## Tuesday, March 26, 2013 ... /////

### Rosatom plans fast reactors based on U-238

Technet, a Czech sci-tech server, published an interview with Vyacheslav Pershukov today, the deputy CEO and the director of the scientific-technological complex at Rosatom, the state-owned Russian nuclear corporation that is managing all Russian reactors that are in operation.

He says many things I should have noticed half a year ago because as Russia Beyond the Headlines mentioned in November (see also an echo in The Telegraph), there was a nuclear conference in October 2012 in a city whose name is nothing else than Prague where they presented plans to build new, "fast reactors" on the Russian territory with the help of 13 Czech companies.

And they seem to be better than the nuclear technologies we are using today.

Existing nuclear power plants are using uranium-235 which is rare (we need to get this one which is what enrichment is all about) and it produces lots of long-lived radioactive waste.

To make the story short, the fast reactors (or fast-neutron reactors) are employing the nearly omnipresent uranium-238 which can be supplemented with lots of other radioactive garbage, including the radioactive waste from the contemporary nuclear reactors. It's possible because they have a different speed of the neutrons which is allowed because the moderator isn't there at all and stabilization is achieved either by Doppler broadening, thermal expansion of the fuel, a neutron poison, or a neutron reflector.

To make the story even better, some of these reactors are breeder reactors so they produce some new fuel along the way. The radioactive waste coming out of these reactors is a mixture of isotopes that only need to spend one year in the cooling swimming pools; plus plutonium and uranium-238 that may be recycled as fuel if they're properly separated. This separation procedure only exists theoretically at this point but they seem confident that it's possible.

To summarize, these reactors may use what we consider waste today; their own waste is a mixture of a new fuel and true waste that doesn't need to be stored for too long; they're more efficient; and they can't really explode because there's no water (but if the envelope breaks in the sodium-cooled reactor with thousands of tons of sodium, the reactor is finished – but safely so for humans).

The particular RBTH story focuses on the SVBR-100 lead-bismuth-cooled reactor (developed with the Czech companies) and the BN-800 reactor, a sodium-cooled fast breeder reactor, which is under construction in the Beloyarsk power plant in the Sverdlovsk region.

(Sverdlovsk is the communist name of Yekaterinburg, Pilsen's twin city in Russia: they have kept the name inspired by the heartless murderer of the tsar family for the region around the city. That surely sounds fair to our Russian brothers: if one name is after a tsaritsa, Catherina I of Russia, there must be another name derived from the killer of the tsar family. Yes, the murder of the family took place in Yekaterinburg itself. Lots of other bad things happened in our twin city. Last summer, for example, they found 4 barrels with 248 human fetuses over there. The kids could have built the adjoint representation of $E_8$ but they were terminated...)

I hope we will see the new power plants soon enough. They hope to end the research and design of SVBR-100 in 2014 and run it in 2017. Independently of that, Rosatom is planning nuclear reactors for spaceships. There are two big challenges: to get it into space and to launch it over there. They're thinking about its first big test – a mission to Mars.

Meanwhile, Westinghouse claims to be ahead of its Russian competitor in the tender to complete the (not fast) Czech Temelín nuclear power plant.

#### snail feedback (18) :

reader AJ said...

I thought thorium reactors were the way of the future? Is U-238 a better bet?

What do you think of Lockheed Skunk Work's research into compact fusion reactors? A working 100MW prototype in 5 years... sounds too good to be true, doesn't it?

https://www.youtube.com/watch?v=JAsRFVbcyUY

reader Andy Everett said...

Professor Motl, if the costs for power generation were equal between coal and nuclear would you consider the downside of burning coal to be greater then the downside of operation of this new type of reactor?

reader etudiant said...

There is considerable military experience with lead/bismuth as well as with sodium metal cooled reactors, as a result of which all have been withdrawn from service. They are very vulnerable to corrosion, so reliability was bad, even though the power density was good.

Fast reactors are very appealing, but enthusiasm should be tempered by the reality that the US, France and Japan all had flagship sodium cooled fast reactor programs that developed horrendous problems bad enough to force abandonment. It seems this type of reactor demands sustained excellence at all levels to perform safely. Bitter experience suggests current fast reactor concepts generate too fragile a design to be attractive for routine power generation, where marginal maintenance and operations are a fact of life.

reader Luna said...

The extra money spent on breeders compared to the conventional reactors can buy a lot of fuel at today's prices. So until nuclear fuel becomes particularly pricey, it will be cheaper to keep building the reactor designs that we already have.
To get electricity from the nuclear fuel, one needs both fuel and a power plant. So the costs of the two need to be optimized together, and not in isolate.

reader CIPig said...

