Thorium backed as a 'future fuel'

[xchrom]

http://www.bbc.co.uk/news/science-environment-24638816


Nuclear scientists are being urged by the former UN weapons inspector Hans Blix to develop thorium as a new fuel.

Mr Blix says that the radioactive element may prove much safer in reactors than uranium.

It is also more difficult to use thorium for the production of nuclear weapons.

His comments will add to growing levels of interest in thorium, but critics warn that developing new reactors could waste public funds.



***pardon me but...

[DetlefK]

1. Affordable solar in 10 years, fusion-reactors in 30...

And these guys want to go back to nuclear fission?

"I’m a lawyer not a scientist ..." "I am told that thorium will be safer in reactors - and it is almost impossible to make a bomb out of thorium."

He obviously never heard of nuclear waste-management, Fukushima and dirty bombs.

[PamW]

2. Scientist on dirty bombs

Physics Professor Richard Muller of the University of California - Berkeley and author of the book "Physics for Future Presidents", wrote the following article on the subject of the "dirty bomb". Courtesy of MIT and Technology Review, June 23, 2004:

The Dirty Bomb Distraction

http://www.technologyreview.com/energy/13651/

"The biggest danger from radiological weapons is the misplaced panic that they would cause."

"Perhaps they recognized the truth: that the bombs news value could be greater if it were discovered before it went off. For such weapons, the psychological impact can be greater than the limited harm they are likely to cause."

The threat of the dirty bomb is way over-hyped and over-blown.

The good thing about science is that it is true, whether or not you believe in it.
--Neil deGrasse Tyson

PamW

[bananas]

12. Muller is a fucking idiot, a climate denier, and a fucking idiot.

Somebody had to say it.

edit to add for the fucking imbeciles:

"Prominent climate change denier now admits he was wrong (+video)"
"Richard Muller, who directed a Koch-funded climate change project, has undergone a 'total turnaround' on his stance on global warming, which he now admits is caused by human activity."
By Neela Banerjee, Tribune Washington Bureau (MCT) / July 30, 2012
http://www.csmonitor.com/Science/2012/0730/Prominent-climate-change-denier-now-admits-he-was-wrong-video

Holy shit this guy has been fucking wrong all along why the fuck would anyone believe him...

[PamW]

17. Actually...Muller has done climate scientists a favor.

bananas,

Actually Professor Muller pointed out a number of "holes" or deficiencies in the climate science.

Good climate scientists took him seriously; and filled in the missing data.

That's how we make advancements in science; you have somebody that doesn't "follow the herd", but makes an independent assessment, and discovers the "holes" in the theory.

That's NOT called being wrong.

Besides, we aren't discussing climate science here; we are discussing dirty bombs.

Whether someone is correct or not about climate science says NOTHING about whether they are correct about dirty bombs.

In any case, if he were as bad a scientist as you claim; why is he still teaching at the University of California - Berkeley?

The answer is; because he IS a good scientist.

PamW

[quadrature]

23. same crap, different decade

I've heard the same
same 'wind and solar' BS
since the mid seventies.

[PoliticAverse]

26. It's 30 years now for fusion reactors!? They were 10 years away 30 years ago... n/t

[DetlefK]

34. That were blind guesses. Today we have prototypes and educated guesses.

http://en.wikipedia.org/wiki/DEMO

[jeff47]

3. The important detail

Thorium reactors require neutrons to be shot at the thorium. Turn off the neutrons, and the fission slows to the point where the core is cold.

So let's say an earthquake and tidal wave have struck your nuclear plant. If it's a Uranium plant, fission keeps happening. Your cooling systems have failed. Meltdown.

If it's a thorium plant, fission stops when your neutron source turns off. Doesn't matter that the cooling systems failed, because the core is not producing significant heat without that neutron source. No meltdown.

[PamW]

4. Sorry but that's WRONG!

jeff47,

BOTH thorium-fueled and uranium-fueled reactors require neutrons. In fact, thorium is NOT fissile; it doesn't give you energy when hit with a neutron. What happens with thorium is that it transmutes into Uranium-233; and THAT will fission and give you energy when hit by a neutron.

In either case, thorium-fueled or uranium-fueled; if you have an earthquake and drop the control rods which soak up the neutrons; you don't have neutrons in the core in either case.

But that's NOT the problem. The problem is all the fission products that are the remnants of split atoms from all the fissions in the past that gave you energy. THOSE are still radioactive, and that radioactivity produces heat. Initially, the heat is about 7% of the reactor power.

Thus if you have a 1 Gw(electric) power plant, then the reactor is about 3 Gw(thermal) = 3,000 Mw(t)

So initially after the cessation of fission, the thermal heat in the reactor is 210 Mw(t) due to fission product decay energy. That's what gives you the meltdown.

Unfortunately, the thorium-fueled reactor is just as susceptible as is a uranium-fueled reactor.

However, there is a way to mitigate the problem with EITHER; and that is with a liquid fueled reactor like the LFTR.

In a liquid fuel reactor; you are constantly reprocessing the circulating fuel online and taking the fission products out. That means you don't have them sitting in the reactor to add to the heat.

In either case; if you have fission of any type; you have fission products, and if those fission products are left in the core; then you can have a meltdown even after the fission reactions stop due to radioactive decay of fission products.

PamW

[jeff47]

5. Actually, that's entirely the point

In fact, thorium is NOT fissile; it doesn't give you energy when hit with a neutron

And that's entirely they point.

If you have a thorium reactor, you have to have an external neutron source to make it critical. Shut off the neutrons, and no new fission will start. Thus it doesn't matter if the control rods have melted/burned or got stuck outside the reactor or any other such problem. The reactor will stop.

Uranium reactors generate their own neutrons - the fuel is enriched so that U-235 makes the neutrons to trigger fission in U-238. The fuel is critical all on it's own. No control rods, and the reactor is going to be a big problem.

Yes, the decay products can produce heat, but the problem in an old-fashioned uranium reactor is that heat disrupts the control rods, and the reactor goes critical again. The decay products start a meltdown, but the uranium finishes it.

Thorium reactors are much more like the LFTR you are describing - the decay heat in both systems can not cause the reactor to go critical again.

[PamW]

6. Sorry but that's WRONG again

jeff47

NOPE - even a sub-critical source-driven system has problems with decay heat.

Yes, the decay products can produce heat, but the problem in an old-fashioned uranium reactor is that heat disrupts the control rods, and the reactor goes critical again. The decay products start a meltdown, but the uranium finishes it.

The above is 100% WRONG!!

