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.
Discover more from Watts Up With That?
Subscribe to get the latest posts sent to your email.
U233 is not considered to be ideal for fission bomb production as it is much more difficult than U235 or PU239 to handle safely. This is because in the Thorium fuel cycle U232 is co produced with U233 and when it decays it generates high energy gamma rays. This problem actually worsens progressively after separation from the spent Thorium fuel occurs.
See, for example,
http://www.torium.se/res/Documents/9_1kang.pdf
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?
———————————————————————————–
Back then–that was the Specs for Thorium. . The point of a bomber that could fly without having to land every so often was that it couldn’t be located…back then. It would be a retaliatory weapon as part of the detente of Nato. The role our submarines play today–(treasonable acts by gitts in governments aside), Now, the potential is to have a pilotless HEAVY bomber that could stay aloft for days…weeks, coupled with stealth, would have enourmous defensive and offensive uses (we already have armed Global Hawks which have some of these capabilities). .
We’ve got lots of thorium in the UK, but we don’t need it. You see we’ve got off-shore wind farms that produce electricity for a mere 25 pence (40 American cents) per kilowatt/hour. That’s right, only four times the cost of nuclear. Bargain.
John Whitman says:
August 9, 2011 at 12:59 pm
“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.”
Exactly! That is why we need to continue development now, so that corrosion problems can be identified and solved before there are 100 reactors operating. A quick look via Google is encouraging; it looks like the corrosion problems are manageable. Lets be sure before we go ahead.
The Joule process sounds interesting (see post at 10:18 am), but I see a bit of a problem of scale. I didn’t take the time to do an accurate conversion, but for every million barrels a day of fuel oil (we use over 19M barrels a day of crude, but it’s not all used as fuel) it would require about 1.5 million acres of land. That assumes 100% on line, operating at peak efficiency. There might be an issue with covering an area the equivalent of Alabama with bio-solar fields.
Compact power wins every time. Electrical energy can be converted economically into another form of energy, like hydrogen, if the power is inexpensive. If the new battery technologies can be commercialized, they will be so compact, no fossil fuels will be needed for most transportation. I believe the combination of Nuclear and battery will likely be the main source of portable power in the future. Windmills and PV make no sense to me, and ethanol from corn is criminal.
Just to make something clear about the above graphs:
Both, Uranium and Thorium reactors, produce about 1 tonne of fission products per GigaWatt/year + Transuranics. However, the amount of transuranics produced by Thorium reactors is negligible. The fission products produced by either reactor type are very similar and they are indeed initially highly radioactive. But there’s a natural law that says that the more radioactive a substance is, the faster it decays.
Of the typical fission product isotope mix, about 83% decay within one year (and the really highly radioactive ones in minutes). The remaining 17% have half-lives of about 30 years. Only very small amounts (grams) have longer half-lives. Which means after about 300-500 years of storage the remaining radioactivity of the 170 kg of longer lived fission products is lower than the ore from where the original fission fuel came from.
pochas says @John Whitman :
August 9, 2011 at 3:16 pm
“””””Exactly! That is why we need to continue development now, so that corrosion problems can be identified and solved before there are 100 reactors operating. A quick look via Google is encouraging; it looks like the corrosion problems are manageable. Lets be sure before we go ahead.”””””
——————
pochas,
Your enthusiasm is infectious. : )
However, I advise realistic expectations.
The US gov’t reshuffles due to elections every 4yrs on the average.
That is a problem for long term nuclear plant development. If the gov’t is heavily involved and is allowed intervention rights and if the ideological environmentalists do again what they did to the USA nuclear program in the 1970s and 1980s THEN WE ARE TALKING MAJOR roadblocks of an unforeseeable nature. I do not wish to be discouraging, but we need to see these things clearly to overcome them.
I would have very high optimism if I saw a fundamental shift to freer capitalistic and entrepreneurial culture; I am talking about that being officially sanctioned by 99% of both political parties. THAT IS WHAT WE NEED TO MAKE HAPPEN BEFORE embarking on a long term (and it is long term) thorium program in earnest. But with the commitment there can still be no thorium feasibility guarantees . . . the feasibility is determined after several full scale prototypes have run for a few years . . . then mass production starts.
While there are serious technical challenges in thorium plant development and testing that have no guarantees to be overcome, those are insignificant without a culture shift endorsed by 99% of both political parties and a general culture that will agree to set THE INTERVENTION THRESHOLD LEVEL THRESHOLD VERY HIGH on the ideological NGOs.
Be of good cheer, it could work.
But still if everything goes right you won’t see the first dozen plants online until at least 30 yrs from now and won’t see 100 plants online until at least 40 yrs from now.
