First of all, you have pointed to one liquid metal
breeder reactor as evidence that "nuclear recycling doesn't work." Mox fuel works quite well in thermal reactors. It is not economic to use it right now simply because uranium is so cheap. Uranium will not remain cheap forever, as everybody who understands nuclear energy knows, and even some who do not understand nuclear energy know. On the other hand, everybody knows that nuclear fuel will never really be "expensive." It is easy to show that at $200/kg, more than 5 times its current price, the price of nuclear fuel is still less than the equivalent of gasoline at a few mils (fractions of a cent) a gallon.
http://www.eppo.go.th/ref/UNIT-OIL.htmlWe see here that 1 ton of oil equivalent = 41 billion joules of energy has, at 25C, roughly 7 barrels of oil. At current prices this is approximately 350 USD
before refining. Given that a fission reaction normally gives about 200 MeV = 200 X 1.609 X 10^(-19) J/eV) = 3.2 X 10^(-11) J, we see that "only" 1.3 X 10^21 atoms are required to give off as much energy as a ton of oil. Dividing this number by Avogadro's number 6.02E23 we see that 0.002 moles of fissioned uranium are required to equal 1 metric ton of oil. If we are using a CANDU reactor, which runs off natural uranium, atomic weight, 238, this corresponds to half a gram of uranium. At $200/kg, 5 times the current price, this is the equivalent to a ton of oil costing ten cents. Since a ton of oil has about 484 gallons, the "per gallon price" for uranium is 0.02
cents (not dollars) per gallon.
Easy to show, as promised.
If I'm wrong, prove it, and not with some dumb internet link itself linking to an equally dumb article written by a pathetic reporter somewhere. Calculate it for yourself, just as I have done. Show me where my numbers are wrong.
I don't know where you people get your numbers, from illiterate reporters I guess, but if you can tell me how this makes nuclear fuel "uneconomic," I'm just dying to hear about it.
No, we are ALL dying to hear it. Our atmosphere is being destroyed in service to this nonsense.
However, it is true that if the price does someday reach $200/kg for uranium, the value of spent nuclear fuel - now essentially worthless because virgin fuel is so cheap - will become increasingly important. This will happen only of course, if the majority of us or even all of us are not killed by global climate change. The only existant mechanism where the majority of us can avoid being killed by global climate change is to embrace nuclear power as quickly as is possible.
There is nothing "deceptive" about the argument for nuclear recycling. It already exists although "once through" uranium itself is seldom used, because such use would require certain physics changes. That doesn't mean it's "garbage" or waste. It only means that it is a resource not currently required. This may come as a surprise to anti-environmentalists, but not every resource needs to be gobbled up immediately or else thrown away.
The facts about radioactivity decreasing after 1000 years of such recycling is, as noted in my original post in this thread, regularly reported in the scientific literature. The people who write about such things are scientists and engineers. There are entire texts, long ones too, that are devoted to the subject of the nuclear fuel cycle. If you can find a reputable engineering text that says the nuclear fuel cycle doesn't work, post it here. Here is a text, that I've been scouring for a few years now that says the nuclear fuel recycling scheme is an excellent idea: "Nuclear Reactor Physics" by Weston Stacey, copyright 2001, John Wiley and Sons, publishers. Pages 195-240 cover the fuel cycle quite well, and there is none of this selective "tell me what I want to hear" jerk off stuff. It's all physics.
One can always find some article in some newspaper somewhere that points to some specific instance of a nuclear problem and attempts to color the whole industry with that paintbrush. Moreover, people who make such weak - and, yes deceptive, arguments - do not apply the same criteria to their favorite alternative - which is usually expressed in some doublespeak statement like "We have more than enough uranium, but it won't be economically competitive to other sources like wind or solar." This is nonsense.
I wish we would apply this particular gem of selective thinking "You cannot responsibly make an argument based on theoretical assumptions that have failed to produce..." and apply it to solar energy. There is not 1 gigawatt of solar energy (PV) installed anywhere on the planet. There are over 360 gigawatts of nuclear capacity installed and more than 50 more or so, under construction.
If solar and wind were in fact cheaper, they would be being installed at the same rate as nuclear energy. It's not even close. It will take decades and decades, longer than my remaining lifetime to have 50 gigawatts of PEAK solar capacity under construction and even then, it will work only under exactly the right conditions, one of the wrong conditions (for PV) being night time, which still, last I looked, occurs at least once every 24 hours.
