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Archive for the ‘nuclear reprocessing’ Category

Barack Obama, nuclear energy and Yucca Mountain.

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Putting aside, for now, rhetoric like “OMG Obama will kill nuclear energy”, one of the only “anti-nuclear” positions that president-elect Obama has actually made overtly clear on the issue of nuclear energy is that he is opposed to the opening / licensing of the geological repository for radioactive waste disposal at Yucca Mountain.

However, it should be realized that “No Yucca Mountain facility” is not saying “No to nuclear energy”.

I really don’t think a Yucca Mountain style geological disposal facility is a prerequisite for the continuation or the expansion of nuclear energy in the United States for the foreseeable future.

Nuclear energy works just fine at present with no Yucca Mountain, and it will continue to work in future, even without Yucca Mountain going ahead.

If Obama’s position on Yucca Mountain causes the government, the nuclear energy industry, and the public to pause for a moment, step back, and ask if branding all that used fuel containing uranium, plutonium and other useful, valuable material as “waste” and sending it to geological disposal at Yucca Mountain is really a sensible proposal, then I really don’t think that’s a bad thing.

In fact, if Obama was to back efficient utilisation of these nuclear materials as the alternative to disposal at Yucca Mountain, then I wouldn’t expect to see a great deal of opposition to such a plan, from nuclear-literate parties, at all.

The used nuclear fuel removed from a conventional LEU-fueled light-water reactor is about 25 tonnes per gigawatt per year – the equivalent of less than two 15-tonne dry storage casks per reactor per year – something that is clearly not difficult to deal with.

If the uranium and plutonium comprising 97% of the nuclear fuel is recovered and re-used, and the remaining 3%* is put into dry storage casks, then just one storage cask provides enough capacity to store the material for one reactor for twenty years. Of course, of that 3% of fission product material, half the fission products aren’t even radioactive at all, or they have extremely short half-lives. Many fission products, both radioactive and not radioactive, are valuable, exotic and useful materials, with specialised, useful and interesting applications. The assumption that all such fission products would be treated as “waste” is, therefore, especially pessimistic.

* (You can account for the minor actinides (Np, Am, Cm, Cf) in either category. They constitute a very small amount of mass either way. Such actinides, like Pu and U, can be fissioned in a nuclear reactor as sources of energy, and like many fission products, they can also be used for specialised technological and scientific applications, such as the production of 238Pu from 237Np, and the use of Cf and Am:Be as neutron sources.)

Still, it seems a real shame to waste all that money that we’ve already spent on YM if it’s not going to be used. I’m not sure off the top of my head how far underground the tunnels at Yucca Mountain are, but perhaps it could be used as a deep underground laboratory, or something, just as the Waste Isolation Pilot Plant is?

Still, there are approximately 50,000 tonnes of used nuclear fuel already in the United States, the result of the last 50 years of nuclear energy. Opponents of nuclear energy are quick to point that out, but under a scenario similar to that elucidated above, with the separation of easily usable plutonium and uranium, the significantly radioactive fission product materials only constitute 1500 tonnes, or 100 DSCs worth. Until a geological repository is built, or those fission products are put to productive uses, that’s only one additional storage cask that need be stored at every power reactor in the country.

In the foreseeable future, with no Yucca Mountain, dealing with nuclear byproduct materials, storing them safely and securely on site, is not impractical, and it’s not intractable, and it’s not unsafe. There is nothing here which impedes or prevents a revival of nuclear energy generation.

Of course, under the Nuclear Waste Policy Act, the government will have to compensate nuclear utilities for the costs of this storage. No, this does not mean handing out government money to nuclear utilities – it means giving the Nuclear Waste Fund money that is supposed to go to Yucca Mountain back to the nuclear utilities in order to pay for the management of the existing 50,000 tonnes (approx.) of used fuel (and/or processing thereof), and more importantly, it ought to mean not requiring nuclear utilities to pay any more money – more correctly, not requiring nuclear electricity customers to pay any more money – for the Nuclear Waste Fund, until we know that a geological repository for radioactive waste is going ahead. Otherwise, what exactly are they paying for?