In the interim we still the need of additional electrical supply construction independent of whether thorium actualizes. That addition interim electric power supply has to be addressed also.
John
I was just speaking with a Fermilab colleague about thorium reactors, Anthony, and he mentioned that particle accelerators can be used to improve the efficiency of the process. Fermilab will be shutting down their large “Tevitron” accelerator ring in the near future, and they are seeking a new mission for utilization of their vast knowledge in this area. It could be a winner. See:
http://www.world-nuclear.org/info/inf35.html
KLA:
are you saying that all of the shouting and screaming about long halflife radioactives and their storage and disposal in the last 50 years is about a few POUNDS of stuff.
WTF…………..
C
To put something further into perspective:
The “renewable” crowd is fond of specifying power in ” supplies x households”, while neglecting to say that this number is based on peak production capability, not actual production.
However,
A typical US household of 4 uses about 1 kW of electricity averaged over a year, or 0.25kWyear per person. For a human lifetime of 80 years the amount of thorium used in a MSR would be 20 grams per person over that persons lifetime.
The primary use of Thorium until the 1990s was in welding rods. A typical thoriated welding rod contained about 1/4 gram of Thorium, enough to supply the electrical needs for a typical American for one year!!. If you imagine a US quarter made of Thorium, then that person would use up ONE such quarter every 37 years!!
“Once the thorium reactor is adopted as the nuclear process of choice, we will be wondering why we bothered with anything else.”
Yer such a dreamer. These currently can’t built and operated economically because of plumbing problems. Generation of highly corrosive toxic radiactive byproducts in dual fluid design which destroys plumbing if it’s not removed and is too expensive to process out for economical operation. In the single fluid design nothing but graphite can be used for plumbing and it gets brittle and cracks.
Other than overcoming engineering problems with no known solution, however long that might take, and the usual 20 year wait for a new generation nuke to get certified this isn’t going to solve any energy problems. Buy a clue, please.
Charlie Foxtrot says:
August 9, 2011 at 3:23 pm
“The Joule process sounds interesting (see post at 10:18 am), but I see a bit of a problem of scale. I didn’t take the time to do an accurate conversion, but for every million barrels a day of fuel oil (we use over 19M barrels a day of crude, but it’s not all used as fuel) it would require about 1.5 million acres of land. That assumes 100% on line, operating at peak efficiency. There might be an issue with covering an area the equivalent of Alabama with bio-solar fields.”
Not a problem my friend. The Texas panhandle is suitable, it’s 20 million acres, and there ain’t nothin’ much on it now but oil wells, wind mills, and a few cattle. You could use 1.5 million acres of it and it would hardly put a dent in it.
I think you may have misread or msiheard something about the single fluid design, There are variations of monel and various ceramics that appeared to be very promising when evaluated at Oak Ridge in the early 70’s. I wasn’t directly involved, but was working on a related project. This was a common lunch room topic. I don’t think anyone involved was considering graphite piping for future commercial designs. One problem will be that most of the develpment engineers from taht project have long retired.
Charlie Foxtrot says:
August 9, 2011 at 3:23 pm
“about 1.5 million acres of land. That assumes 100% on line, operating at peak efficiency. There might be an issue with covering an area the equivalent of Alabama with bio-solar fields.”
You dropped a couple decimal points there. Alabama is over 30 million acres in size.
Other interesting facts. The Texas panhandle has one person living on it for every 150 acres. A million more employable adults would have to relocate there just to operate the sucker.
I wonder how many
illegalsdocument-challenged low skill construction workers it would take to build it out in ten years. Contrary to urban legend those workers aren’t in infinite supply ya know. It would make Hoover dam project look like a wooden bridge in Vermont by comparison.Denier says:
August 9, 2011 at 11:24 am
Pu238 is right. Larry said “space probes,” not “space bombs.”. Would you a thermoelectric source with a half life of 88 years or one heated by Pu239 with a half life of 24,000 years? (Hint – each decays with a n alpha particle with about the same energy, so you’d need 24000/88=272X more Pu239 for the same heating.) The Voyager probes outside of the solar system needed some power management reprogramming because their RTGs aren’t as young as they once were. The thermocouples also degrade.
Wikipedia has a nice photo of a Pu238 oxide pellet glowing red thanks to self heating. Yikes!
http://en.wikipedia.org/wiki/Radioisotope_thermoelectric_generator
I agree with Mr Archibald with one proviso. The proviso is that all eggs should NOT be put into the molten fluoride system basket.
After long experience with corrosive halide systems I can tell everyone that the engineering is VERY DIFFICULT, and typically the results do not meet the promises. There are very few successful molten halide systems, and none I know of which have the requirement of long term low maintenance that this system will require. (And before anyone objects Al potlines need plenty of maintenance, since pot lifetime is only about 4-10 years (and with no radioactivity blasting the materials of construction!) – which is why spent potliner is a continuing environmental thorn in their side – and that is not highly radioactive).