What is deceptive is the failure to consistently apply the same criteria to solar, fossil, geothermal, whatever as one applies to nuclear. This is not done, and if there is anything "deceptive" this would be it.
Do you really want to get into a discussion of whether solar or wind facilities have ever been shut down for economic reasons?
Short lived nuclei have higher specific activities
by definition . They are very radioactive, but they disappear almost before they can be noticed.
When a U-235 nucleus is split yielding, for instance, two neutrons, a atom of tellurium-133 (this nucleon results in 3.66% of fissions with thermal neutrons) and an atom of zirconium-100 (which results in 5.78% of fissions with thermal neutrons) two new radioactive decay chains are established. However, these isotopes have, respectively, half-lives that are 7.1 seconds and 12.5 minutes. They are extremely radioactive, but both are essentially gone within a few hours of reactor shutdown. The radioactive daughter nuclei that are radioactive, isotopes of niobium and technetium in the case of zirconium-100, and iodine and xenon in the case of tellurium are also very short lived. The product nuclei, of both decay chains, Molydenum-100 and cesium-133 are stable nuclei and decay no further.
(Actually Molydenum-100, a naturally occurring isotope, has recently been discovered – as predicted by the nuclear stability rules and the existence of the stable nuclide ruthenium-100 to be very, very, very slightly radioactive. Mo-100 has been shown to have a half-life of roughly 1 X 10^19 years, meaning that in 100 grams of the pure isotope there are roughly 4 decays every
hour – how scary. Mo-100 formed in the first 100 years of the universe – if any was in fact formed back then – would still exist today, essentially unchanged.)
Of all of the above mentioned nuclei, the one with the longest radioactive half life is xenon-133, which has a half-life of 5.243 days. Essentially then, all of the radioactivity associated with this particular fission reaction is gone with a few weeks. In fact almost none of the nuclei created in this particular set of reactions over the fuel life time are ever likely to find their way out the reactor. Almost all of the decays take place while still in the reactor where they generate heat that drives the turbines. When the products of this particular fission reaction n(U-235)Zr-100,Te-133 are removed from the reactor, they will be stable nuclei, not measurably radioactive at all.
One of the things that radioactive paranoid fear mongers try to evoke when pretending that nuclear power is more dangerous than its alternatives is that so called “nuclear wastes” “lasts for millions of years.” This, like most of the illiterate claptrap they spew, is very misleading. The nuclei that last longest are precisely those that are the least radioactive and therefore the least “dangerous”- to the extent that any danger at all actually exists. (I repeat, no one yet has actually died from the storage of “dangerous” so called “nuclear waste.”) Moreover, in each case where an actinide has been destroyed by fission, a radioactive nucleus with many potential radioactive daughters – all of which will eventually decay in the environment – is eliminated.
By the way, although I hear again and again from people with a very poor understanding of chemistry and physics, it is not true that dilution is the solution to pollution. The fact that uranium is not concentrated in the billions of tons of rock and soils in which it is contained does NOT make it innocuous. As it happens, I live in New Jersey, right on the Reading Pronge, a rather large formation of uranium bearing rocks. I have measurable radon in my basement. I am required by law to ameliorate this situation. The reason: Naturally occuring uranium is one of the major causes of lung cancer in the world; aside from smoking, in fact, it is the largest. The concentration in my basement, which is at the action level, is about 1 picocurie per liter. This is very dilute, but it is still technically not "harmless."
For the insistence on the twisted and distorted logic of what I call "nuclear exceptionalism" - wherein issues that should apply to the evaluation of all energy sources are applied only to nuclear case, and then with vast distortion - anti-nuclear anti-environmentalists toy with global climate change and spout all sorts of drivel about solar capacity that has been promised for decades but still doesn't exist and probably never will exist in sufficient quantities. This is criminal. Global climate change certainly represents one of the greatest threats to humanity in my lifetime – and I lived through the Cuban missile crisis. Annihilation through either nuclear war or nuclear accidents is hardly as likely as global climate change. In fact global climate change, as it is now underway, is a certainty, and no longer a mere probability.
We don't have 40 years to wait for the Greenpeace partially solar nirvana. We need something that works now - something that is not dependent on the emissions greenhouse gases. There is really only one alternative.
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