Further on Thorium

While Matthew Nisbet opines on peak oil being a uniting cause, this short essay on thorium power is instructive and relevant. – Anthony

Guest post by David Archibald

Early in June, I gave a lecture entitled “The Four Horsemen of the Apocalypse” at the Institute for World Politics (a graduate school for the CIA and State Department) in Washington. From that lecture, following are a couple of slides pertaining to the advantage of thorium relative to uranium for nuclear power:


To run a 1,000 MW reactor for a year requires one tonne of nuclear material to be fissioned. In the case of thorium, only one tonne of waste material is produced with 30 to 100 grams of transuranics (Neptunium and plutonium). Alternatively, the Neptunium could be separated from the uranium and burnt separately in a reactor for that purpose, at the ratio of 49 thorium reactors per one neptunium reactor.

The very low level of transuranics from the thorium route compares to the large waste volumes and transuranic content of that waste from the uranium route, shown in the above slide. The one tonne of thorium from the first slide is shown in scale to the 250 tonnes of uranium needed to produce one 1,000 MWyear in the light water reactor route. That 250 tonnes of uranium produces 35 tonnes of enriched uranium, which becomes the spent fuel volume. Of that 35 tonnes, 300 kg is plutonium. The transuranic content of the uranium light water reactor route is some 10,000 times greater than that of the thorium route.

Once the thorium reactor is adopted as the nuclear process of choice, we will be wondering why we bothered with anything else.


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Both the US and Canada needs to move to this, quickly. Otherwise it will be something else we import from China.


Very instructive


We bothered with the uranium reactors because at the time we were in the cold war and wanted to have a quick and ready source of bomb making materials. This is the 1970s we are talking about. Thankfully, the need for a ready source of those things has vastly diminished. Hopefully as we decommission the old plants, we will replace them with thorium.

This does seem like a very promising route for energy.
The two drawbacks I see at the moment are
1) “The neutron flux from spontaneous fission of 233U is negligible. 233U can thus be used easily in a simple gun-type nuclear bomb design.”
2) “However, unlike uranium-based breeder reactors, thorium requires irradiation and reprocessing before the above-noted advantages of thorium-232 can be realized, which makes thorium fuels more expensive than uranium fuels.”
Both quotes are from Wikipedia. Cost is always a concern, but cost is also relative, and it is certainly conceivable that as the process gets refined, the processing costs will come down. The weapons-grade U-233 is a concern, but that also seems to be something that can be mitigated by appropriate designs for the reactor.
Overall, it is certainly a technology worth exploring further!

John Davis

So how many of these magical reactors are actually running? Are the paper advantages proven?


If I read this correctly, a 1 Gig Watt reactor can be done with 1/250th starting material and significantly less waste/byproduct? I’m all for it, lets study what can done with the byproduct and get these up and running.


Both the US and Canada needs to move to this, quickly. Otherwise it will be something else we import from China.

The Indians are working fast and furious on this. There are huge reserves of Th in India.

Bill Marsh

The better news is that there is enough Thorium within the US to supply our electricity needs for something like 8,000 years (which should be sufficient time for us to finally overcome the technical and engineering challenges presented by fusion).

Mark Wagner CPA

which is exactly why the gub’mint will never do it.

bair polaire

too late, too little (improvement).
The thorium route still produces nuclear waste that needs to be taken care of for millennia. The reactor sites are vulnerable to natural disasters and terrorism.
Why shall we now follow Michael Mann and James Hansen on their way to a nuclear energy future? They have been wrong before!

Unfortunately I don’t see any interest from mainstream politicians in thr West. Our political classes are tied to wind, solar and biofuels to the exclusion of anything else.

What I know about nuclear fission can fit inside a nucleus of a hydrogen atom but I got to ask some questions. If these graphs are accurate why not use thorium? What are the negatives of using thorium? Are the byproducts of a thorium reaction more poisonous, have a longer half life, harder to store than those produced from a uranium based reaction?

Dave Springer

Electricity is not a practical replacement for the majority of liquid fuel use. And it isn’t a pressing problem unless you buy into the CAGW meme where CO2 is the designated scapegoat. There’s plenty of natural gas and coal and it’s affordable and adequate for electrical generation. What we need is a compatible, LESS EXPENSIVE alternative to fossil gasoline, diesel, and kerosene at least in great enough quantity so we don’t need imports. That will stimulate the economy like nothing else.
I trace the current economic funk back to roots in 2005 where over the next three years the price of oil went from $40/bbl to $140/bbl. That’s gotta end. Notice it’s happening again with oil at $120/bbl after a few years respite and, lo and behold the financial crisis got its second wind this week. Coincidence? I don’t think so. We’re getting played like a fiddle.

