by burning wood, which is far better than just burning oil or dealing with the uncontrollable: radioactive reactors.

The problem is that we could never grow enough trees to facilitate the energy-demands... But the biggest parts to make something like that sustainable..
- Fuel for the machines and trucks for chop the trees down, transport to the plant and then transport the ashes away from the plant..
- Risks for the workers.. People in this line of work today have quite high injury/death rates.

Death-rates by energy-source: http://nextbigfuture.com/2011/03/deaths-per-twh-by-energy-source.html
Some information about thorium reactors: http://theweek.com/article/index/213611/could-thorium-make-nuclear-power-safe

The pro about a thorium reactor is that as soon as you stop the proton beam it will stop power-generation.. Ie, it cannot go into a melt-down state... http://energyfromthorium.com/lftradsrisks.html

Agriculture need not be based on petroleum.

Speaking of thorium. http://energyfromthorium.com/2011/03/10/free-thorium/

"Its a nice rosy thought but we really don't have the unlimited energy you speak of; or if we do we haven't the ability to transport it where we need it and concentrate it enough for many of the applications our society has come to depend on."

"GE: Solar Power Cheaper than Fossil Fuels in 5 years"
http://cleantechnica.com/2011/05/29/ge-solar-power-cheaper-than-fossil-fuels-in-5-years/

Also, maybe:
"NASA seriously believes in Low Energy Nuclear Reactions (LENR)"
http://mnispel.net/neengineer/?p=320
http://freerepublic.com/focus/f-bloggers/2832338/posts

And:
http://energyfromthorium.com/

And there are others. Energy is not a big issue if we want to solve that. Lack of imagination, will, and social consensus is more of the problem:
http://www.juliansimon.com/writings/Ultimate_Resource/

As well as the diversion of most of our resources into guarding, competition, and war...

As to your quote, I answer it with another quote: "The woods would be pretty quiet if no bird sang there but the best." :-)

Also, who is to judge what "best" is?

Clearly, even third rate is soon going to be enough to create WMDs (like the biotech, nanotech, or microrobotic equivalent of what script kiddies do with computers). So, we still need to figure out a way to make a world that works better and better for more and more people (including by reducing violence through healthier nutrition); see for example:
"Omega-3, junk food and the link between violence and what we eat: Research with British and US offenders suggests nutritional deficiencies may play a key role in aggressive behaviour"
http://www.guardian.co.uk/politics/2006/oct/17/prisonsandprobation.ukcrime

Also, if the brains of the masses are dulled in the 21st century, it is in large part because the "best" put in place systems to make them that way through compulsory schooling; see John Taylor Gatto's writings:
http://www.johntaylorgatto.com/chapters/16a.htm
"I'll bring this down to earth. Try to see that an intricately subordinated industrial/commercial system has only limited use for hundreds of millions of self-reliant, resourceful readers and critical thinkers. In an egalitarian, entrepreneurially based economy of confederated families like the one the Amish have or the Mondragon folk in the Basque region of Spain, any number of self-reliant people can be accommodated usefully, but not in a concentrated command-type economy like our own. Where on earth would they fit?"

How much our resources do you think are currently consumed by guarding, competition, and warfare? I'd suggest over 90%... See for example:
http://www.whywork.org/rethinking/whywork/abolition.html
"Only a small and diminishing fraction of work serves any useful purpose independent of the defense and reproduction of the work-system and its political and legal appendages. Twenty years ago, Paul and Percival Goodman estimated that just five percent of the work then being done -- presumably the figure, if accurate, is lower now -- would satisfy our minimal needs for food, clothing and shelter. Theirs was only an educated guess but the main point is quite clear: directly or indirectly, most work serves the unproductive purposes of commerce or social control. Right off the bat we can liberate tens of millions of salesmen, soldiers, managers, cops, stockbrokers, clergymen, bankers, lawyers, teachers, landlords, security guards, ad-men and everyone who works for them. Ther

Yes, it's quite possible. See energyfromthorium.com

arguments I've heard
- never built one to scale
rebuttal - it doesn't matter - build 1000 tiny ones instead if big ones don't work.

- continuous reprocessing has never been tested and may be impossible
rebuttal - you don't know unless you try, and it seems feasible.

- they still spit out the same long half-life, long decay elements as conventional reactors
rebuttal - most of these can be reused or salvaged for medical devices, and it burns 97% of its fuel instead of 3% or less. Also you will find almost as much naturally occurring "waste" where the Thorium came in the first place. Here is a breakdown from http://energyfromthorium.com/lftradsrisks.html :

Additionally, because LFTR burns all of its nuclear fuel, the majority of the waste products (83%) are safe within 10 years, and the remaining waste products (17%) need to be stored in geological isolation for only about 300 years (compared to 10,000 years or more for LWR waste). Additionally, the LFTR can be used to "burn down" waste from an LWR (nearly the entirety of the United States' nuclear waste stockpile) into the standard waste products of an LFTR, so long-term storage of nuclear waste would no longer be needed.

read that again - can be used to "burn down" waste from an LWR - so in addition, we can get rid of a lot of the waste from the inefficient reactors we have.

- they are really Uranium reactors and they require a seed reaction
rebuttal - true reactors like this are Uranium - they convert Thorium to Uranium and then split, however the base fuel is still Thorium and the seed can be reused. It is also possible to continuously feed them if the equipment can filter out impurities. No physical research has been done here.

- Thorium is uneconomic, and costs far more than Uranium
rebuttal - Thorium is much more plentiful than Uranium, easier to mine and therefore if a market emerged, would likely drop from current ~$5000/kg to potentially $10/kg or less. That is compared to enriched Uranium, which is over $1600/kg after an expensive processing and/or reprocessing. Total cost of operations is also much less - estimated at 30-50% of a LWR.

- Thorium is bad for selling weapons grade elements to the government and charging massive reprocessing fees and kickbacks that line the back pockets of reactor owners.
um, exactly.

Remember that game? Surplus energy is critical for supporting innovation within a society, and as some of our energy resources are becoming more expensive to exploit [Peak OIl], surplus energy declines. Apparently per capita energy consumption has declined over the past 40 years, so it seems possible, perhaps likely, that this is having numerous deleterious effects within our society, which are actually symptoms rather than prime causes of our unfortunate situation.

It is a bit late in our game to respond to this old problem (we peaked in our domestic petroleum production back in the 70s), but if we could tap into a vast source of carbon-free energy, we could conceivably synthesize all of the carbon-neutral fuels we require. Now, where is that wonderful machine?

[The game!] http://en.wikipedia.org/wiki/Civilization_(video_game)

[Peak OIl could limit economic growth] http://www.marketoracle.co.uk/Article31330.html

[LFTR] http://energyfromthorium.com/2011/10/04/flibe-uk-4/