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CERN Physicist Warns About Uranium Shortage
eldavojohn writes "Uranium mines provide us with 40,000 tons of uranium each year. Sounds like that ought to be enough for anyone, but it comes up about 25,000 tons short of what we consume yearly in our nuclear power plants. The difference is made up by stockpiles, reprocessed fuel and re-enriched uranium — which should be completely used up by 2013. And the problem with just opening more uranium mines is that nobody really knows where to go for the next big uranium lode. Dr. Michael Dittmar has been warning us for some time about the coming shortage (PDF) and has recently uploaded a four-part comprehensive report on the future of nuclear energy and how socioeconomic change is exacerbating the effect this coming shortage will have on our power consumption. Although not quite on par with zombie apocalypse, Dr. Dittmar's final conclusions paint a dire picture, stating that options like large-scale commercial fission breeder reactors are not an option by 2013 and 'no matter how far into the future we may look, nuclear fusion as an energy source is even less probable than large-scale breeder reactors, for the accumulated knowledge on this subject is already sufficient to say that commercial fusion power will never become a reality.'"
The problem is that plutonium is a man-made material. We make it from uranium by bombarding it with high energy particles. So if you run out of uranium, you also run out of plutonium. This is of course dependant on us not discovering alchemy in the next 10 years. To be honest, that would be pretty awesome, if watching TV has taught me anything.
A lot of natural resources go into Solar panels. Resources that need to be mined.
For those who didn't read (the rather dense) TFA, a big part of his objection is that we don't have a good, safe technology for breeder reactors, and that our existing reactor designs require Uranium which is something of a limited resource. I've seen estimates that we have maybe 70 years of the stuff around if we went totally nuclear, but those could be high or low -- who knows (and the cost will be astronomical when we start to run short of it). Breeder reactors can extend the fuel lifetime for thousands of years. Unfortunately, the existing breeder reactors that we do have tend to be very unsafe and expensive, using things like liquid sodium (catches fire when it contacts air) for coolant.
This brings me to my main point: the current state of nuclear reactor technology is not sustainable. Most Slashdot nuclear advocacy goes like this: (a) start building reactors now, (b) don't worry about fuel supplies, we'll just build breeder reactors. The problem is that the reactors we build in step (a) may be entirely incompatible with the breeder reactors, and we may not be able to build enough of the breeders in (b) safely to move to this technology in the near term.
Both of these problems can probably be solved with technological developments, which means spending a lot of money on nuclear research. It does not necessarily mean "go out and build reactors", "give subsidies to the nuclear industry", which seems to be the preferred policy action of many nuclear advocates. I think this needs to be understood.
And you can't use them to make nuclear weapons.
That last part is why. :'|
And also ridiculously misinformed. From wikipedia:
The thorium fuel cycle creates mainly Uranium-233 which can be used for making nuclear weapons, and since there are no neutrons from spontaneous fission of U-233, U-233 can be used easily in a gun-type nuclear bomb. Thorium can and has been used to power nuclear energy plants using both the modified traditional Generation III reactor design and prototype Generation IV reactor designs.
Citation here.
My work here is dung.
Just to silence the "citation please" trolls who can't use google:
Energy from Thorium
Nuclear Green
Disclaimer: the second link goes to my uncle's blog. My grandfather worked on the original liquid fluoride thorium reactor at ORNL, and my uncle has advocated the technology for quite some time.
We're not running out of uranium. We are running out of *enriched* uranium. Fast breeder reactors (FBRs) solve the problem because they (a) run on plutonium and (b) transmute depleted uranium and other "waste" products from legacy reactors into useful fuel.
FBRs can can reprocess or dispose of weapons material and spent fuel from legacy nuke plants. Once bootstrapped with plutonium, they'll happily run on crap that your typical nuke plant considers useless waste. They're also more efficient. Would you rather have 100 tons of waste annually from a thermal reactor plant, or 2 tons from a breeder reactor? It's radiocative either way.
Expecting anyone to bring a commercial FBR online before 2013 is ludicrous. You'd be hard pressed to complete even a boring coal fired plant in that short of a timeframe. FBRs are also "scary" and utterly taboo for anyone besides trusted friends to own or operate, because the fuel that they produce happens to be plutonium that's great for making bombs. So, ummm, as with any nuke plant, you maintain a certain level of security. It ought to be common sense.
References:
http://en.wikipedia.org/wiki/Fast_breeder_reactor
http://en.wikipedia.org/wiki/Generation_IV_reactor#Fast_reactors
Here:
Existing CANDU plants can already use Thorium.
The infrastructure already exists for those bright enough to use an awesome design like CANDU.
http://www.nuclearfaq.ca/brat_fuel.htm
-- "Government is the great fiction through which everybody endeavors to live at the expense of everybody else."
The problem is that plutonium is a man-made material. We make it from uranium by bombarding it with high energy particles. So if you run out of uranium, you also run out of plutonium. This is of course dependant on us not discovering alchemy in the next 10 years. To be honest, that would be pretty awesome, if watching TV has taught me anything.
You're right, but also wrong. Plutonium is made from U238 (emphasis on 238). The nuclear fuel that we're using right now is U235. There is one hundred and fifty times more U238 in the ground than U235. So, by switching to plutonium, we expand the available supply of uranium by a factor of 150.
