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  • Polyanna Pinker’s Power Profundities

    Posted on October 10th, 2018 Helian No comments

    Recently Steven Pinker, public intellectual and author of a “history” of the Blank Slate debacle that was largely a fairy tale but at least drew attention to the fact that it happened, has been dabbling in something entirely different. Inspired by the latest UN Jeremiad against climate change, he has embraced nuclear power. In a series of tweets, he has endorsed articles advocating expanded reliance on nuclear power, such as one that recently turned up at Huffpo cleverly entitled “If We’re Going To Save the Planet, We’ve Got To Use the Nuclear Option.” As things now stand, that would be a dangerous, wasteful, and generally ill-advised idea.

    I say “as things now stand.” I’m certainly not opposed to nuclear power. I’m just opposed to the way it would be implemented if we suddenly decided to build a bevy of new nukes given current economic realities.  The new reactors would probably look like the AP1000 models recently abandoned in South Carolina. Such reactors would use only a fraction of the available energy in their nuclear fuel, and would produce far larger amounts of long-lived radioactive waste than necessary. They are, however, cheaper than alternatives that could avoid both problems using proven technologies. Given the small number of players capable of coming up with the capital necessary to build even these inferior reactors, there is little chance that more rational alternatives will be chosen until alternative sources of energy become a great deal more expensive, or government steps in to subsidize them. Until that happens, we are better off doing without new nuclear reactors.

    As noted above, the reasons for this have to do with the efficient utilization of nuclear fuel, and the generation of radioactive waste.  In nature there is only one potential nuclear fuel – Uranium 235, or U235. U235 is “fissile,” meaning it may fission if it encounters a neutron no matter how slow that neutron happens to be traveling.  As a result, it can sustain a nuclear chain reaction, which is the source of nuclear energy. Unfortunately, natural uranium consists of only 0.7 percent U235. The rest is a heavier isotope – U238. U238 is “fissionable.” In other words, it will fission, but only if it is struck by a very energetic neutron. It cannot sustain a fission chain reaction by itself.  However, if U238 absorbs a neutron, it becomes the isotope U239, which quickly decays to neptunium 239, which, in turn, quickly decays to plutonium 239. Plutonium 239 is fissile. It follows that if all the U238 in natural uranium could be converted to Pu239 in this way, it could release vastly more energy than the tiny amount of U235 alone. This is not possible in conventional reactors such as the AP1000 mentioned above. A certain amount of plutonium is produced and burned in the fuel elements of such reactors, but the amount is very small compared to the amount of available U238. In addition, other transuranic elements, such as americium and curium, which are produced in such reactors, along with various isotopes of plutonium, would remain dangerously radioactive for thousands of years.

    These problems could be avoided by building fast breeder reactors. In conventional reactors, neutrons are “thermalized” to low energies, where the probability that they will react with a fuel nucleus are greatly increased. The neutron spectrum in “fast” reactors is significantly hotter but, as a result, more neutrons are produced, on average, in each encounter. More neutrons means that more Pu239 can be produced without quenching the fission chain reaction.  It also means that the dangerous transuranic elements referred to above, as well as long lived fission products that are the source of the most long-lived and dangerous radioactive isotopes in nuclear waste, could be destroyed via fission or transmutation. As a result, the residual radioactivity resulting from running such a nuclear reactor for, say 30 years, would drop below that released into the environment by a coal plant of comparable size in 300 to 500 years, as opposed to the thousands of years it would take for conventional reactors. And, yes, radioactivity is released by coal plants, because coal contains several parts per million each of radioactive uranium and thorium.  Meanwhile, a far higher percentage of the U238 in natural uranium would be converted to Pu239, resulting in a far more efficient utilization of the fuel material.