U-238 has a fundamental problem - it's not fissile. It needs to be converted to Plutonium to be useful in reactors (or bombs). It's this latter use that makes people nervous. Details at http://en.wikipedia.org/wiki/Uranium-238

reader Rami Niemi said...

Fully agree on this one. Fuel costs are about 10% of the total costs of nuclear power these days. Real problem to focus on is the installation costs. Fusion power will come sooner than the need for fast reactors. http://en.wikipedia.org/wiki/File:MonthlyUraniumSpot.png

reader Henrik Lindgaard said...

As I see it, Thorium reactors are the future for the western world. Mainly salt-breeder reactors. I believe there is only one half-ass reason why TBR's haven't gotten more attention in Europe and the USA, and that is the possibility of producing highly pure U-233. I find it highly unlikely that pure U-233, or decaying Pa-233, will find its way into the hands of terrorists - hell, it would be easier to get other radioactive waste to use in dirty bombs.

On the other hand, the TBR beats all other reactors on almost everything - inherent safety features, as automatic draining when overheating, low pressure of the reactor vessel, solidification of escaping fluid, high heat-to-energy conversion (>40%) - but, by far the most attractive thing about the TBR, is its waste properties. If the TBR is built with a on-site pyro-processing (mainly electrolytic reactions + some purging etc.), it would produce the least spent fuel, the least harmful spent fuel in addition to a dramatic reduction in reprocessing waste.

reader JollyJoker said...

Nuclear waste has a negative price. I wouldn't be surprised if breeder reactors are the cheapest way to get rid of existing waste.

reader fer XYZ said...

"To summarize, these reactors may use what we consider waste today; "

Moreover, today it is considered "nuclear-waste" even what has about 10% of precious metals, more expensives than gold.
http://en.wikipedia.org/wiki/Synthesis_of_precious_metals
Send me that 'waste', that will store in my garden a few years. Thanks :)

reader netudiant said...

The corrosion issue was most severe in the lead/bismuth cooled reactors, the coolant reacted with the cooling pipes. Otherwise, the coolant was inert to battle damage, a major advantage over sodium.

Sodium cooling was the design basis for the French Super Phoenix and the Japanese Monju fast reactors. Both had serious leaks, but no fires because fortunately the plants were kept in an inert atmosphere. The concern is that if the installation is too fragile for the researchers to run it, what hope is there for safe operations in normal commercial use, where cost is always a constraint on maintenance.

reader . . said...

1. For the question of liquid metal and molten salt reactors, the following provides some historical information and interesting links: http://nucleargreen.blogspot.com/2010/05/msr-lmfbr-decision-reason-and-science.html

2. Of course Rossatom could also follow the path of Terrapower (http://en.wikipedia.org/wiki/TerraPower).

3. To respond to people who wrote U238 is not fissile, yes but, Fermi supposedly said: "Give me enough neutrons and I shall give you the Entire Periodic Table." That is what fast reactors and hot burn zones are all about: Getting rid of the long lived nuclear waste and burning U238 is very useful because a pile of it already exists. Reactors are definitely better use for it than ammunition.

Congratulations to the Czech companies to help advance nuclear technology.

reader HelianUnbound said...

@Henrik Lindgaard

Molten salt thorium breeders certainly look attractive, but their proponents always seem to ignore an important drawback. Flibe, by far the most attractive material for the molten salt, is highly corrosive. Even the best nickel alloys available today would not stand up to it in long term reactor operations. That is not, of course, a show stopper, and the search goes on for better alloys and alternative salts.

I don't think U-233 will be a problem in a reasonably designed thorium reactor. It can be denatured by mixing it with U-238, and will always come mixed with some highly radioactive and deadly U-232, the amount of which can be adjusted up or down by altering neutron temperature, etc. It is, of course, very suitable for making bombs in relatively pure form.

Unfortunately, none of these fast reactor types will take off without extensive government support. Industry prefers the current U-235 burners because they are more profitable. As a result, you will usually hear them claim that there is plenty of natural uranium for the foreseeable future, the transuranic actinide waste problem is a red herring, etc. These arguments do not make a lot of sense unless you understand what motivates them. It is short-sighted, and even foolhardy, to throw away most of the energy content of uranium, and irresponsible to store the actinides, which will remain dangerous for 10's of thousands of years, instead of destroying them in fast breeders, where the resulting waste could be less radioactive than the original ore in only several hundred years.

