“The Oil Drum” Hasn’t a Clue What They Are Talking About
April 21st, 2008
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A website called “The Oil Drum” seems to be getting a lot more traffic than it deserves, discussing energy oil and the economics related to the two. One of the things that they seem to have a big problem understanding are issues related to nuclear energy. The new term out there is “uranium peak.” Now lets first remember that we still have not hit the “oil peak” and it could be decades away by some estimates – the increase in price is all about demand and not supply. Also “peak” does not mean that we “run out of” something but rather that the tipping point has been reached and the availability finally begins to be reduced, although certainly not overnight.
The “Uranium Peak” thing has come up on the site again and again and again. However, simply saying something enough actually, believe it or not, does not make it true. The first thing one needs to consider is that the energy density of uranium is ridiculous – almost incomprehensible in terms of chemical energy, and it’s not really a “rare” mineral either.
At the moment, there is enough spent nuclear fuel to power the world’s energy needs for some time through reprocessing alone. Of course, this does not consider a true breeder-based fuel cycle. In that case, the fuel we just have on hand and the depleted uranium left from years of enrichment could provide the energy needs of humanity for more than a century. Then there’s thorium. Thorium can also be used as a nuclear fuel through breeding into uranium-233. This is not theoretical – it can be done and has been done. The molten salt reactor is one elegant way of using thorium with high effeciency and little waste. However, it can also be used in existing reactors. CANDU reactors, for example, have already been shown to work just fine on the thorium cycle. Thorium happens to be about three times as common as uranium.
Right now, according to the IAEA, we have no worries of running out of conventionally recoverable uranium ore for the next few decades at least. Of course, if we ditch the current once-through fuel cycle you can multiply that by at least ten times and up to one hundred, in a high efficiency fast breeder system. France uses nuclear reprocessing and although they haven’t yet transitioned to next-generation reactors, they currently have enough fuel on hand to assure that even if all mining and importing stopped, they’d have no electrical shortages for years. Here in the United States we have even more spent fuel which can be harvested for years of energy. Adding in U-238 which we currently tend to sit on, despite being “fertile” material for breeding more fuel. In addition to this, the US alone happens to have up to a decade worth of thorium on hand, which the DOD stockpiled in the 1960’s. Realizing the potential for thorium, the DOD decided it would be a good idea to get a whole lot of it together incase it was needed. Despite not being dangerous, it was recently buried in Nevada (thankfully not too deeply) because nobody wanted the stuff.
Aside from the current stockpiles, it’s important to note that running out of “easily recoverable” uranium does not mean running out of uranium. Since nuclear energy is less dependent on the price of fuel for the final cost of energy, it can still be profitable even when lower grades of ore are used. This may never even be an issue, if our current reserves are used wisely, but the idea of uranium just plain “running out” is not ever going to be a reality – at least not in the next few million or even billion years.
It’s worth noting that uranium production is tied strongly to stratigic policy and not simply market forces. The United States only has about 3% of the uranium reserves of the world and the ore avaliable in the US is not of the highest concentration or ease of recovery. Today the US gets most of its uranium from Australia and Canada but at one time nearly all the uranium was mined domestically despite the deposits not being of the best quality. Why? Because during the cold war it was mandated and subsidized (though not that heavily) because domestic uranium was considered a critical stratigic issue. Today those mines are generally not used. They’re not depleted or anything, but it’s more economically favorable to import uranium.
For comparison:
One kilogram of uranium – slightly larger than a size D battery:
540 Metric Tons of Light Sweet Crude Oil:
Approximately the same amount of energy!
This entry was posted on Monday, April 21st, 2008 at 7:19 pm and is filed under Bad Science, Enviornment, Nuclear, Obfuscation, Politics. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.
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April 23rd, 2008 at 3:59 am
Michael Ejercito said:
Not sure I understand your question. The 300 $/KgU is for natural uranium. The 25 milligrams is for natural uranium. It takes 8.9 Kg natural uranium to make 1 Kg of enriched reactor fuel, of which only a couple percent is actually fissioned. So very approximately about 0.1 mg is actually fissioned to make a Kwh, but 25 milligrams must be mined for the once through fuel cycle.
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April 23rd, 2008 at 12:05 pm
Paul Studier said:
Burn up and required enrichment varies a lot by reactor. CANDUs usually run on natural uranium and can even run on “spent” LWR fuel and the ideal enrichment is around 0.9% U-235.
All reactors using uranium fuel breed some plutonium from U-238, part of which is also fissioned in the reactor. Reactors with good neutron economy like CANDU can achieve much higher burn-up than you might expect from looking at what fraction is fissionable U-235; but the burn-up without reprocessing is often limited by potential damage to fuel rods and fuel pellets. With better self-healing materials or different form factors for fuel such as molten salt or coated TRISCO particles embedded in graphite blocks or pebbles it is believed that you can safely increase the burn-up with a low risk of damaged fuel elements.
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April 23rd, 2008 at 5:09 pm
RefJeff1980 said:
This does smack of a “free energy” claim, and would have the same economic effect as perpetual motion, eg, the fuel cost for
the life of the device being an insignificant fraction of the total cost, if only we could actually *have* the damned things. Lightspeed
squared is 25 billion kilowatt-hours per kilogram, at current market rates 250 billion dollars per kg times the efficiency times the
fraction of mass actually converted. And the cost of a kilogram of U-235 is… what?