    An even better alternative might be molten salt reactors. In such reactors, the critical mass would be in liquid form, and would include thorium 232 (Th232) in addition to a fissile isotope.  When Th232 absorbs a neutron, it decays into U233, another fissile material.  Such reactors could run at a lower neutron “temperature” than plutonium breeders, and would be easier to control as a result.  The liquid core would also greatly reduce the danger of a nuclear accident. If it became too hot, it could simply be decanted into a holding pan where it would immediately become subcritical. Thorium is more abundant than uranium in nature, so the “fuel” material would be cheaper.

    Consider the above in the context of the present. Instead of extracting the vast amounts of energy locked up in U238, or “depleted” uranium, we use it for tank armor and armor piercing munitions. In addition to this incredibly stupid waste of potentially vast energy resources, we dispose of huge amounts of it as “radioactive waste.”  Instead of treasuring our huge stores of plutonium as sources of carbon-free energy, we busy ourselves thinking up clever ways to render them “safe” for burial in waste dumps.  It won’t work.  Plutonium can never be made “safe” in this way. Pu239 has a half-live of about 25,000 years.  It will always be possible to extract it chemically from whatever material we choose to mix it with.  Even if it is “reactor grade,” including other isotopes of plutonium such as Pu240, it will still be extremely dangerous – difficult to make into a bomb, to be sure, but easy to assemble into a critical mass that could potentially result in radioactive contamination of large areas. Carefully monitored breeder reactors are the only way of avoiding these problems.

    According to the Huffpo article referenced above,

    Doesn’t nuclear power contribute to nuclear weapons proliferation? No. Weapons programs do not depend on civilian nuclear power, which operates under stringent international safeguards.

    Really? Will the “stringent international safeguards” last for the 25,000 years it takes for even half the plutonium waste produced by conventional reactors to decay? I would advise anyone who thinks it is impossible to fabricate this waste into a bomb, no matter what combination of isotopes it contains, to take an elementary course in nuclear engineering. The only way to avoid this problem is to burn all the plutonium in breeder reactors.  Predictably, the article doesn’t even mention the incredible wastefulness of current reactors, or the existence of breeder technology.

    It’s nice that a few leftist “progressives” have finally noticed that their narrative on nuclear power has been controlled by imbeciles for the last half a century. I heartily concur that nuclear energy is a potent tool for reducing carbon and other greenhouse gas emissions.  I simply suggest that, if we decide to return to nuclear, we either provide the subsidies necessary to implement rational nuclear technologies now, or wait until it becomes economically feasible to implement them.

  • Whither Nuclear Power? A Few Comments on Thorium and the End of the “Nuclear Renaissance”

    Posted on September 2nd, 2017 Helian No comments

    About a decade ago there was much talk of a “nuclear renaissance” amid concerns about greenhouse gas emissions and the increasing cost of fossil fuel alternatives.  The Nuclear Regulatory Commission received applications to build no less than 31 new nuclear plants as the price of crude oil spiked to over $140 per barrel.  Now, however, with last month’s decision by SCANA Corp. to abandon the V. C. Summer project, a pair of nukes that had been under construction in South Carolina, nuclear’s future prospects look dim, at least in the United States.  Two plants remain under construction in Georgia but, like the ones abandoned in South Carolina, they are to be AP1000s, designed by Westinghouse.  Westinghouse filed for bankruptcy in March.  Delays and massive cost overruns similar to those that led to the demise of V. C. Summer also afflict the Georgia project, and its future seems doubtful at best.

    In short, the dream of a nuclear renaissance has evaporated.  For the time being, at least, nuclear in the U.S. is no match for more agile competitors like wind, solar, and natural gas.  However, there may be a silver lining to this cloud.  Plants like Westinghouse’s AP1000 waste most of the energy in their nuclear fuel, creating massive amounts of avoidable radioactive waste in the process.  To the extent that it makes sense to build nuclear plants at all, these are not the kind we should be building.  To understand why this is true it is first necessary to acquire some elementary knowledge about nuclear physics.