Grumpy Old Man

Excellent stopgap until we crack cold fusion.


I look forward to anti-nuclear types babbling about thorium bombs.

Brian Johnson uk

Had the Tsunami hit Japanese Thorium reactors [not Uranium ones] there would have been no emergency and it is only the desire for Nuclear Weapons manufacture that led the Cold War opponents to avoid using Thorium being too safe, too stable, highly efficient, low waste and much less complex/expensive machinery. There is masses of Thorium available……….it may be more expensive than Uranium but almost all Thorium is used [with almost no waste] as opposed to very little Uranium actually used and massive waste problems.
It is staring the politicians in the face and they are blind to its potential for almost limitless power and the ability to produce compact versions for outlying civilisations without ugly pylons everywhere.

Coach Springer

Is this another of those 20 years away technologies? I know it was 20 years ago.
No one will stop you until you get close, then Big Green will take an interest, at first suport it, and then treat it like coal. In the long run, we could be getting free energy from bananas and they would oppose it for the radioactivity in bananas. It’s inevitably precautionary. We are prepared to pat them on their hands and bop them on their noses with a rolled up newspaper. They are prepared to kill us if necessary. Just give us something real – if you can – and we’ll have it out with them one way or another.

Jim Cole

How many nuclear engineers and physicists are we training in our US universities?
Yeah, that’s what I was afraid of.
Better tap the Cold War geezers before they’re all gone


All these variations use the word “nuclear,” so environmentals will deem them “evil.”

Dave Springer

Biofuel solves all our immediate problems it just needs to be more economical to produce. That’s happening as we speak. Synthetic biology is where it’s at. It’s near term and a perfect solution. No one is going to invest in a new generation of nukes if they are going to get obsoleted by genetically modified algae that drink municipal waste water and piss gasoline. Such organisms are already alive and patented. The US is, of course, leading the world in this. We innovate and others duplicate. Nothing has changed.


” John Davis says: August 9, 2011 at 9:24 am
So how many of these magical reactors are actually running? Are the paper advantages proven? ”
Yes in the 1960s they ran one for 5 years!
– Liquid Fluoride Thorium Reactor


We bothered with the uranium reactors because at the time we were in the cold war and wanted to have a quick and ready source of bomb making materials. This is the 1970s we are talking about.
Also consider before that. Uranium was a strategic issue in WW2. Before WW2, the Rockefeller dynasty had been hard at work for decades looking for ways create an economy for uranium and other radioactives they had a monopoly on.
Thorium didn’t figure in their plans for the same reason it doesn’t today. Much harder to monopolise ‘cos it’s more abundant world wide, doesn’t require expensive (& therfore exclusive ) technology to utilise, and not the best radioactive for bombs.
If big government is against nulcear power from Uranium because it provides cheap wealth indiscrimantly to the masses, then they’ll fight tooth and nail if need be to stop thorium power ever taking root in society.

I agree that the thorium route is attractive. I have always been of the opinion that the best route for uranium reactors is a heavy water design run as a breeder to make plutonium, which can then be reused. This route provides more fuel as a byproduct than you put in. The downside of course is the level of transuranics that need to be handled during the reprocessing step to extract the plutonium.

Dr T G Watkins

Check out Energy from Thorium, Kirk Sorensen’s site, for all the information needed on Liquid Fluoride Thorium Reactors. LFTRs need to be brought to the attention of politicians.

Loopy Larry

I prefer whichever makes the most Pu 238 for space probes.


The government and the Greens don’t *want* us to have lots of energy. They want to shut us down. Once people start thinking about thorium, expect a veritable flood of scorn and lies to be poured upon it.


The big negative of the Thorium reactor is the fact that it isn’t far beyond the scale of theory and some data won in experimental environments in the 1960s. You may want to research liquid salt thorium reactors to get a better picture of what it is about.
As far as fissile waste goes, there’s the option to build specialized thorium based reactors to break those further down (and even gain energy from the process). Proliferation is a very small risk since the U-233 is in solution within salts that have to stay at above 500 C to remain liquid, which makes tapping in and stealing them very complicated.