Criticality is NOT a function of heat from decay products. Criticality is a function of materials and geometry. When you drop the control rods in a reactor - it goes sub-critical and STAYS sub-critical.

You don't know where the heat that causes the meltdown comes from. It is NOT fission heat that causes the meltdown; it is decay heat from the fission products. The heat due to the radioactive decay of fission products at equilibrium is 7% of the power of the reactor. When the reactor goes sub-critical, then the fission heating STOPS, but you still have the heat due to the decaying fission products. In my example above, a 1,000 Mw(e) power plant has a 3,000 Mw(thermal) reactor, and 7% of that is 210 Mw(thermal), which is what causes the meltdown.

Don't believe me; here's an explanation courtesy of my alma mater, the Massachusetts Institute of Technology:

Explanation of Nuclear Reactor Decay Heat

http://mitnse.com/2011/03/16/what-is-decay-heat/

When there is a SCRAM, where all the control rods are inserted and the reactor is shutdown, the fission reactions essentially stop and the power drops drastically to about 7% of full power in 1 second. The power does not drop to zero because of the radioactive isotopes that remain from the prior fissioning of the fuel. These radioactive isotopes, also called fission products, continue to produce various types of radiation as they decay, such as gamma rays, beta particles, and alpha particles. The decay radiation then deposits most of its energy in the fuel, and this is what is referred to as decay heat.

It's all right there. When you SCRAM or shutdown the reactor, the fissions STOP; the reactor is NOT critical.

If you produced nuclear energy from PRIOR fissions, then you have fission products.

If you have fission products; you have decay heat.

PamW

[jeff47]

7. Try reading.

Criticality is NOT a function of heat from decay products.

I never said it was.

What I said is decay heat can disrupt the control rods, causing a uranium reactor to go critical again.

When you drop the control rods in a reactor - it goes sub-critical and STAYS sub-critical.

As long as they remain intact.

Too much heat will cause them to melt or catch fire, depending on what they're made of. And when that happens, the reactor goes critical again.

When the reactor goes sub-critical, then the fission heating STOPS, but you still have the heat due to the decaying fission products

Now spend a moment thinking about the reactor after it's been SCRAMed. You've dropped the control rods, so the Uranium isn't critical, but the core's still really damn hot. So you have to keep cooling it.

Now you take out the cooling pumps and dump all the coolant from the core. That causes the core to get hotter since you aren't removing decay heat. Hot enough that the control rods are now in danger - depending on what they're made of, they melt or catch fire (Carbon control rods work, but they were a rather bad idea). In either case, the control rods are no longer where they were supposed to be. They're in a puddle on the bottom of the reactor, or they're now smoke and soot in the reactor building.

Once the control rods have been disrupted, uranium fission starts again and the meltdown gets even worse.

Thorium can't do that. That is the point of using thorium for fuel instead of uranium. Uranium cores become critical again when the control rods are destroyed by the meltdown. Thorium cores can not because they need a neutron source to be critical.

It's all right there. When you SCRAM or shutdown the reactor, the fissions STOP; the reactor is NOT critical.

Time doesn't stop when the reactor is SCRAMed. And control rods are not indestructible.

[PamW]

8. 100% WRONG!! AGAIN!!

Last edited Thu Oct 31, 2013, 04:57 PM - Edit history (1)

jeff47,

100% WRONG in every thing you said.

What I said is decay heat can disrupt the control rods, causing a uranium reactor to go critical again.

WRONG - "disrupting" the control rods doesn't make the reactor go critical again.
WRONG - that the control rods have to stay intact. The absorbing material is STILL THERE regardless of what state it's in. The absorbing capacity of the control rods DO NOT go away; even if you melt them. This is nuclear physics 101.

WRONG again that the control rods are going to catch fire. They are made of metals like cadmium.

I agree that you need to cool the core. But you said you needed to cool the core because it went critical again. That is 100% WRONG.

The core goes sub-critical when the control rods are dropped because of the addition of absorbing material, and it DOESN'T MATTER if that material melts; the nuclear properties of being a neutron absorber are INDEPENDENT of the physical properties and whether the material is solid or liquid.

Once the control rods have been disrupted, uranium fission starts again and the meltdown gets even worse.

100% WRONG "Disruption" of control rods does NOT make the uranium fission again.

Thorium cores can not because they need a neutron source to be critical.

WRONG a neutron source can't make a sub-critical system critical. You can drive a sub-critical system with a source and produce some heat; but it is WRONG to say that such a system is "critical".

Again nuclear physics 101; "criticality" is a property of the materials and their geometry; and NOT the neutrons.

You can have a critical system with no neutrons. Think of criticality as the gain of an audio amplifier. You can have the gain cranked to "11", and the amplifier is acting like an amplifier even if you have no signal.

What you are saying above is that you can have an electronic circuit that has below unity gain i.e. is not an amplifier, and if you put a signal in; then it has gain above unity, i.e. is an amplifier. That's what saying neutrons make the sub-critical system critical is saying.

Finally; again - the nuclear absorption properties of the control rods is NOT AFFECTED by being melted or destroyed. The state of being melted or destroyed, or disrupted, is a property of a whole bunch of atoms. If they are solid, they are arranged in a crystal, if they are melted, they are amorphous.

However, when a neutron interacts with the nucleus of a cadmium atom; it has NO IDEA of whether that atom is in a crystal lattice ( solid ) or not ( melted ). All it knows is that it is interacting with nucleus the nuclear strong force of which is producing a potential well that the neutron is falling into.

The neutron has absolutely NO IDEA about structures that are orders of magnitude greater in scale.

You are JUST PLAIN 100% WRONG.

BTW - you are talking with someone who used to DESIGN reactors. I was part of Dr. Till's team at Argonne that designed the IFR.

http://www.pbs.org/wgbh/pages/frontline/shows/reaction/interviews/till.html

PamW

[jeff47]

10. Because solid matter and liquid matter behave the same?

WRONG - "disrupting" the control rods doesn't make the reactor go critical again.
WRONG - that the control rods have to stay intact. The absorbing material is STILL THERE regardless of what state it's in.

Well, you could go back to your previous post, where you talked about how the placement of the control rods were critical.

And then you could ponder what would happen when the solid control rods became liquid.

Hint: They wouldn't be in such a carefully selected position anymore. They're in a puddle at the bottom of the reactor.

WRONG again that the control rods are going to catch fire. They are made of metals like cadmium.

Reading. You need to try it. Because I never said all control rods were flammable.

Control rods have been made of various materials. In US reactors, they're currently a metal alloy. This wasn't always the case. Carbon works nicely as a control rod. The downside is it's flammable. Which has lead to some exciting events in the development of nuclear power.

