(2) Wed Nov 18 2009 19:28:
In the scant months I've subscribed to it, the arXiv blog has served up many interesting and possibly insane bits of scientific speculation. The longest paper it's caused me to read is Michael Dittmar's four-part "The Future of Nuclear Energy", the most recent part of which was published recently.
On the surface the paper is an overview of the state of nuclear power, but an interesting argument quickly forms that the world doesn't have much exploitable uranium left. Here's my summary of the main argument, with extraneous and historical information removed:
- Every estimate of how much uranium is available uses data from the IAEA "Red Book".
- The Red Book is not a scientific document. The data is self-reported by uranium-mining countries, and is given to an unrealistic degree of precision with no margin of error. There's no way to check it.
- Trends in the Red Book year-over-year indicate that certain countries are fudging their data, for instance by pumping up the huge "uranium reserves that probably exist" number. This number being the main underpinning of the claims that there's enough uranium to supply our cravings for nuclear-derived electricity for however many years.
- Even if the Red Book is accurate, "however many years" is not as long as it sounds, since nuclear power plants are built to amortize their cost over 40-60 years. And right now nuclear power only generates 15% of the world's electricity. If you want to double that, "however many years" gets cut in half, and you still haven't replaced fossil fuels.
- What about high tech like breeder reactors? According to Dittmar, there are only a couple commercial breeder reactors in operation and they don't really produce a net increase in radioactive material. It's more like regenerative braking in an electric car, where you get some of the energy back.
The technical problems with breeder reactors can theoretically be overcome with more research. (Dittmar has no hope for commercial fusion.) But, given the long development lead times and the fact that the necessary research isn't being funded right now, by the time they're commercially viable there won't be any tritium to run them on, because of the uranium problem. (Tritium can be generated in a conventional uranium-burning nuclear reactor, but very slowly--and it has a half-life of 12 years.)
I was intrigued by this analysis, because I always think a claim that some data set is wrong or has been misinterpreted is interesting. But because it's such a seductive narrative I also wanted to look at a high-quality response to Dittmar's claims. Any problems with the logic aside, there are a couple problems with Dittmar's presentation that give bad smells:
- Dittmar has an obvious bias against nuclear weapons, a bias that seems quite sensible to a civilian but which you should probably not write into your papers if you're trying to convince other nuclear scientists of something. Seriously, don't tell your readers to watch Dr. Strangelove. Anyone interested enough to read your paper has already seen it.
- Dittmar also believes that certain recovery techniques like reprocessing fuel rods for plutonium will inevitably drive proliferation of nuclear weapons. I've heard this argument before but I don't understand the physics of it, so I can't judge. Anyway, this really has nothing to do with his main argument, except insofar as he's attacking a pie-in-the-sky idea where the whole world uses nuclear energy for exclusively peaceful purposes.
- I don't think English is Dittmar's first language, because his grammar is not great. This is nothing that couldn't be fixed by an editor, but it makes his writing look crackpot-ish.
So I was on the market, and happy this morning when I saw that Paul Raven posted about Dittmar's paper on Futurismic today, and linked to this 2008 post on the Wall Street Journal environmental weblog. That weblog post dismisses contemporaneous "peak uranium" concerns by... citing the IAEA Red Book data. But the main point of Dittmar's paper is that the Red Book data is unreliable!
In desperation, I turned to the comment section on the original arXiv blog posting, hoping that there would at least be people arguing over the paper instead of just quoting the Red Book. Well, there was a lot of irrelevant arguing (fair enough, since there's a lot of irrelevant points in Dittmar's paper), but below is a rough classification of the relevant rebuttals:
- "Dittmar is an obnoxious jerk." This appears to be true, and it might also be relevant. "The data set you've been implicitly trusting for years doesn't look right" is the kind of argument that could give you a reputation as an obnoxious jerk, but it's also the kind of thing an obnoxious jerk would say just to make trouble.
- "Critiquing the Red Book data doesn't prove anything." Given that everyone who argues against peak uranium references a document that has its ultimate source in the Red Book data, it seems legitimate to critique that data. BUT, a critique only establishes that we don't know something. You can't build a positive argument on this.
- "There's lots of uranium we just haven't looked for yet." But any attempt at quantifying this means relying on Red Book data, which Dittmars claims makes things look too good. Also, getting the uranium into a reactor is a complicated process with a long lead time, which starts with looking for the damn uranium.
- "We won't run out of uranium, it'll just get more expensive." Sure, but any attempt at quantifying this means bringing in Red Book data. Part III of Dittmar's paper claims that the Red Book gives an incoherent estimate of the total cost of the world's uranium reserves. BUT, that just means the Red Book is wrong about the price classification. It doesn't make the incoherently-priced uranium nonexistent or infinitely expensive.