    The source of the energy produced in the core of nuclear reactors is a nuclear fission chain reaction.  Only one material that exists in significant quantities in nature can sustain such a chain reaction – uranium 235, or U235.  U235 is an isotope of uranium.  Isotopes of a given element consist of atoms with the same number of positively charged protons in their central core, or nucleus.  Like all other isotopes of uranium, U235 has 92.  There are also 143 neutrally charged neutrons, making a total of 235 “nucleons.”  Natural uranium consists of only about 0.7 percent U235.  Almost all the rest is a different isotope, U238, with a nucleus containing 146 neutrons instead of 143.

    When we say that U235 can sustain a nuclear chain reaction, we mean that if a free neutron happens to come within a very short distance of its nucleus, it may be captured, releasing enough energy in the process to cause the nucleus to split into two fragments.  When this happens, more free neutrons are released, that can then be captured by other uranium nuclei, which, in turn, fission, releasing yet more neutrons, and so on.  As noted above, U235 is the only naturally occurring isotope that can sustain such a nuclear chain reaction.  However, other isotopes can be created artificially that can do so as well.  The most important of these are U233 and plutonium 239, or Pu239.  They are important because it is possible to “breed” them in properly designed nuclear reactors, potentially producing more usable fuel than the reactor consumes.  U233 is produced by the reactions following absorption of a neutron by thorium 232, or Th232, and Pu239 by those following the absorption of a neutron by U238.  In other words, we know of three practical types of nuclear fuel; U235, U233 and Pu239.  The first occurs naturally, and the other two can be readily “bred” artificially in nuclear reactors.

    Let’s consider what this means in the case of conventional nuclear reactors like the Westinghouse AP1000.  These are powered by fuel elements that typically are enriched in U235 from the naturally occurring 0.7 percent to from three to five percent.  The remaining 95 to 97 percent of the uranium in these fuel elements is U238.  When the fission process starts, some of the neutrons released are captured by the U238, eventually resulting in the production of Pu239.  Some of this plutonium fissions along with the U235, contributing to the total energy produced by the fuel elements.  However, only a small fraction of the U238 is converted to Pu239 in this way before the fuel is consumed and it becomes necessary to replace the old fuel elements with fresh ones.  In addition to a great deal of U238, these spent fuel elements contain a significant amount of plutonium, as well as other transuranic elements such as americium and curium, which can remain dangerously radioactive for thousands of years.  The “waste” plutonium might even be used to produce a nuclear weapon.

    Obviously, if possible it would be better to extract all the energy locked up in natural uranium rather than just a small fraction of it.  In fact, it is possible, or very nearly so.  Breeder reactors are feasible that could burn nearly all the U238 in natural uranium as well as the U235 by converting it into Pu239.  In the process they could destroy much of the transuranic waste that is the main source of radioactive danger from spent fuel.  In as little as 500 years the residual radioactivity from running a nuclear plant for 30 years could potentially be less than that of the original naturally occurring uranium.  Unfortunately, while all this is scientifically feasible, it is not economically feasible.  It won’t happen without massive government subsidies.  Perhaps such subsidies are warranted in view of the threat of climate change and perhaps not, but, regardless, breeder reactors won’t be built without them.  Since they are really the only types of reactors it makes sense to build, we would probably be better off, at least for the time being, building no reactors at all.  That’s the “silver lining” I referred to above.  Perhaps a time will come when the world runs out of expendable sources of base load electrical power, such as oil, coal and natural gas, and no way has been found to take up the slack with renewables.  In that case, it may once again make economic sense to build breeder reactors.  Until that time, the United States would do well to build up a healthy stockpile of uranium, and put a stop to the stupid, wasteful, and counterproductive use of depleted uranium that could potentially become a source of vast amounts of energy to produce munitions and armor.