The core goes sub-critical when the control rods are dropped because of the addition of absorbing material, and it DOESN'T MATTER if that material melts; the nuclear properties of being a neutron absorber are INDEPENDENT of the physical properties and whether the material is solid or liquid.

But it does matter where that material is located. When it's in a puddle at the bottom of the reactor, it can't absorb any neutrons at the top of the reactor. Because it is no longer there.

WRONG a neutron source can't make a sub-critical system critical. You can drive a sub-critical system with a source and produce some heat; but it is WRONG to say that such a system is "critical".

You can't seem to understand that liquids flow. You think I'm going to worry about being completely and utterly accurate with terminology when you can't understand that liquids flow?

Again nuclear physics 101; "criticality" is a property of the materials and their geometry; and NOT the neutrons.

Again, no. If the neutrons were irrelevant, geometry wouldn't matter. The geometry matters because that controls neutron flux through the material. And it's the neutrons smacking into U-238 or Thorium that trigger fission in those materials in a nuclear reactor.

Finally; again - the nuclear absorption properties of the control rods is NOT AFFECTED by being melted or destroyed. The state of being melted or destroyed, or disrupted, is a property of a whole bunch of atoms. If they are solid, they are arranged in a crystal, if they are melted, they are amorphous.

They are amorphous, and arranged in a puddle at the bottom of the reactor.

BTW - you are talking with someone who used to DESIGN reactors. I was part of Dr. Till's team at Argonne that designed the IFR.

The fact that you don't understand liquids can flow makes this claim pretty obvious bullshit.
The fact that you are unfamiliar with the many early experiments using carbon control rods confirms that.

[PamW]

16. Do you always argue with experts when you aren't one?

Last edited Sat Nov 2, 2013, 07:30 PM - Edit history (2)

jeff47,

Let me take you points one by one:

Hint: They wouldn't be in such a carefully selected position anymore. They're in a puddle at the bottom of the reactor.

Before the SCRAM the control rods are OUT of the reactor core. True that a solid rod in the middle of the reactor has more "worth", as it is called; than one at the bottom of the reactor. However, because the reactor started at exactly critical, the addition of ANY absorber to the reactor core will drive it sub-critical, and it will STAY sub-critical.

Control rods are made out of a "neutron poison"; and that inspires an analogy. Suppose you were to swallow a bunch of mouse / rat pellets; the strychnine-laced pellets that are used to poison / kill the mice / rats that may be infesting your home. Someone points out that the acid in your stomach is going to "disrupt" (YOUR WORD) the pellet, and that the pellet isn't going to stay intact, but is going to dissolve and the strychnine is going to sit at the bottom of your stomach. So are you "out of the woods" with regard to being poisoned? NOPE!!!

Well that's the feeble argument that you are attempting to foist onto the readership here. The pellets don't have to maintain their integrity in order to work. The fact that the pellets are going to dissolve isn't going to help you. You've swallowed a poison and your are in trouble. That poison works on the molecular level and doesn't care whether or not the pellet is "disrupted" or not.

The control poison in the reactor works similarly. In fact, the control poison in the reactor is going to be even MORE effective if the control rod melts due to a phenomenon known as "self-shielding". What "self-shielding" is about is the fact that the control poison in the very center of the control rod is going to see very few neutrons because any neutrons that it would see would have to traverse through the outer portion of the rod, and would be absorbed by the control poison in the outer portion of the rod. When the rod melts; that inner material essentially "gets out from behind" the outer material, and that inner material can have a greater effect.

Carbon works nicely as a control rod.

100% WRONG Carbon is a moderator, the addition of carbon softens the neutron spectrum, and INCREASES reactivity whereas the purpose of the control rod is to DECREASE reactivity. Saying that carbon works as a control rod is like saying that since water is a liquid, and water puts out fires, then all liquids are good at putting out fires, so gasoline would be good at putting out a fire.

When it's in a puddle at the bottom of the reactor, it can't absorb any neutrons at the top of the reactor. Because it is no longer there.

That's true but it is IMMATERIAL. Criticality is a property of the ENTIRE core, and neutrons can travel through out the core. The control rod sitting at the bottom of the core doesn't absorb neutrons that are near the top of the core, but it does absorb neutrons that are at the bottom.

In fact, Boiling Water Reactors (BWRs) have control rods that enter from the BOTTOM. Look at the following schematic of a BWR reactor:



The bottom most notation on the left side is about the control rod drive mechanism and the arrow points to the BOTTOM of the reactor vessel. So just because control rods are at the bottom doesn't mean that they are ineffective. There's nothing "magic" about control rods entering at the top so they have to stay at the top.

Let's take an analogy. We have a stool with 3 legs, numbered 1, 2, and 3. I cut off leg 3. You tell me that leg 1 is still intact so I haven't compromised the stability of the stool. The leg 1 is still intact. DOESN'T MATTER. I cut off leg 3. The stool needs that leg too. That's where you don't understand "criticality", because it is a property not of individual regions, it a property of the entire core. If I start with a critical reactor, and I add absorber to ANYWHERE in the core; I'm driving the reactor sub-critical. It would be more sub-critical if I add absorber to the core center; but adding absorber ANYWERE in the core will drive it sub-critical to a degree.

Again, no. If the neutrons were irrelevant, geometry wouldn't matter. The geometry matters because that controls neutron flux through the material.

100% WRONG Criticality depends on BOTH materials and geometry, and doesn't depend on whether neutrons are present or not.

The equation you solve for determining whether the reactor is critical or not is the Boltzmann Transport Equation. It is an integro-differential equation in the neutron flux.

http://en.wikipedia.org/wiki/Neutron_transport

We can abstract the Boltzmann equation as follows:

(A)(flux) = (1/k)(F)(flux)

The operator A gives the absorption / leakage / destruction of neutrons. The operator F gives you the fissions. Both these operators operate on the flux.

The system may or may not be critical; that is absorption may exceed production, or absorption could equal production in which case the equation would balance, or absorption may be less than production. In any case, we can mathematically force the system to be balance by adjusting the quantity "k" which is the eigenvalue of the system. If there isn't enough production, set k to a number less than 1, so 1/k is greater than 1 and that artificially boosts production. If absorption is less than production, set k to a number greater than 1 so 1/k is less than 1, and we can artificially balance the equation again.

Note that the above equation is homogeneous, that is, if we put all the terms in the dependent variable "flux" on the left, the right hand side is zero.

( A - (1/k) F )(flux) = 0

This is like having an equation:

c x = 0

For c not equal to 0; there is only one solution, the trivial one x = 0.