I think someone sent me a note to a slide set about a joint US/India Thorium project, I don’t have that handy here at work. I was glad to see it’s not completely ignored here in the US but remain appalled there’s so little development going on.
On my Rossi post, gallopingcamel mentions http://energyfromthorium.com/
China is pursuing Thorium reactors, and they’re certainly quite motivated to do so, I’d expect them to be the early adopter of commercial scale reactors. See http://wattsupwiththat.com/2011/01/30/china-announces-thorium-reactor-energy-program-obama-still-dwelling-on-sputnik-moments/

Dave Springer

Speaking of patented GM organisms for biofuel production I haven’t checked on Joule Unlimited in several months. As it turns out they were granted two patents on ethanol producers. These compliment similar patents granted last year for diesel producers.

Joule Awarded Patents for High Volume Ethanol Production from Sunlight and CO2
Cambridge, Mass. – July 26, 2011 – Joule Unlimited Technologies today announced the issuance of its first two U.S. patents covering its fundamental method for producing ethanol at volumes and efficiencies far surpassing biomass-dependent processes.

Read more
These aren’t incremental improvements in existing technology like a new generation of nukes or slight improvements in production costs for ethanol from corn or beets or diesel from jopthra berries. These represent leaps of an order of magnitude in downward cost and scalability. The best part is that’s just the beginning. There’s another order of magnitude improvement to be had as synthetic biology is still in it’s infancy but charging forward in a way that reminds me of the first transisters.


Oak Ridge National Laboratory explored Molten Salt Reactor design back during 1960-1976, downloadable copies of their reports are available from the Energy from Thorium site. Charles Barton’s site The Nuclear Green Revolution has articles on the history of why the MSR was ignored by the politicians.
It should be noted that MSRs can use either uranium or thorium based fuel salts, and can be tuned to “burn up” the non-useful actinides generated by the decay cycle. The MSR and its derivatives are better (safer and potentially much cheaper) than the Light Water Reactors we use today. But the Nuclear Regulatory Agency has never approved a new reactor design in its entire history, so there is a big regulatory hurdle to get over. While the ORNL research proved the physics and made advances in material selection, it did not result in a ready to approve reactor, so another iteration of research is needed.


I’m afraid the weakest point of this technology is presence of U233 at early stage of the cycle. Having one such plant Iran would not need to invest insane money into their uranium enriching programs, they’d just plug a chemical separation machine to the reactor.


This is the video (google Tech Talks) that convinced me that Thorium needs to have a reasonable (funding) chance versus “renewables”:


I fully support Thorium reactor research and implementation. But what’s with all the depleted uranium that is shown as made in chart number 2? Is this all just waste, or is there more energy that can be gathered from it? Depleted uranium can be used for military applications, but loose bits of it afterwards still have a toxicity problem even after the battles are over.


Nevermind. I misread the chart — that’s from Uranium plants.

Charlie Z

Anyone seriously interested in solving our future energy needs with a technology that is readily attainable, perpetually plentiful, sufficiently safe, and ultimately inexpensive must look at and understand the potential of LFTRs. We were on our way fifty years ago, but building bombs was too important at the time. Today, this is the only real answer that we know will work.


We’ve discussed Thorium at WUWT before. Last year. It’s initial Development Specs was to be built to fit inside a large bomber which could stay aloft indefinately. A working model was developed which ran nicely but didn’t fit any near inside a bomber. It ran without problems, was unplugged on Friday PM and when they came into work monday, re-plugged it in and off it went (with some freezing and thawing of a regulating medium). Will the Chinese find a way to fit it into a bomber…….that should cause a stir some where. The US Answer is no. But then, that asumes (or rather ass-u-mes) we know everything. The world is going to run on Thorium and we’ve already sold the reactor design and technology to the Indians and the Chinese. We tossed it aside because we couldn’t weaponize the fuel back in the 50’s. Every municipality, medium to large sized plants, aircraft carriers, trains, and perhaps first strike bombers will have one some day although it is not completely glitch free at the moment.


There is a website for the technology.


@Loopy Larry
I think you mean Pu239 (‘bomb material’ – think Trinity & ‘Fat Man’ [Nagasaki]). 238 is an alpha emitter with a half-life of *only* 87.7 years.
I know of some constructors of U – reactors who will fight tooth & nail to preserve 70 years (many, many man-years) of experience. Oh, and don’t forget the patents!