    But wait, there’s more!  What about thorium?  Thorium by itself can’t sustain a nuclear chain reaction.  It can, however, be converted into U233 by neutron absorption, and that is an ideal reactor fuel.  Among other things, it generates more neutrons per fission at lower neutron “temperatures” than either Pu239 or U235.  That means that extra neutrons are available to “breed” fuel at those lower temperatures where nuclear reactors are easier to control.  By “temperature” here, we’re referring to the average speed of the neutrons.  The slower they are, the more likely they are to be absorbed by a nucleus and cause fission reactions.  Neutrons are slowed in “moderators,” which can be any number of light types of atoms.  The most common is plain water, consisting of the elements hydrogen and oxygen.  Think of a billiard ball hitting another billiard ball head on.  It comes to a complete stop, transferring its energy to the other ball.  The same thing can happen with neutrons and the proton nucleus of hydrogen atoms, which are of approximately equal mass.  To breed plutonium effectively, reactors must be run at significantly higher neutron temperatures.

    There’s more good news about thorium.  It can be dissolved in various exotic mixtures and breed U233 in a reactor with a liquid instead of a solid core.  This would have a number of advantages.  In the first place, a “meltdown” would be impossible in a core that’s already “melted.”  If the core became too “hot” it could simply be drained into a holding pan to form a subcritical mass that would quickly cool.  It would also be possible to extract waste fission products and introduce fresh fuel, etc., into the core “on the fly.”  As a result the reactor would be able to stay in operation longer between shutdowns for maintenance and refueling.  The necessary technology has already been demonstrated at places like Oak Ridge, Tennessee and Shippingport, Pennsylvania.  Recently, a Dutch team finally began experiments with molten salt technology intended to take up where these earlier experiments left off after a hiatus of more than 40 years.

    Perhaps thorium’s biggest problem is the tendency of its proponents to over-hype its promise.  It even has a founding myth based on bogus claims that thorium technology isn’t dominant in the energy industry today because “it’s much harder to weaponize.”  For example, according to the article about the Dutch experiments linked above, entitled, ‘Safer’ thorium reactor trials could salvage nuclear power,

    But, if it’s so safe and reliable why hasn’t thorium been used all along? Because (unlike uranium) it’s much harder to weaponize. As a result, it’s historically been sidelined by nations in search of both energy and a potential source of weapons-grade plutonium.

    This yarn about a benign source of energy that might have benefited all mankind being torpedoed by evil weaponeers might sound good, but it’s complete nonsense.  Thorium itself can’t be weaponized, because it can’t sustain a nuclear chain reaction on its own.  The sole reason there’s any interest in it at all as a source of nuclear power is the possibility of transmuting it to U233.  Of course, it can’t be used to produce weapons-grade plutonium.  However, there is no better material for making nuclear bombs than U233.  As is the case with Pu239, four kilograms is sufficient to make a nuclear weapon, compared to the 25 kilograms that is a sufficient quantity of U235.  It’s main drawback as a weapons material is the fact that small amounts of U232 are produced along with it in thorium-based reactors, and U232 decays into radioactive daughters that are deadly sources of powerful gamma rays.  However, the amount of U232 produced can be reduced dramatically by cooling the neutron spectrum to a low “temperature.”  In short, thorium could definitely be used to make weapons.  The reason it isn’t the dominant technology for that purpose is the same as the reason it isn’t the dominant technology for producing electric power; it would be significantly more complex and expensive than using natural or slightly enriched uranium as a fuel.  That reason is as valid now as it was in the days of Little Boy and Fat Man.  The “dominant technology” would be the same as it is today whether nuclear weapons had ever been produced or not.

    When it comes to the technology itself, thorium proponents also tend to be coy about mentioning problems that don’t afflict other reactor types.  For example, the materials needed for practical molten salt reactors are extremely corrosive.  There has been progress towards finding a metal that can hold them, but no ideal alloy has yet been found.  This isn’t necessarily a show stopper, but it’s not an insignificant problem, either.  Such material issues have been largely solved for conventional reactors.  If, as would seem to be the case, these are no longer economically competitive with their rivals, then molten salt is pretty much out of the question, at least for the time being.  It’s important to point out that, if breeder reactors ever do become economically feasible again, it will always be necessary to insure that they are secure, and that the materials they produce can’t be diverted for making weapons.  That concern applies to both plutonium and thorium breeders.