However, if c = 0; then the equation is singular and we have lots of solutions

That is what DEFINES criticality. In order for the above equation in the flux to have a non-trivial solution, then the operator ( A - (1/k) F ) has to be singular. That will happen only for certain values of k; that is only for certain eigenvalues, k. If the fundamental eigenvalue is 1; then the system is crititcal.

It doesn't matter whether there are neutrons or not in the system; it can be critical without neutrons.

That is why reactors are ALWAYS started up with neutron sources in them. The instrumentation measures neutrons. If there are no neutrons for the instrumentation to detect; one could drive the reactor critical, and then super-critical without even knowing it if there are no neutrons. That's why you always start up the reactor with a source.

Again, the audio amplifier makes a nice analogy. If you have no signal going into your amplifier; you can crank the volume control above the level that would blow your speakers out. You don't know that you have it cranked too high; because there's no signal.

We could use your logic about geometry and neutrons. You claim that the only reason geometry matters is due to the effect on the neutrons. Well, the volume control on the amplifier affects the signal. However, I can still crank the volume control to a high gain that will blow the speakers whether or not I have a signal. The amplifier is still an amplifier in the electrical engineering sense; even if there is no signal.

Likewise, a reactor can be critical or super-critical even if you don't have neutrons.

And it's the neutrons smacking into U-238 or Thorium that trigger fission in those materials in a nuclear reactor.

99.8% WRONG AGAIN. Uranium-238 is NOT "fissile"; it is "fissionable". The difference is that "fissile" connotes a nuclide that will fission with neutrons of any energy, while "fissionable" means that there is a threshold reaction. U-238 will ONLY fission with neutrons above 1 MeV or so; and there are VERY, VERY FEW neutrons of that energy. Hence the 99.8% WRONG.

Again the fact that you keep harping on that the control rod material is at the bottom of the reactor is IMMATERIAL

The fact that you don't understand liquids can flow makes this claim pretty obvious bullshit.

You haven't proven that I don't understand that liquids don't flow. Of course, I understand that liquids flow.
It is YOU that is missing the point, that it DOESN'T MATTER. The neutrons are travelling ALL over the core and will be absorbed by the control material even if it is sitting at the bottom of the core.

Consider the following. We make a box out of mirrors that are facing inwards. So I have this box, with a room inside, the walls of which are all mirrors. Now suppose I put a black object in one of the corners. Now we shine some light into the box and seal it up. The corner of the room is not the best place to put the black object if we want to absorb light; but that light is going to get absorbed by the object nonetheless. It will ricochet around the room until it finds that black object, at which point it will be absorbed. Same thing for neutrons. They will either leak out or find that control material on the bottom of the reactor.

You start with a critical reactor and you add absorber; you have a sub-critical reactor NO MATTER WHERE you add absorber.

Carbon accentuates the nuclear fission reactions; not depresses fission reactions. You evidently MISUNDERSTOOD the early experiments because they didn't use carbon control rods. Fermi's first reactor CP-1 used cadmium, indium, and silver, NOT carbon.

http://en.wikipedia.org/wiki/Chicago_Pile-1

Made of a large amount of graphite and uranium, with "control rods" of cadmium, indium, and silver, ...

Carbon was the moderator, but "moderator" means it moderates the neutron energy; which INCREASES criticality. That's probably the source of your MISUNDERSTANDING.

PamW

[GliderGuider]

9. As long as they target deployment for after 2040 I'm fine with it.

Why after 2040 you ask?

Because by 2040 civilization will probably have broken down due to accumulating multi-factorial stresses, and that will have rendered the whole ridiculous issue moot.

Plus, by then I should be safely dead, with no whelp left behind.

[kristopher]

18. Thorium Fuel – No Panacea for Nuclear Power

Thorium Fuel – No Panacea for Nuclear Power
Thorium “fuel” has been proposed as an alternative to uranium fuel in nuclear reactors. There are not “thorium reactors,” but rather proposals to use thorium as a “fuel” in different types of reactors, including existing light-water reactors and various fast breeder reactor designs.

Thorium, which refers to thorium-232, is a radioactive metal that is about three times more abundant than uranium in the natural environment. Large known deposits are in Australia, India, and Norway. Some of the largest reserves are found in Idaho in the U.S. The primary U.S. company advocating for thorium fuel is “Thorium Power”. [1] Contrary to the claims made or implied by thorium proponents, however, thorium doesn’t solve the proliferation, waste, safety, or cost problems of nuclear power, and it still faces major technical hurdles for commercialization.

You can download the thorium factsheet here
http://ieer.org/wp/wp-content/uploads/2012/04/thorium2009factsheet.pdf


From the factsheet

<snip>
Not a Proliferation Solution
...It has been claimed that thorium fuel cycles with reprocessing would be much less of a proliferation risk because the thorium can be mixed with uranium-238. In this case, fissile uranium-233 is also mixed with non-fissile uranium-238. The claim is that if the uranium- 238 content is high enough, the mixture cannot be used to make bombs without a complex uranium enrichment plant. This is misleading. More uranium-238 does dilute the uranium-233, but it also results in the production of more plutonium-239 as the reactor operates. So the proliferation problem remains – either bomb-usable uranium-233 or bomb-useable plutonium is created and can be separated out by reprocessing.

Further, while an enrichment plant is needed to separate U-233 from U-238, it would take less separative work to do so than enriching natural uranium. This is because U-233 is five atomic weight units lighter than U-238, compared to only three for U-235. It is true that such enrichment would not be a straightforward matter because the U-233 is contaminated with U-232, which is highly radioactive and has very radioactive radionuclides in its decay chain. The radiation-dose-related problems associated with separating U-233 from U-238 and then handling the U-233 would be considerable and more complex than enriching natural uranium for the purpose of bomb making. But in principle, the separation can be done, especially if worker safety is not a primary concern; the resulting U-233 can be used to make bombs. There is just no way to avoid proliferation problems associated with thorium fuel cycles that involve reprocessing. Thorium fuel cycles without reprocessing would offer the same temptation to reprocess as today’s once-through uranium fuel cycles....

Not a waste solution

<snip>

About the author:
Arjun Makhijani
Arjun Makhijani, President of IEER, holds a Ph.D. in engineering (specialization: nuclear fusion) from the University of California at Berkeley. He has produced many studies and articles on nuclear fuel cycle related issues, including weapons production, testing, and nuclear waste, over the past twenty years. He is the principal author of the first study ever done (completed in 1971) on energy conservation potential in the U.S. economy. Most recently, Dr, Makhijani has authored Carbon-Free and Nuclear-Free: A Roadmap for U.S. Energy Policy (IEER Press), the first analysis of a transition to a U.S. economy based completely on renewable energy, without any use of fossil fuels or nuclear power. He is the principal editor of Nuclear Wastelands and the principal author of Mending the Ozone Hole, both published by MIT Press.