The Indians as I recall are continuing with a more conventional fuel element design – this is likely to be much, much more robust and idiot-proof compared with molten salt.
Does anyone know what the delayed neutron fraction is for a thorium reactor? in a U/Pu reactor most neutrons are born “prompt”, within 10^-14 seconds of the fission event (>99%). A small fraction is born delayed, via fission fragments that decay producing “delayed” neutrons (delayed neutron precursors). It is these delayed neutron precursors that make the reactor controllable by raising the neutron generation lifetime to value that allows practical control. Anyone know what the control philosophies are for a thorium reactor?
MikeinAppalachia says:
August 9, 2011 at 5:11 pm
“I think you may have misread or msiheard something about the single fluid design, There are variations of monel and various ceramics that appeared to be very promising when evaluated at Oak Ridge in the early 70′s. I wasn’t directly involved, but was working on a related project. This was a common lunch room topic. I don’t think anyone involved was considering graphite piping for future commercial designs. One problem will be that most of the develpment engineers from taht project have long retired.”
Sorry about that. I gots my single and dual fluid problems in reverse. Graphite plumbing is needed for dual fluid design. Highly corrosive chemistry is the problem in single fluid designs. Continuous processing of the molten salt to remove a variety of destructive byproducts has never been done and no known materials can stand up to it for long. You can’t build everything out of ceramics and not much can withstand the heat, the corrosives, and the neutron flux in a single material. It’s a LONG way from feasible. It doesn’t even work in a toy computer model.
Scan of 50 year-old ORNL survey of materials and associated problems:
http://www.energyfromthorium.com/pdf/FFR_chap13.pdf
This is a link to the “The Four Horsemen of the Apocalypse” presentation on the Institute of World Politics website: http://www.iwp.edu/docLib/20110630_FourHorsemen.pdf
Thorium can be used as an oxide just as uranium is today and thorium oxide has better thermal conductivity and a higher melting point. There is no need for special materials because there is no need for these to be molten salt reactors.
->Doug Bodero
Excellent question!
According to this:
http://www.reak.bme.hu/Wigner_Course/WignerManuals/Budapest/DELAYED_NEUTRON.htm
(Great paper discussing the effect of delayed neutrons on neutron flux, and reactivity.)
The delayed fraction per 100 fissions is .667 for U-233 and 1.621 for U-235, making U-233 reactor less stable.
The chart doesn’t show how much material is needed of the neutron source to irradiate the thorium in order to covert it to U-233 before it becomes fissionable.
Although it is probably much less energy than is needed to enhance U-20x to U-235.
“bair polaire says: August 9, 2011 at 9:40 am
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. ”
No. Watch the video link I posted. 83% of the waste is inert after 10 years and can be mined for valuable minerals. The other 17% is dangerous for 300 years. Combined with greatly reduced waste due to much more complete utilization of the fuel you have a clear winner.
Natural disasters and terrorism, while not impossible, are hard to figure out. In the Liquid (LFTR) design it is already molten at low pressure and goes solid if the power goes out. A simple gravity based drainage pipe system (kept solid by electricity) will melt when the power goes out and all the reactant will drain to the holding tank. They turned the power off on weekends when they went home with the 1960s test reactor.
Not perfect but darn is that an elegant design. Check out the video. Well worth the time.
Concerning spent nuclear waste, Willis E came up with the best idea I’ve seen:
http://wattsupwiththat.com/2011/05/06/a-modest-proposal-for-nuclear-waste-disposal
“”””” Dave Springer says:
August 9, 2011 at 9:59 am
Biofuel solves all our immediate problems it just needs to be more economical to produce. That’s happening as we speak. “””””
Better check the current issue of Scientific American magazine Dave.
I’m afraid the bloom has gone off bio-fuels; all bio-fuels, including microbe created ones. Bio-fuels are as big a pipe dream as fusion energy. Yes I know there are people who can make all the ethanol they need to run their auto, in their bathroom, using basically nothing. So buy their stocks, they should be pretty cheap right now.
I’d like a dollar for every time someone said their favorite alternative energy just needs to be cheaper to produce.
It has nothing at all to do with cost. Simply put a big tax on oil and natural gas; say a million dollars a barrel. So now your alternative is cheap; so have at it and get rich. Well it would have been cheap if you had purchased all the energy you needed to run your still yesterday, before I put that stupid tax on it.
If bio-fuels made sense from an energy budget point of view (don’t forget all that water you need), the Arabs would be pounding sand..