    Meanwhile, it might behoove our political leaders to consider the question of why it was once possible to build more than 50 experimental reactors at what is now Idaho National Laboratory alone in a relatively short period of time for a small fraction of what similar reactors would cost today.  Merely negotiating the regulatory hurdles for building a power reactor based on anything as novel as the thorium fuel cycle would take the better part of a decade.  All these hurdles have been put in place in the name of “safety.”  That begs the question of how “safe” we will be if we lack reliable sources of electric energy.  There is a point beyond which excessive regulation itself becomes unsafe.

  • The United States’ Nuclear Future

    Posted on February 23rd, 2014 Helian No comments

    There are lots of great ideas out there for improving the way we do nuclear power.  For instance, Transatomic Power recently proposed a novel type of molten salt reactor (MSR).  The Next Generation Nuclear Plant (NGNP) Industry Alliance, with support from the U.S. Department of Energy, has chosen a high temperature gas reactor (HTGR) as its reactor of the future candidate.  Small modular reactors (SMRs) are all the rage, and a plethora of designs have been proposed.  Unlike the others, Terrapower’s traveling wave reactor (TWR), which is backed by Bill Gates, actually has a fighting chance to be built in the foreseeable future – in China.  With the possible exception of SMR’s, which have strong military support, the chances of any of them being built in the United States in the foreseeable future are slim.  Government, the courts, and a nightmarish regulatory process stand in the way as an almost insuperable barrier.

    It wasn’t always this way.  A lot of today’s “novel” concepts are based on ideas that were proposed many decades ago.  We know they work, because demonstration reactors were built to try them out.  More than a dozen were built at Oak Ridge National Laboratory in Tennessee.  No less than 53 were built at Idaho National Laboratory!  Virtually all of them were completed more than half a century ago.  There are few historical precedents that can match the sudden collapse from the vitality of those early years to the lethargy and malaise prevailing in the nuclear industry today.  It’s sad, really, because the nuclear plants that actually are on line and/or under construction are artifacts of a grossly wasteful, potentially dangerous, and obsolete technology.

    The light water reactors (LWRs) currently producing energy in this country use only a tiny fraction of the energy available in their uranium fuel, producing dangerous transuranic actinides that can remain highly radioactive for millennia in the process.  Many of the new designs are capable of extracting dozens of times more energy from a given quantity of fuel than LWRs.  Molten salt reactors would operate far more efficiently, could not melt down, and would consume dangerous actinides in the process, leaving such a small quantity of waste after several decades of operation that it would be less radioactive than the original ore used to fuel the reactor after a few hundred years rather than many millennia.  Besides also being immune to meltdown, HTGRs, because of their much higher operating temperatures, could enable such things as highly efficient electrolysis of water to produce hydrogen fuel and greatly improved extraction techniques for oil and natural gas from shale and sand.  Why, then, aren’t we building these improved designs?

    It’s highly unlikely that the necessary initiative will come from industry.  Why would they care?  They’re in the business to make a profit, and LWRs can be built and operated more cheaply than the alternatives.  Why should they worry about efficiency?  There’s plenty of cheap uranium around, and it’s unlikely there will be major shortages for decades to come.  Ask any industry spokesman, and he’ll assure you that transuranic radioactive waste and the potential proliferation issues due to the plutonium content of spent LWR fuel are mere red herrings.  I’m not so sure.