[PamW]

19. The Rest of the Story - the part that Arjun and kristopher don't tell you...

As Paul Harvey used to say, "Here's the Rest of the Story."

Arjun and kristopher left out the part about why the thorium fuel cycle is proliferation resistant.

The reason was covered by MIT Professor Mujid Kazimi in his article Thorium Fuel for Nuclear Energy, to be found in the September-October 2003 issue of the scientific journal The American Scientist:

http://www.americanscientist.org/issues/num2/thorium-fuel-for-nuclear-energy/1

On the 3rd page of the article, Professor Kazimi discusses why the thorium fuel cycle is proliferation resistant:

http://www.americanscientist.org/issues/pub/thorium-fuel-for-nuclear-energy/3

Even if a terrorist group wanted to use the blanket plutonium for making a terrifying (if not terribly powerful) bomb, extracting it from Radkowsky's thorium fuel—indeed from any thorium fuel used in a reactor—would be more difficult than removing it from today's spent fuel. The spent blanket fuel contains uranium-232, which in the course of a few months decays into isotopes that emit high-energy gamma rays. Thus pulling out the plutonium would require significantly beefed-up radiation shielding and a more widespread use of remotely operated equipment within the reprocessing facility, further complicating an already challenging task. And the abundance of uranium-232 and its highly radioactive products in the spent fuel would probably thwart any effort to separate uranium-233 (which, being fissionable, could also be used for a bomb) from uranium-238.

Of course, Arjun Makhijani and kristopher conveniently leave out the Uranium-232 issue which makes proliferation problematical.

The good thing about science is that it is true, whether or not you believe in it.
--Neil deGrasse Tyson

PamW

[kristopher]

20. Really? From the snip above

..It has been claimed that thorium fuel cycles with reprocessing would be much less of a proliferation risk because the thorium can be mixed with uranium-238. In this case, fissile uranium-233 is also mixed with non-fissile uranium-238. The claim is that if the uranium- 238 content is high enough, the mixture cannot be used to make bombs without a complex uranium enrichment plant. This is misleading. More uranium-238 does dilute the uranium-233, but it also results in the production of more plutonium-239 as the reactor operates. So the proliferation problem remains – either bomb-usable uranium-233 or bomb-useable plutonium is created and can be separated out by reprocessing.

Further, while an enrichment plant is needed to separate U-233 from U-238, it would take less separative work to do so than enriching natural uranium. This is because U-233 is five atomic weight units lighter than U-238, compared to only three for U-235....

Makhijani continues:
... It is true that such enrichment would not be a straightforward matter because the U-233 is contaminated with U-232, which is highly radioactive and has very radioactive radionuclides in its decay chain.

He further states:
The radiation-dose-related problems associated with separating U-233 from U-238 and then handling the U-233 would be considerable and more complex than enriching natural uranium for the purpose of bomb making.But in principle, the separation can be done, especially if worker safety is not a primary concern; the resulting U-233 can be used to make bombs. There is just no way to avoid proliferation problems associated with thorium fuel cycles that involve reprocessing.

He also notes that, "(t)horium fuel cycles without reprocessing would offer the same temptation to reprocess as today’s once-through uranium fuel cycles....".

The profile of the proliferation risk isn't particularly mitigated and it definitely isn't eliminated; it is only somewhat altered.

Full fact sheet in PDF here
http://ieer.org/wp/wp-content/uploads/2012/04/thorium2009factsheet.pdf
http://ieer.org/wp/wp-content/uploads/2012/04/thorium2009factsheet.pdf

[PamW]

21. Arjun is WRONG!!

The profile of the proliferation risk isn't particularly mitigated and it definitely isn't eliminated; it is only somewhat altered.

kristopher,

Arjun is WRONG. Arjun mentions the Uranium-232 issue, but minimizes it as not a big problem.

Arjun is NOT a nuclear weapons physicist.

The Uranium-232 is a HUGE problem that Arjun minimizes, but MIT Professor Kazimi gets it RIGHT.

You have to learn to quit basing your opinions on what activists like Arjun states.

Why not base your opinions on what unbiased scientists like an MIT Professor states?

Besides, I find proliferation arguments non-compelling. Why should the USA forego a technology just because that technology could be used for nuclear weapons. The USA isn't going to use the technology to proliferate. The USA already has nuclear weapons. I can see restricting the technology from non-nuclear weapons states, like we do with enrichment technology and reprocessing technology. However, the USA isn't a potential proliferator.

The good thing about science is that it is true, whether or not you believe in it.
--Neil deGrasse Tyson

PamW

[kristopher]

22. "Why not base your opinions on what unbiased scientists like an MIT Professor states?"

Dr. Mahkijani is highly qualified and history has shown his analysis to be more accurate than anything coming out of MIT's nuclear engineering department. For example, he led the way in debunking the cost quoted by NRG for the reactors they filed to build at San Antonio's South Texas site. This was after years of MIT rubber-stamping the nuclear industry's lowball cost estimates for new plants.

Assessing Nuclear Plant Capital Costs for the Two Proposed NRG Reactors at the South Texas Project Site

Central conclusion and recommendation
The overall finding of this report is that NRG’s range of $6 billion to $7 billion is obsolete. The best available estimates indicate that capital costs would likely be about a factor of two or more higher, even without taking into account the potential for real cost escalations during construction, delays, and other risks. The risks to CPS, as a municipal utility and to its ratepayers as well as to the taxpayers of San Antonio are great. Due diligence demands that CPS participation in the project should not be pursued until an independent, detailed study with current cost estimates of the plants and alternatives to it are complete and have been publicly disclosed and discussed.

Full report here: http://nukefreetexas.org/downloads/makhijani_cost_report.pdf

MIT's questionable behavior has even attracted the attention of ethicists. As stated in the Journal of Science and Engineering Ethics:

Likewise, perhaps because official US national policy and the relevant federal
agencies are pro-nuclear, even US-government agencies trim cost data on nuclear plants, as the Tennessee Valley Authority did recently. It used “overnight costs only” to quote prices for its reactors.