The whole debate about uranium fuel reserves is totally ludicrous. An utterly simple back of the envelope calculation demonstrates that the Earth contains sufficient uranium to supply fission power for billions of years. Uranium fuel will last literally longer than solar power (since the sun's remaining lifetime is only 5 billion years). Yet periodically we see attention whores showing up in Slashdot articles and crying that we will run out of uranium, a statement which is so obviously wrong that it is hard to explain by incompetence and bordering on the realm of malice.
Our global temperature is affected by three factors:
1. Amount of energy input.
2. Amount of energy stored or released.
3. Amount of energy radiated.
The amount of energy entering the Earth's atmosphere is, for all intents and purposes, a constant. The Sun is almost completely responsible for all of that.
If I have a black roof on my house, my roof will absorb the sunlight shining on it and turn it into heat. If I interrupt that with a solar collector, ~90% of it will still become heat, and ~10% of it will become electricity. As I use the electricity to do stuff, it generates heat. Including the losses over the wires, etc.
Net result: There isn't a significant difference in the actual amount of heat, only how we use the potential energy in sunlight before it turns into heat. Entropy is like that.
As far as the other two factors, we stored a crapload of solar energy and sequestered a crapload of carbon dioxide a long time ago in the form of dead plants and critters. That matter decayed and turned into what we now call "coal" and "oil". Burning those releases both that energy and CO2. CO2 is an insulator and therefore reduces heat radiation.
So if you use solar (or one if its indirect factors, like biofuel or wind) you get three wins - you're using heat that would be there anyway, you're not adding more heat, and you're not releasing sequestered material that may help the earth retain heat.
You do, however, get one loss. We've already built a HUGE infrastructure for using sequestered energy and built our demand around it. Direct and indirect solar has a long way to go before it can replace all of our wants, if it ever can. At some point, mankind is going to have to face "want" versus "need".
"This post contains words, known to the State of California to cause thought. Wash brain thoroughly after reading."
If you read the *entire* Wikipedia article on the Thorium fuel cycle, you would understand why Thorium is proliferation resistant instead of calling the parent "ridiculously misinformed".
http://en.wikipedia.org/wiki/Thorium_fuel_cycle
"Because the 233U produced in thorium fuels is inevitably contaminated with 232U, thorium-based used nuclear fuel possesses inherent proliferation resistance. Uranium-232 can not be chemically separated from 233U and has several decay products which emit high energy gamma radiation. These high energy photons are a radiological hazard that necessitate the use of remote handling of separated uranium and aid in the passive detection of such materials."
http://en.wikipedia.org/wiki/Molten_salt_reactor
"It is verifiable because the epithermal thorium breeder produces only at most 9% more fuel than it burns in each year. Building bombs quickly will take power plants out of operation."
Basically, because almost all naturally occurring Thorium is 232Th, it's possible to isolate Thorium fuel chemically -- without centrifugation. In other words, a country that uses Thorium exclusively for fuel has no reason to develop centrifugation technology. On the other hand, separating 233U from 232U requires centrifugation. Thus, aforementioned countries would be unable to access the 233U they produce for bomb-building purposes.
Also, the poor breeder coefficient of 233U Thorium reactors means that most of the 233U produced by the reactor is required to produce the neutrons that convert fertile Thorium into more 233U. If you were to remove the 233U from the reactor for use in a bomb, you would halt additional production of 233U by the reactor. Either you would have to harvest very little 233U over a long period of time, or you would have to supplement the Thorium fuel with some other fissile material such as bomb-grade plutonium (and if you already had access to that, you wouldn't be trying to produce bomb-grade material in the first place).
While it's possible to produce a bomb using a the thorium fuel cycle, it is inefficient and requires advanced centrifugation technology to mitigate the 232U. It would be easier to just start with uranium ore.
Fast breeder reactors (FBRs) solve the problem because they ... (b) transmute depleted uranium and other "waste" products from legacy reactors into useful fuel.
FBRs can can reprocess or dispose of weapons material and spent fuel from legacy nuke plants. Once bootstrapped with plutonium, they'll happily run on crap that your typical nuke plant considers useless waste.
Um, no. Breeder reactors can produce fuel for other reactors by irradiating natural uranium with neutrons, which produces primarily plutonium-239 with several other minor byproducts. They cannot by themselves reprocess spent fuel ("waste") into usable fuel, although they can play a (minor) part of this process.
There are several steps that spent fuel must pass before it can be used as fresh fuel in a common LWR again. To begin with, the spent fuel contains a lot of nuclear poisons that prevent the reactor from retaining the nuclear chain reaction, so these must first be removed from the spent fuel. This is not done in a breeder reactor, but rather using centrifuges similar to the ordinary enrichment process. This produces two products: Real waste, and a precursor to fresh fuel. The waste can be transmuted into less dangerous waste in a breeder reactor or an accelerator-driven reactor. The fuel precursor then needs to have elements such as plutonium removed (unless it is meant to be part of Mox fuel) before it can be recast into its ceramic form and used again in an ordinary LWR.
As noted above, a breeder can be used to transmute the real waste into less dangerous waste, but its primary function is to transmute natural and depleted uranium into usable isotopes through neutron capture in that uranium. Breeders are not reprocessing facilities.