Of course, it is even more irresponsible to shut down nuclear reactors, as the Germans are doing, and replacing them with coal-fired generators. Coal contains a few parts per million each of thorium and uranium, and a good-sized one will release
about 5 tons of uranium and 10 tons of thorium each year. See, for example,

http://www.ornl.gov/info/ornlreview/rev26-34/text/colmain.html
As for fusion, it is certainly scientifically feasible, but an engineering nightmare. Add to that the fact that the National Ignition Facility at Livermore just failed to meet its ignition milestone, and ITER, the biggest white elephant in the history of science, isn't even supposed to be fueled with tritium until 2028, and it's plausibility as a viable energy source any time in the foreseeable future is very dubious. Fusion badly needs a "magic bullet" in the form of a scientific breakthrough.

reader iya said...

Thorium is not fissile either, it's "fertile", but it's not a fundamental problem, you just put it in the breeder and (with enough neutrons) it becomes fissile U233, just as U238 becomes P239 with no extra work.
Both could be used for bombs, but it's a special case of a more general development:
As mankind gets access to more powerful and energy dense technologies (another example is future space travel and industry), it's inevitably linked to more destructive potential.
Of course I don't like big government, but we should definitely be careful and think of political solutions, e.g., civilization wide checks and balances.

reader HelianUnbound said...

It's amazing how much disinformation one finds in blog comments about things nuclear, even compared to the other sciences. For example, from etudiant,

"There is considerable military experience with lead/bismuth as well as with sodium metal cooled reactors, as a result of which all have been withdrawn from service. They are very vulnerable to corrosion, so reliability was bad, even though the power density was good.

"Fast reactors are very appealing, but enthusiasm should be tempered by the reality that the US, France and Japan all had flagship sodium cooled fast reactor programs that developed horrendous problems bad enough to force abandonment."

EBR II at Idaho National Laboratory was certainly one of the US "flagship" sodium cooled fast reactors. It was not run by the military. Other than that, the claim that it "developed horrendous problems bad enough to force abandonment" is a complete fairy tale. EBR II was closed in 1994 after thirty years of safe operation for economic and political reasons having nothing whatsoever to do with "horrendous problems". By all accounts, its staff did not consist of people of superhuman abilities, but rather typical reactor operators. I work at Idaho National Laboratory. I can easily drive to the Materials and Fuels Complex, where EBR II was located at any time and talk to people there who both worked on the reactor, administered it, and were involved in its closing. I can assure etudiant that none of them has ever heard of the "horrendous problems" he refers to. The relevant literature is still in our library. It, too, will confirm that these "horrendous problems" are a complete myth.

I am nonplussed by comments like this. They can be completely exploded by spending 15 minutes on Google. Somehow, people can't be bothered, and post them anyway.

reader Gene Day said...

Yep. When I was still a student at Berkeley in 1962-3 there was a research reactor on the other side of the wall from my desk. I wasn’t worried but if it had been sodium-cooled I would have been pretty concerned. Sodium-cooled reactors are wonderfully compact and very simple to maintain unless something goes wrong. So are lithium-ion batteries, unless something goes wrong!

reader Henrik Lindgaard said...

I am a proponent of research into molten salt breeder reactors, but i do not ignore their problems - I simply didn't bring up the subject in my previous comment here (one can't write everything into one little comment). As I see it there are mainly 2 real problems with the MSR:
1. Corrosion
2. Lack of established on-site processing chain

The corrosion problem is, as you correctly put it, a drawback - until it is resolved. But just denouncing the technology, and any research into molten salt reactors, will definitely not give any solution to the problem.

reader Casper said...

One can only wonder at the folly of developing a civilian nuclear reactor program that that produces a staggering 99.5% massively toxic long lived waste from the available fuel.

But such is the almost inconceivable stupidity of American politics and its satanic puppetmaster, the US military. One can only hope that when the Angel of the Lord arises from its slumber, the persons responsible are pushed genitals first into the plutonium lake of fire.

The current system of nuclear power generation can only be described as complete and utter shit. They are the 17th century equivalent of the motor car. They are possibly even worse than wind turbines (although even burning babies for fuel would be better than wind turbines).

Lets hope that President Putrid of Russia and his array of Czech geniuses can do better. Lets hope that anybody can do better, since its clearly been technically possible to eliminate this horrifying waste and produce over 90% fuel efficiency since the 1950s.

According to the Nuclear Weapons article in Wikipedia, the US "Between 1940 and 1996, the U.S. spent at least \$8.63 trillion in present day terms on nuclear weapons development" Nevertheless they cant find the money to build a decent nuclear reactor. What a joke of a country it has become.

reader Lars C. said...

I don't want that kind of plant in my country - at least I don't want it from Russia. I guess they would start to transport the waste behind the mountains and seas.
Highways and ships full of super toxic stuff.

Sounds like a very bad idea.