Following most analysts, the authors of the 2009 MIT study also quote (pp. 5–6) total nuclear-plant costs as “overnight costs” and say that “this total [nuclear-power-plant] cost, which is exclusive of financing cost, is $4,706/kW”; noting that the earlier (2003) MIT analyses also compared overnight costs, “as described in the MIT (2003) Future of Nuclear Power study,” the 2009 MIT authors attempt to justify their interest-cost-trimming procedures by saying that using overnight costs “represents the standard basis for quoting comparable costs across different plants”. Likewise, when the 2009 MIT authors assume a reactor-construction-time period, they again follow the 2003 MIT authors and say (p. 4) nuclear-plant “construction is planned to occur over a 5-year period”.

However, most experienced nuclear operators, like Florida Power and Light, say US new-nuclear-plant-construction time is 12 years, not the 5 years assumed by the MIT authors. Likewise, the US National Academy of Sciences estimates at least 11 years. The average UK-nuclear-plant-construction time is 11 years; in France, 14 years; in Japan, 17 years; in Eastern Europe, 15 years. Nuclear proponents admit that building the latest US reactors took 23 years.

Trimming nuclear-interest rates to 0 also is misleading. Given plant delays, construction-cost overruns, equipment malfunctions, poor credit ratings, plant cancellations, and energy-market competition, most private investors/banks refuse all nuclear loans. Those few, that will loan, require 15% minimum-nuclear-interest rates.

Facing 15% rates, instead industry has successfully lobbied government, so that taxpayers subsidize nuclear-interest rates when markets will not. Proponents admit that in every nation, nuclear power is the most-subsidized energy technology. Industrial-consulting firms showed that during 1947–1999, atomic energy received 96% of $150 billion total US subsidies for nuclear, wind, and solar, and this trend continues.

Rather than 15% nuclear-interest rates, the WNA admits “most studies,” e.g., including those from MIT, assume overnight costs, that is, 0 nuclear-interest costs, 0 nuclear-interest rates, and 0 nuclear-construction times...

Climate Change, Nuclear Economics, and Conflicts of Interest
Kristin Shrader-Frechette
Department of Philosophy and Department of Biological Sciences, University of Notre Dame, 100
Sci Eng Ethics
DOI 10.1007/s11948-009-9181-y

[PamW]

25. Economic forecasts doesn't convey SCIENTIFIC credibility

kristopher,

HA HA HA Do you REALLY believe that the ability to make economic forecasts as something that confers SCIENTIFIC credibility? Economics is almost stochastic; costs rise or fall unconstrained by deterministic laws.

If the ability to predict events controlled by probability was indicative of scientific correctness; then the person that can win at the Roulette table should be considered a scientific expert.

The MIT Nuclear Engineering Department does at times make economic forecasts; but their real forte is NOT in economic forecasting; but in nuclear science where their reputation is unassailed.

Evidently you don't understand that whether one can make a nuclear weapon out of material that contains an intense gamma source is NOT an economic question; but one that has to do with PHYSICS and not economics.

I am MONUMENTALLY UNIMPRESSED by the "economic" argument above.

Let's get down to PHYSICS which is what counts here.

The question is whether an intense gamma radiation emitter can be used within a nuclear weapon as the core.

Unlike alpha particles ( from Plutonium ) that can be shielded with a piece of paper, or beta particles ( electrons ) that can be shielded with a thin metal shield; gamma radiation is much more penetrating. A gamma source is analogous to an intense flame.

Now, think about it. What would you NOT want to be holding if you were in the close proximity to an intense flame and its radiation? How about a chunk of chemical high explosive? You'd be taking your life in your hands; because the radiant energy deposition in the high explosive could detonate the high explosive.

So you don't want to have high explosive anywhere in the vicinity of an intense radiant energy source!!

So how do you make a nuclear weapon? You wrap the nuclear material with high explosive which compresses the nuclear material to super-criticality when the explosive is detonated. However, you do NOT want that nuclear core to be something that is going to detonate the high explosive that you were going to use to implode the nuclear material. You only want your high explosives to detonate by action of the detonators in response to your command. You don't want your high explosive detonating spontaneously due to radiant energy deposition.

What about shielding the radiation. One could do that with a large quantity of lead. However, with all that lead in the way; how is the high explosive going to implode your nuclear material? You can't have your nuclear material wrapped in high explosive, and you can't shield the high explosive from the nuclear material and still have it function as a nuclear bomb.

THAT is why you can't make nuclear weapons out of an intense radiation source

I'm LAUGHING at the SILLY argument that since someone made a correct economic forecast; that somehow confers on that person the credibility to decide what can or can not be made into a nuclear weapon.

Arjun may have made a correct cost prediction; but as a nuclear weapons physicist; he's an IDIOT. Arjun has demonstrated time and time again that he can't hack the science.

It seems to be a fad. Over and over again, one sees people who trained in the nuclear sciences field, a field that has some of the leading scientific intellects of the day; and they "wash out". They can't cut it in the field with so many truly high intellects. So they quit the field, and in their bitterness, they turn to being critics. They can't hack it; so they criticize the field. Some how the anti-nukes look upon these scientific "wash outs" as heroes to be taken seriously.

One wonders.

The good thing about science is that it is true, whether or not you believe in it.
--Neil deGrasse Tyson

PamW

[kristopher]

30. Well, how about being elected an APS Fellow?

Far from being a "scientific washout" Dr. Mahkijani is clearly an exceptional physicist. Being an APS Fellow conveys more credibility than hysterical anonymous error-riddled ranting on the internet, don't you agree?


What is the American Physical Society?

American Physical Society
From Wikipedia, the free encyclopedia
American Physical Society
http://www.aps.org/
The American Physical Society is the world's second largest organization of physicists, behind the Deutsche Physikalische Gesellschaft. The Society publishes more than a dozen scientific journals, including the prestigious Physical Review and Physical Review Letters, and organizes more than 20 science meetings each year. It is also a member society of the American Institute of Physics.[1]

The American Fellows

Any active APS member is eligible for nomination and election to Fellowship. The criterion for election is exceptional contributions to the physics enterprise; e.g., outstanding physics research, important applications of physics, leadership in or service to physics, or significant contributions to physics education. Fellowship is a distinct honor signifying recognition by one's professional peers.
Each nomination is evaluated by the Fellowship committee of the appropriate APS division, topical group or forum, or by the APS General Fellowship committee. After review by the full APS Fellowship Committee, the successful candidates are elected by APS Council.
http://www.aps.org/programs/honors/fellowships/

Makhijani, Arjun [2007]
Institute for Energy & Environmental Research
Citation: For his tireless efforts to provide the public with accurate and understandable information on energy and environmental issues.
Nominated by: Forum on Physics and Society
http://www.aps.org/programs/honors/fellowships/archive-all.cfm?initial=M&year=&unit_id=&institution=

And I note that the "G" tab for Fellows jumps directly from Greenfield, Charles to Greenwald, Martin J. with no Dr.GregX anywhere to be found.