    In other words, strong government leadership would be needed to turn things around.  Unfortunately, that commodity is in short supply.  The current reality is that government is a highly effective deterrent to new reactor technology.  Take the Nuclear Regulatory Commission (NRC) for example.  Read Kafka’s The Trial and you’ll have a pretty good idea of how it operates.  So you want to license a new reactor design, do you?  Well, most of the current regulations apply specifically to LWRs, so you’ll have to give them time to come up with new ones.  Then you’ll need to spend at least a decade and millions of dollars explaining your new technology to the NRC bureaucrats.  Then you can expect an endless stream of requests for additional information, analysis of all the threat and failure scenarios they can dream up, etc., which will likely take a good number of additional years.  After all, they have to justify their existence, don’t they?  If you ever manage to get past the NRC, the court system will take things up where they left  off.

    What to do?  I don’t know.  It really doesn’t upset me when reactors built with legacy technology are pulled off line, and replaced with fossil fueled plants.  They just waste most of their fuel, throwing away energy that future generations might sorely miss once they’ve finally burned through all the coal and oil on the planet.  Maybe the best thing to do would be to just buy up all the available uranium around and wait.  We might also stop the incredibly block-headed practice of converting all of our “depleted” uranium into ammunition.  The Lone Ranger’s silver bullets were cheap by comparison.  Future generations are likely to wonder what on earth we were thinking.

    Things were a lot better in the “apathetic” 50’s, but the novelist Thomas Wolfe had it right.  You can’t go home again.

     

  • New Reactors in the UK and the Future of Nuclear Power

    Posted on October 22nd, 2013 Helian 2 comments

    A consortium led by France’s EDF Energy, including Chinese investors, has agreed with the government of the UK on terms for building a pair of new nuclear reactors at Hinkley Point in the southwest of the country, not far from Bristol.  If a final investment decision is made some time next year, and the plants are actually built, they will probably be big (about 1600 Megawatts) pressurized water reactors (PWR’s) based on the French company Areva’s EPR design.  These are supposed to be  (and probably are) safer, more efficient, and more environmentally friendly than earlier designs.  In general, I tend to be pro-nuclear.  I would certainly feel a lot safer living next to a nuclear plant than a coal plant.  However, I’m a bit ambivalent about these new starts.  I think we could be a lot smarter in the way we implement nuclear power programs.

    Reactors of the type proposed will burn uranium.  Natural uranium consists mostly of two isotopes, U235 and U238, and only U235 can be burnt directly in a nuclear reactor.  Why?  The answer to that question depends on something called “the binding energy of the last neutron.”  Think of a neutron as a bowling ball, and the nucleus of a uranium atom as a deep well.  If the bowling ball happens to roll into the well, it will drop over the edge, eventually smacking into the bottom, and releasing the energy it acquired due to the acceleration of gravity in the process.  The analogous force in the nucleus of a uranium atom is the nuclear force, incomparably greater than the force of gravity, but it acts in much the same way.  The neutron doesn’t notice this very short range force until it gets very close to the nucleus, or “lip of the well,” but when it does, it “falls in” and releases the energy acquired in the process in much the same way.  This energy is what I’ve referred to above as “the binding energy of the last neutron.”

    When this binding energy is released in the nucleus, it causes it to wiggle and vibrate, something like a big drop of water falling through the air.  In the case of U235, the energy is sufficient to cause this “liquid drop” to actually break in two, or “fission.”  Such isotopes are referred to as “fissile.”  In U238, the binding energy of the last neutron alone is not sufficient to cause fission, but the isotope can still actually fission if the neutron happens to be moving very fast when it hits the nucleus, bringing some of its own energy to the mix.  Such isotopes, while not “fissile,” are referred to as “fissionable.”  Unfortunately, the isotope U235 is only 0.7 percent of natural uranium.  Once it’s burnt, the remaining U238 is no longer useful for starting a nuclear chain reaction on its own.