We need a commercial size demonstration plant in operation to get experience. Also the fuel reprocessing steps. Not located in earthquake or flood zones. Or on top of volcanos.

Crispin in Waterloo

bair polaire says:
>The thorium route still produces nuclear waste that needs to be taken care of for millennia.
Apparently not so. Everywhere I read they are talking about 300 years. It is not like Uranium fuelled processes.


You won’t see much action on this in the USA.
The current administration has put in place regulators that squelch all but their favorite pet projects like windmills. Even the chairman of the NRC, Jaczko, is not pro-nuke. If you go over his resume, you’ll see he began his Washington, D.C., career as a congressional science fellow in the office of U.S. Rep. Edward Markey. Markey is about as anti-nuke (and anti-industry) as it gets. No way would he have Jackzo on his staff if he didn’t share his views.


Johnnythelowery says:
August 9, 2011 at 11:04 am
What’s the point in having a bomber stay up indefinitely? They still need to land to fill-up with bombs, don’t they?


There is an excellent article about thorium nuclear power in a past issue of the American Scientist.
This way nuclear power has evolved shows how rigid people can be. There is a reluctance to consider alternate options once momentum builds behind a practice. The ‘quick’ start up path for uranium based nuclear power put thorium off partly because there was a cold war era demand for bombs.

John Whitman

I think if one is considering the primary coolant to be molten salts you have a very challenging materials problem and design problem for all the system components in the primary system and for the reactor vessel with its internal structure. Water has been a significantly challenging primary coolant for the current LWRs operating around the world. Comparing to water, molten salts are a very severe environment for all the system materials. Not the least challenge for primary system and reactor vessel using molten salts as a primary coolant is the much more intensive corrosion with the associated issue of transport of irradiated system materials being transported after they corrode. The materials needed are not yet even being extensively tested. That would need years to complete before full scale prototypes are built to determine feasibility.
The materials development for use in molten salt environment is just the example of one significant challenge.
Be realistic. If they are proven to be feasible in a couple of full scale prototypes running for say 3 yrs only then are we talking about starting to engage in mass production of full scale thorium reactors. Then we are talking minimum 20 to 25 years from now having online and at full power just the first dozen or so. For a 100 such then another 10 to 20 years beyond that. We are talking minimum 30 yrs to first dozen. 40 year from now for the first 100.
There is still a major alternate electrical power supply problem to keep up with current growth until 30 to 40 yrs from now we if is potentially possible for thorium molten salt reactors to make contribution. That is predicated on the molten salt thorium reactors being demonstrated as feasible in a couple of full scale units running for about 3 yrs. The certainty that they will be feasible is still unknown.

D. J. Hawkins

bair polaire says:
August 9, 2011 at 9:40 am
too late, too little (improvement).
The thorium route still produces nuclear waste that needs to be taken care of for millennia. The reactor sites are vulnerable to natural disasters and terrorism.
Why shall we now follow Michael Mann and James Hansen on their way to a nuclear energy future? They have been wrong before!

See @ Crispin in Waterloo above re longevity. Even if that weren’t true, the volume reduction is a winner out of the gate. It also depends on what half-lives you want to use as your benchmark. If uranium waste is nasty out to 100K years, well we’ve already bought that ticket. So what’s 100K years plus another 1K years or so in the scheme of things?

On the basis of personal recollection, the Thorium fuel cycle was considered the most viable power generation route in the years immediately following World War II. Like other kids who grew up reading the “boys’ books” Robert A. Heinlein produced for Scribners during the late ’40s and 1950s, I vividly recall that in Rocket Ship Galileo (1947), the author posited a reaction drive employing a Thorium pile to heat metallic zinc to its gaseous phase as a propellant.
As other posters here have observed, the Uranium fuel cycle was favored in significant part because the commercial use thereof “blended” with the federal government’s efforts to obtain weapons-grade fissile materials. There is little – effectively no – such characteristic in the Thorium fuel cycle.
Those of a peaceable disposition consider that a benefit.


Brian Johnson uk says:
August 9, 2011 at 9:53 am
“Had the Tsunami hit Japanese Thorium reactors [not Uranium ones] there would have been no emergency”
And if the operators had not freaked out over the radical drop in the containment vessel pressure as the automatics for the reactor scrammed due to the quake, and manually secured the emergency shutdown system, there might not have been a disaster when the tsunami arrived.