Come to think of it I remember reading of a “free energy” crackpot claiming that his was NOT a claim of perpetual motion
but that his gizmo got its energy by destoying a tiny fraction of the long copper coil of which it was constructed.
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April 23rd, 2008 at 5:22 pm
Burya Rubenstein said:
Not really. However the cost of fuel is a very small part of the cost of making power with nuclear fission. Currently it is so cheap that we can get away with burning only one or two percent of the available fissile material in the fuel and still beat the cost of mining and fabricating fresh fuel. This is why talk of running out and poor EIOR for nuclear energy is just so much hogwash. We haven’t even scratched the available energy of the uranium that’s above ground now.
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April 23rd, 2008 at 5:42 pm
Burya Rubenstein said:
It’s not. The mass of U235 is NOT completely converted to energy. Fission splits an U235 atom into fission products and neutrons. The sum of the masses of fission products and neutrons is almost the same as the mass of the original U235. But only almost. The “lost” mass is what was converted to energy. It’s just that that mass-loss during fission of 1 kg U235 is many orders of magnitude larger than the mass-loss during an equivalent amount of combusting chemical fuel.
And yes, if you extremely precisely weigh the amount of for example coal and O2 before combustion, and then also weigh the combustion products with the same precision, you would see a lower mass. This is the mass equivalent to the extracted energy using Einsteins famous equation. Sounds crazy, but it is part of normal modern physics. E=m*c^2 does not only apply to nuclear fission or fusion. It’s a universal law. But nuclear fission and fusion allow us to convert a much larger fraction of the original mass by many orders of magnitude compared to the chemical binding energies.
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April 23rd, 2008 at 7:52 pm
KLA said:
Yes, all the matter in fission is certainly not converted to energy not even in the case of fusion. I still think that nuclear energy can be said to be a matter-energy conversion more than you could say for chemical energy because there is actually part of the matter which is not accounted for except as energy. The products weigh less but also there is decay right away and later where you have positrons created which convert electrons to 100% energy – so particles are converted and then also you have beta decay at the time of fission and shortly after and on the sub-atomic level there is a smaller amount of mass to a proton than a neutron and it is not all accounted for by the electron and neutrino but the energy of the electron.
I think it’s more valid in nuclear energy to say it’s actually mass to energy where in chemical energy the components don’t have any mass but the bond does have slight mass. I don’t think this is completely analogous to binding energy.
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April 23rd, 2008 at 9:26 pm
Interesting. I could see it both ways. You almost never hear of mass/energy equivalent as applied to chemicals but it’s technically there as a state of the electrons. In nuclear energy you do definitely have mass to energy as well and there are I guess particles which are turned to energy but in on a quantum sub-atomic level at which energy and particles are not always distinct.
All energy has mass though. The particles are in a different state and the components might change related to that. The only real conversion of a classical particle would be if there were an anti-particle generated in the process of fission or the decay immediately following it. That sometimes happens but that is not where most of the energy comes from in fission.
Oh by the way: The graphic where there is 1kg of uranium to 530 metric tons of crude – I looked at your numbers and that’s accurate for nominal burnup in a fast reactor. If you had complete burnup of fissile or fertile material then the actual energy is going to be seven or eight times as much as illustrated.
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April 24th, 2008 at 2:07 pm
Coal contains trace amounts of uranium and thorium and after burning the percentage of uranium in the ash reaches levels where recovery is economical feasible.
“For the year 1982, assuming coal contains uranium and thorium concentrations of 1.3 ppm and 3.2 ppm, respectively, each typical plant released 5.2 tons of uranium (containing 74 pounds of uranium-235) and 12.8 tons of thorium that year. Total U.S. releases in 1982 (from 154 typical plants) amounted to 801 tons of uranium (containing 11,371 pounds of uranium-235) and 1971 tons of thorium. These figures account for only 74% of releases from combustion of coal from all sources. Releases in 1982 from worldwide combustion of 2800 million tons of coal totaled 3640 tons of uranium (containing 51,700 pounds of uranium-235) and 8960 tons of thorium.”
This is from a paper out of Oak Ridge.
http://www.ornl.gov/info/ornlreview/rev26-34/text/colmain.html
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April 24th, 2008 at 7:35 pm
D Palmer said:
Yes, uranium and thorium are not that hard to extract from something with other components, like coal ash. Uranium is probably easier than thorium but there would be more thorium and thorium of course makes a very good fuel. Both are totally doable though.
I just don’t know if I’d support recovery from coal ash unless it were really necessary to do so to augment a short supply. Considering the other things in coal ash, I really don’t know that it would be worth the risk that it might get discharged and the difficulty handling it with any enviornmental assurance.
I really think coal ash and the residue from coal burning in general is too nasty to mess around with. It would be better to collect it in super strong casks, then take it somewhere that it could be embedded into a chemically and physically inert vitrified material and then entombed at great depth in a geological stable area. We would just have to hope that future generations never happen to drill into it or accidentally dig it up because it would be a disaster. Maybe we could put some signs on top of where we put the vitrified coal waste in multiple languages so that hopefully we’d warn future generations
It would be nice if we could blast it into deep space but the prospect of a rocket failure would be catastrophic for the world!
That is how nasty coal waste is!
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April 25th, 2008 at 5:06 pm
Chem Geek Gregor said:
It took me a few lines to realize the sarcasm.
Very good post.
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July 2nd, 2008 at 6:03 am
Vjatcheslav said:
I thought that grid conductors (at least for overhead lines) were made of aluminium, with a small amount of yttrium added to improve conductivity.
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