    That would be the end of the story as far as conventional reactors are concerned, except for the fact that something interesting happens to the U238 when it absorbs a neutron.  As mentioned above, it doesn’t fission unless the neutron is going very fast to begin with.  Instead, with the extra neutron, it becomes U239.  However, U239 is unstable, and decays into neptunium 239, which further decays into plutonium 239, or Pu239.  In Pu239 the binding energy of the last neutron IS enough to cause it to fission.  Thus, conventional reactors burn not only U235, but also some of the Pu239 that is produced in this way.  Unfortunately, they don’t produce enough extra plutonium to keep the reactor going, so only a few percent of the U238 is “burnt” in addition to the U235 before the fuel has to be replaced and the old fuel either reprocessed or stored as radioactive waste.  Even though a lot of energy is locked up in the remaining U238, it is usually just discarded or used in such applications as the production of heavy armor or armor piercing munitions.  In other words, the process is something like throwing a log on your fireplace, then fishing it out and throwing it away when only a small fraction of it has been burnt.

    Can anything be done about it?  It turns out that it can.  The key is neutrons.  They not only cause the U235 and Pu239 to fission, but also produce Pu239 via absorption in U238.  What if there were more of them around?  If there were enough, then enough new Pu239 could be produced to replace the U235 and old Pu239 lost to fission, and a much greater fraction of the U238 could be converted into useful energy.  A much bigger piece of the “log” could be burnt.

    As a matter of fact, what I’ve described has actually been done, in so-called breeder reactors.  To answer the question “How?” it’s necessary to understand where all those neutrons come from to begin with.  In fact, they come from the fission process itself.  When an atom of uranium or plutonium fissions, it releases an average of something between 2 and 3 neutrons in the process.  These, in turn, can cause other fissions, keeping the nuclear chain reaction going.  The chances that they actually will cause another fission depends, among other things, on how fast they are going.  In general, the slower the neutron, the greater the probability that it will cause another fission.  For that reason, the neutrons in nuclear reactors are usually “moderated” to slower speeds by allowing them to collide with lighter elements, such as hydrogen.  Think of billiard balls.  If one of them hits another straight on, it will stop, transferring its energy to the second ball.  Much the same thing happens in neutron “moderation.”

    However, more neutrons will be produced in each fission if the neutrons aren’t heavily moderated, but remain “fast.”  In fact, enough can be produced, not only to keep the chain reaction going, but to convert more U238 into useful fuel via neutron absorption than is consumed.  That is the principle of the so-called fast breeder reactor.  Another way to do the same thing is to replace the U238 with the more plentiful naturally occurring element thorium 232.  When it absorbs a neutron, it eventually decays into U233, which, like U235, is fissile.  There are actually many potential advantages to this thorium breeding cycle, such as potentially greater resistance to nuclear weapons proliferation, the ability to run the process at slower average neutron speeds, allowing smaller reactor size and easier control, less production of dangerous, long-lived transuranic actinides, such as plutonium and americium, etc.  In fact, if enough neutrons are flying around, they will fission and eliminate these actinides.  It turns out that’s very important, because they’re the nastiest components of nuclear waste.  If they could be recycled and burned, the amount of residual radiation from the waste produced by operating a nuclear plant for 30 or 40 years could be reduced to a level below that of the original uranium or thorium ore in a matter of only a few hundred years, rather than the many thousands that would otherwise be necessary.

    So breeders can use almost all the potential energy in uranium or thorium instead of just a small fraction, while at the same time minimizing problems with radioactive waste.  What’s not to like?  Why aren’t we doing this?  The answer is profit.  As things now stand, power from breeder reactors of the type I’ve just described would be significantly more expensive than that from conventional reactors like EPR.  EPR’s would use enriched natural uranium, which is still relatively cheap and plentiful.  They would require no expensive reprocessing step.  Ask an industry spokesman, and they will generally assure you (and quite possibly believe themselves, because self-interest has always had a strong delusional effect) that we will never run out of natural uranium, that the radioactive danger from conventional reactor waste has been grossly exaggerated, and there is no long-term proliferation danger from simply discarding plutonium-laced waste somewhere and letting it decay for several thousand years.  I’m not so sure.