A recognized authority on energy issues, Dr. Makhijani is the author and co-author of numerous reports and books on energy and environment related issues, including two published by MIT Press. He was the principal author of the first study of the energy efficiency potential of the US economy published in 1971. He is the author of Carbon-Free and Nuclear-Free: A Roadmap for U.S. Energy Policy (2007).

In 2007, he was elected Fellow of the American Physical Society. He was named a Ploughshares Hero, by the Ploughshares Fund (2006); was awarded the Jane Bagley Lehman Award of the Tides Foundation in 2008 and the Josephine Butler Nuclear Free Future Award in 2001; and in 1989 he received The John Bartlow Martin Award for Public Interest Magazine Journalism of the Medill School of Journalism, Northwestern University, with Robert Alvarez. He has many published articles in journals and magazines as varied as The Bulletin of the Atomic Scientists, Environment, The Physics of Fluids, The Journal of the American Medical Association, and The Progressive, as well as in newspapers, including the Washington Post.

Dr. Makhijani has testified before Congress, and has appeared on ABC World News Tonight, the CBS Evening News, CBS 60 Minutes, NPR, CNN, and BBC, among others. He has served as a consultant on energy issues to utilities, including the Tennessee Valley Authority, the Edison Electric Institute, the Lawrence Berkeley Laboratory, and several agencies of the United Nations.

Education:
Ph.D. University of California, Berkeley, 1972, from the Department of Electrical Engineering. Area of specialization: plasma physics as applied to controlled nuclear fusion. Dissertation topic: multiple mirror confinement of plasmas. Minor fields of doctoral study: statistics and physics.
M.S. (Electrical Engineering) Washington State University, Pullman, Washington, 1967. Thesis topic: electromagnetic wave propagation in the ionosphere.
Bachelor of Engineering (Electrical), University of Bombay, Bombay, India, 1965.
http://ieer.org/wp/wp-content/uploads/2011/11/cvarjun.pdf

[PamW]

31. He only washed out in NUCLEAR

kristopher,

Evidently you don't understand that science is a very large field, and someone can be well regarded in one area and NOT another.

I know what the American Physical Society is; it is the professional society for physicists, just as the American Medical Association (AMA) is the professional society for medical doctors. BTW, you have ABSOLUTELY NO IDEA what my last name is; so you are in the WRONG part of the alphabet.

A medical doctor can be an internist and a member of the AMA, but not be a great heart surgeon. If the question is whether a given patient is a good candidate for heart replacement surgery, it's NOT ENOUGH just to be a member in good standing of the AMA. One needs to be one of the very few heart surgeons if one has to have credibility.

However, the real issue here isn't the credentials of Arjun Makhijani. The REAL question is whether one can make a nuclear weapon out of something that is intensely gamma radioactive.

I pointed out the problem that one has in my previous post. I think ANYONE can understand that one doesn't want to have the chemical high explosive that is used to trigger a nuclear weapon anywhere NEAR a high intensity source of radiant energy.

I would hope that YOU see the problem of having chemical high explosive in the vicinity of an intense source of radiant energy. I would have thought Dr. Makhijani would have thought about that too; but evidently it didn't occur to him.

No matter. The problem is pretty OBVIOUS once it is pointed out. What do you think Dr. Makhijani would say if he were a part of this discussion, and the issue of having chemical high explosive in the vicinity of an intense radiant energy source was on the table. I'd think he'd agree.

You have to quit BLINDLY following people just because they have one expertise doesn't mean that they are experts in all fields.

This may be an anonymous forum; but when you see scientific truth on any forum, anonymous or not; one should be able to recognize scientific truth wherever it arises.

The good thing about science is that it is true, whether or not you believe in it.
--Neil deGrasse Tyson

PamW

[kristopher]

32. You are just digging yourself a deeper hole.

You have no credibility at all DrGreg/PamW.

The fact that you seem to think you do would be astounding if we didn't see the same kind of clownish denial of reality as a staple of nearly all of your posts.

[PamW]

35. It APPEARS that way to people who don't know the science

kristopher,

As a non-scientist; you are NOT AT ALL familiar with the tenets of science and the ways of science.

First, we don't BLINDLY put our faith in someone who is a fellow of the American Physical Society, just because they are an APS Fellow. The APS isn't the ONLY professional society for physicists; the other one is the American Institute of Physics:

http://www.aip.org/

The APS has its fellows and publishes "The Physical Review" while the AIP has its fellows and publishes "Physics Today".

Although the APS and the AIP are societies for physicists; NUCLEAR physicists and engineers have their OWN professional society, the American Nuclear Society:

http://www.ans.org/?gclid=CN7rtuuqyboCFRFxQgod9TIALQ

So if you want to find people who are the TOP SCIENTISTS in the NUCLEAR field; you would go look to the American Nuclear Society.

However, the REAL question here revolves around what is / is not possible in the design of nuclear weapons.

Whereas the APS, the AIP, and even the ANS choose their fellows from review of papers, and articles that a scientist publishes; nuclear weapons scientists DO NOT publish in the open literature, as you well can imagine why.

A nuclear weapons scientist can't publish a paper in the open literature that says, "Hey everybody; look at the clever thing I did to make nuclear weapons more efficient, or safer, or more reliable". A nuclear weapons scientist doesn't publish papers like that; so you are NOT going to find the most expert nuclear weapons scientists as Fellows of any scientific professional society.

The DOE has their own SECRET awards for weapons scientists, just as the NSA has their cadre of SECRET award-winning mathematicians that are making / breaking codes. The public isn't going to know who the real experts are in the classified realm of science.

Since we can't count on fellowship in a professional society as any type of standard; we have to look at the PHYSICS which is more reliable anyway than going on who is a fellow of what society. Even society fellows can MAKE MISTAKES in fields that they are not familiar with.

So we have the issue at hand which is whether one can make a nuclear weapon using a material at the weapon core that is an intense radiant energy source. Remember, what encircles the nuclear material in a nuclear weapons - chemical high explosive. You can't put chemical high explosive anywhere you want without concern of how it is going to react to its environment.