- "We don't have to get fissile material from the ground." Indeed, there are a lot of interesting things we could do to get more fissile material: decommissioning nuclear weapons, reprocessing uranium or fuel rods. But these things are accounted for in the Red Book and covered in Dittmar's paper. We're already doing all of those things to some extent, and the only one that gives significant material is decommissioned nukes (currently providing 25% of world uranium). We can ramp up these processes, but there's a long lead time.
OK, so after colliding thesis and antithesis in my Hegelian particle accelerator, I've come to the following tenative conclusions:
- The Red Book data is unreliable. It's based on self-reported data by interested parties. There's fudging and uranium reserves are priced in an incoherent way. For political reasons, the Red Book itself can't mention this fact. The same problem probably exists with, eg. reported estimates of coal reserves, but it's worse with uranium because 1) there's more geopolitical incentive to fudge, 2) the numbers are smaller because uranium is much scarcer than coal.
- This doesn't change the basic rules of natural resources. If uranium gets scarcer the price will go up and people will try to extract marginally recoverable uranium. This would be true even if the Red Book with its incoherent pricing didn't exist. We just don't have an accurate estimate of the prices.
- If the Red Book data is bad, you can't use it. As Daniel Davies says, "If you have doubts about the integrity of a forecaster, you can't use their forecasts at all. Not even as a 'starting point'." By showing that the Red Book data is bad, you can drive demand for a better set of numbers. If you can prove that the numbers are systematically manipulated, you might be able to cancel the systematic error out, though you'll never know for sure. But you can't demonstrate that the numbers don't look right and then make recommendations based on what you think they really are.
- Breeder reactors are not as cool as I'd thought, and progress on them slower than I thought. This is where the "obnoxious jerk" factor comes in. It sounds like Dittmar has had the following conversation with other physicists:
"Even if you solve problem K, how are you going to solve X, Y, and Z to make your reactor capable of 90% uptime in a commercial setting?"
"Why do I have to solve X, Y, and Z? It's hard enough getting funding for K. Let someone else do it. You jerk."
The problem according to Dittmar is that these problems will get solved serially over the course of 30 years and then we'll spend 15 years building a power plant and by that time the tritium will have decayed. The timing here depends on the question of how much uranium there really is, but the general argument is that with more funding and more physicists we could solve X, Y, and Z in parallel with K.
- The big problem with any fissile-material-related "we'll be fine because of X" argument is lead time. It takes longer to get from uranium-in-the-ground to uranium-in-a-reactor than it takes to get from coal-in-the-ground to coal-in-a-furnace. It takes a long time to ramp up uranium reprocessing or any other exotic solution. It takes a long time to build a nuclear power plant or to get an experimental result to commercial viability.
So there's something here, but it doesn't seem like a bombshell. Basically, the Red Book numbers are inaccurate and vague in many different ways, but used in policy arguments as though they were very accurate, because they're the only game in town. It's possible the numbers are so far off the mark that there will be a uranium price shock in 2013, but it seems pretty unlikely.
I'm interested in hearing the opinions of those who know more about these topics.
- Comments:
My impression was the concerns about "peak uranium" were not very credible. Here is a random probably-biased webpage laying out the argument: http://www.world-nuclear.org/info/inf75.htmlI don't know how to find trustable authorities on this topic, but the basic argument seems way more plausible than most shill rhetoric. The important difference between uranium and fossil fuels is that uranium is *ridiculously* energy dense. You can power a city with a few tons, or whatever. That means that sure, extracting uranium from poor ores like, say... seawater... is certainly not economically viable right now -- but that's not the interesting question. The interesting question is whether you can get net positive energy output, and AFAICT the answer is yes.Combined with that is that -- I'm told -- everyone stopped prospecting for new uranium when the cold war ended and old nukes flooded the market; it's not like oil, where we've searched *very very hard* and still aren't finding any new deposits.Like I said, though, I have no idea how to figure out which sources are actually real; just, the arguments above seem to me to make more scientific sense than anything I've heard coming from, say, the "wind and solar and magic energy distribution and storage systems will cover baseline load!" people.
So raw unprocessed uranium is far less abundant that oil and it will be depleted sooner. And at present, most of the raw unprocessed uranium is processed and converted into nuclear fuel that is mostly used in power generation and some into weapons. At some point, the nations holding these weapons will have to determine if they want to keep the weapons for protection or reuse the fuel for power generation. This seems like a possible future where there will be no nuclear weapons by shear necessity for power or other non-military uses.
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