    Now, I have no problem with profit, and I find Hollywood’s obsession with the evils of large corporations tiresome, but I really do think this is one area in which government might actually do something useful.  It might involve some mix of increased investment in research and development of advanced reactor technology, including the building of small demonstration reactors, continued robust support for the nuclear Navy, and eliminating subsidies on new conventional reactors.  Somehow, we managed to build scores of research reactors back in the 50’s, 60’s and 70’s.  It would be nice if we could continue building a few more now and then, not only for research into breeder technology, but as test beds for new corrosion and radiation resistant materials and fuels, exploration of high temperature gas-cooled reactors that could not only produce electricity but facilitate the production of hydrogen from water and synthetic natural gas from carbon dioxide and coal, both processes that are potentially much more efficient at high temperatures, and even fusion-fission hybrids if we can ever get fusion to work.

    We aren’t going to run out of energy any time soon, but there are now over 7 billion people on the planet.  Eventually we will run out of fossil fuels, and depending entirely on wind, solar and other renewables to take up the slack seems a little risky to me.  Wasting potential fuel for the reactors of the future doesn’t seem like such a good idea either.  Under the circumstances, keeping breeder technology on the table as a viable alternative doesn’t seem like a bad idea.

  • Nuclear Energy and the “Too Cheap to Meter” Lie

    Posted on February 4th, 2013 Helian No comments

    According to a German proverb, “Lügen haben kurze Beine” – Lies have short legs.  That’s not always true.  Some lies have very long ones.  One of the most notorious is the assertion, long a staple of anti-nuclear propaganda, that the nuclear industry ever claimed that nuclear power would be “Too cheap to meter.”  In fact, according to the New York Times, the phrase did occur in a speech delivered to the National Association of Science Writers by Lewis L. Strauss, then Chairman of the Atomic Energy Commission, in September 1954.  Here is the quote, as reported in the NYT on September 17, 1954:

    “Our children will enjoy in their homes electrical energy too cheap to meter,” he declared.   …    “It is not too much to expect that our children will know of great periodic regional famines in the world only as matters of history, will travel effortlessly over the seas and under them and through the air with a minimum of danger and at great speeds, and will experience a lifespan far longer than ours, as disease yields and man comes to understand what causes him to age.”

    Note that nowhere in the quote is there any direct reference to nuclear power, or for that matter, to fusion power, although the anti-nuclear Luddites have often attributed it to proponents of that technology as well.  According to Wikipedia, Strauss was “really” referring to the latter, but I know of no evidence to that effect.  In any case, Strauss had no academic or professional background that would qualify him as an expert in nuclear energy.  He was addressing the science writers as a government official, and hardly as a “spokesman” for the nuclear industry.  The sort of utopian hyperbole reflected in the above quote is just what one would expect in a talk delivered to such an audience in the era of scientific and technological hubris that followed World War II.  There is an excellent and detailed deconstruction of the infamous “Too cheap to meter” lie on the website of the Canadian Nuclear Society.  Some lies, however, are just too good to ignore, and anti-nuclear zealots continue to use this one on a regular basis, as, for example, here, here and here.  The last link points to a paper by long-time anti-nukers Arjun Makhijani and Scott Saleska.  They obviously knew very well the provenance of the quote and the context in which it was given.  For example, quoting from the paper:

    In 1954, Lewis Strauss, Chairman of the U.S. Atomic Energy Commission, proclaimed that the development of nuclear energy would herald a new age. “It is not too much to expect that our children will enjoy in their homes electrical energy too cheap to meter,” he declared to a science writers’ convention.  The speech gave the nuclear power industry a memorable phrase to be identified with, but also it saddled it with a promise that was essentially impossible to fulfill.

    In other words, it didn’t matter that they knew very well that Strauss had no intention of “giving the nuclear power industry a memorable phrase to be identified with.”  They used the quote in spite of the fact that they knew that claim was a lie.  I all fairness, it can be safely assumed that most of those who pass along the “too cheap to meter” lie are not similarly culpable.  They are merely ignorant.