Have you ever seen pictures or videos from the inside of a steel foundry? You have workers working with either molten or near molten ingots of steel that are glowing red hot. Look at the pictures of the workers; they are wearing those "aluminum foil" suits. They need the silvery aluminum coating to reflect radiant energy; otherwise they are going to be burned by that radiant energy. Would you approach one of those red-glowing ingots with a brick of C-4 or other high explosive? I wouldn't advise it. While the glowing ingot would burn your skin and flesh, the radiant energy is going to detonate your high explosive. So you can't wrap high explosive around something that is intensely radiating energy.

While a sheet of silvery aluminum reflects radiant heat well; that is NOT true for gamma radiation. It takes a significant thickness of a dense heavy metal like Lead, or many feet of concrete to shield gamma radiation.

In his interview with Frontline, what characteristics did nuclear physicist Dr. Charles Till relate as being the characteristics that made a material impossible to be used for nuclear weapons. Recall:

http://www.pbs.org/wgbh/pages/frontline/shows/reaction/interviews/till.html

Q: So it would be very difficult to handle for weapons, would it?

A: It's impossible to handle for weapons, as it stands.

It's highly radioactive. It's highly heat producing. It has all of the characteristics that make it extremely, well, make it impossible for someone to make a weapon.

Dr Till confirms that the traits of being "highly radioactive" and "highly heat producing" are precisely NOT what you want in a fuel for a nuclear weapon, and that those characteristics make it IMPOSSIBLE to make a weapons with materials with those characteristics.

So anyone that has even the faintest modicum of scientific knowledge can appreciate that intensely radiative materials can NOT be used in weapons. ( I wonder how Arjun missed this fact. )

Additionally, I don't believe that even if there were a proliferation risk, that should dissuade the USA from employing the technology. The USA is ALREADY a nuclear weapons state. The US Government doesn't need to co-op the commercial nuclear industry in order to get material. The US Government built its own facilities at Hanford in Washington, and Savannah River in South Carolina, and other sites to get the nuclear materials needed for weapons. The US Government since back in the Reagan Administration shutdown those facilities, because the USA has all the weapons material it needs. ( Save for making tritium, because that decays and has to be replenished. )

So I don't see you argument as holding ANY CREDIBILITY at all.

Please don't give me any more of those, "You're just digging yourself in deeper" platitudes.

It just means to me and the others here; that you have NO RESPONSE to addressing the issues.

The good thing about science is that it is true, whether or not you believe in it.
--Neil deGrasse Tyson

PamW

[kristopher]

36. More rubbish.

Thanks for proving the point that you are, quite literally, incapable of honest discussion at even the most prosaic level.
The is absolutely no foundation for your position other than a desperate need for self validation. Unfortunately for you, you've been busted for the umpteenth time..

[PamW]

37. What are your CREDENTIALS again???

kristopher,

I note that kristopher offers NO rebuttal to my points; he just denounces them. If what I was saying was truly rubbish; one would think that a rebuttal would be easy. However, kristopher dares not do that; because he's NOT a scientist, he doesn't know when what he says is wrong; and the very next post I will demonstrate his claims to be false with references to University websites, and other authoritative scientific references. I've done that countless times before.

What are YOUR CREDENTIALS again? What expertise do you have to make such a judgment that what I am saying is purely rubbish?

What university did you get your degree(s) in the scientific disciplines from?

Speak up, speak up.. I can't hear you!

I thought so.

The good thing about science is that it is true, whether or not you believe in it.
--Neil deGrasse Tyson

PamW

[kristopher]

38. Your remarks don't require a "rebuttal"

They are self-evident rubbish that you've concocted as you flop from one untenable position to the next.

Dr. Makhijani is qualified and well respected.

You are an anonymous anti-environmentalist internet presence that will say absolutely anything, no matter how untethered from reality, to promote nuclear power or smear those who oppose it.

Your ceaseless rubbish usually doesn't merit a "rebuttal".

[oldhippie]

39. No credentials

Your denouncements and non-rebuttals mean nothing to me, and they shouldn't mean anything to anyone else that is paying attention.

I'll give you one thing. You are a master propagandist. I guess I mean that as a compliment, because you are very good at what you do. Too bad it's wrong.

[PamW]

40. OK - you got me.

kristopher,

OK - you got me. Energy doesn't travel by radiation. The only way energy traverses is by conduction and convection; not radiation.

You can do the experiment for yourself. You can get a red hot iron ingot. Then you can approach the red hot iron ingot with arms outstretched holding a brick of C-4 high explosive.

Everything I say is rubbish. NOTHING is going to happen with that C-4 explosive (snicker snicker)

You are going to be perfectly OK; and will have demonstrated to the forum that I'm a complete fraud.

(Hey gang, do think he'll take the bait and go for it? He seems pretty sure of himself. snicker snicker)

PamW

[joshcryer]

24. That only considers solid fuels and therefore is irrelevant to LFTR.

http://energyfromthorium.com/ieer-rebuttal/

http://energyfromthorium.com/2010/05/13/cannaras-rebuke-of-psrieer/

I'll take Alexander Cannara's word over Arjun Makhijani, who clearly has an anti-nuclear bias.

[kristopher]

29. NPR: Is Thorium A Magic Bullet For Our Energy Problems?

FLATOW: Not everyone sees thorium reactors as cheap, clean and safe alternatives, that - as a bet for the future. With me is Dr. Arjun Makhijani. He is president of the Institute for Energy and Environmental Research. He's here in our D.C. studios. Do you agree with Richard Martin that we missed out on thorium? If we had started out with thorium, would be in better shape now?

ARJUN MAKHIJANI: I don't think so. I think the problems of nuclear power, fundamentally, would remain. The safety problems would be different. I mean, Mr. Martin and proponents of thorium are right in the sense that the liquid fuel reactor has a number of safety advantages, but it also has a number of disadvantages.

For instance, this breeder reactor lost out with the sodium-cooled breeder, in the incident that Mr. Martin mentioned, because the liquid - the molten sodium reactor, the sodium-cooled reactor has a much better breeding ratio. It produces a lot more excess fuel that you can then take to the next reactor.

...It doesn't solve the proliferation problem. It doesn't solve the waste problem, either. So every nuclear reactor, no matter what type, creates fission products, which are highly radioactive materials, some short-lived, some long-lived, to make energy.

http://www.npr.org/2012/05/04/152026805/is-thorium-a-magic-bullet-for-our-energy-problems

Here is a back and forth with Mahkijani and an advocate for the LFTR. The LFTR is more hype than 'magic bullet'.

[longship]

27. IMHO, not a practical solution.

We can have many better advances in clean energy than thorium reactors for less cost. Thorium reactors are still in the primary research stage, while there are many clean energy alternatives already in practice. With limited resources, why even consider it?

[Cleita]

28. I've seen this meme being pushed even here on DU. n/t