Here's a beguiling headline and story that just ran in the UK:
- The Telegraph (Jan 6) Ambrose Evans-Pritchard: China blazes trail for 'clean' nuclear power from thorium / The Chinese are running away with thorium energy, sharpening a global race for the prize of clean, cheap, and safe nuclear power. Good luck to them. They may do us all a favour;
A constant since the dawn of the nuclear age has been speculation – backed by experiments – that there are other ways to harness the atom for electricity than with the standard uranium fission reactors that bring with them such headaches as waste disposal, security risks including possible conversion of their related hardware to weapons production, and the possibility of meltdowns such as those seen since at Chernobyl and Fukushima. Breeder reactors that would get more of the latent energy from the original uranium, fast neutron and high temperature units that could consume most of their high energy waste in their cores and leave less of an atomic garbage dump problem, and so on. Always on the list, if not at the top, has been a fuel cycle that looks great on paper, and relies on thorium-232. It is abundant, can't go into runaway chain reaction, makes its fuel on the spot (bombardment with neutrons turns it into a fissile isotope of uranium), and would generate little long-lived radioactive waste.
Nifty. Also expensive and complicated. But in principle it has been proven as possible in nuclear labs around the world.
With that in mind, there is a kernel of what looks like real news in the Telegraph's story – an enthusiasm high in the ranks of China's rulers to break free of nuclear business-as-usual. However the piece has a few holes in it, plus a bonus or two that look to be typos or simple errors in hearing what sources said. One in particular has proliferated in aggregator and blog sites in a vivid quote: it declares that these things are safe because "Fission dies the moment you switch off the photon beam." It's such a cool quote that a technoid site that appears to be a Wikipedia wannabe promptly picked it up and added it to its entry on Thorium Reactors.
It stopped me cold. A photon beam! Like a flashlight or in Brit-speak a torch? Huh? How would that keep a thorium reactor going? The mind spun and went nowhere.
The quote's cited source is one Professor Robert Cywinski of the U. of Huddersfield, an authority on neutron sources, including those using accelerators and the process called spallation. They aim intense proton beams at targets to spawn neutrons. At some risk, as I didn't actually call Dr. Cywinski, I declare he was misquoted and that this beam is no flashlight but a heavy-duty particle acclerator's output of protons. Whack that and a thorium reactor kept going on its diet of outside neutrons would, surely, go out.
Aside from this somewhat understandable garble, the piece refers to a "pebble-back" reactor. That's new to me. Pebble bed, I get. The author is the newspaper's international business editor. For all the muddled moments in it, and despite the hyperbolic suggestion that China is "running away" from the rest of the world with thorium, he produced a story of some substance on a field that is making the news generally. But surely an editor of some stature should have the sense to pause for a moment, after diving without much experience into such a technical arena after speaking it appears with a royal just back from China, might have run some of the geeky bits past a pertinent, uh, boffin.
And if by chance there are photon beams running a vital stage in thorium reactors, and pebble-back units waiting in the wings, Mr. Evans-Pritchard has my deep and mortified apologies.
Oh, one more thing. India has a very old and ambitious thorium reactor program as well and has been at it a lot longer with a larger budeget than has China. The Telegraph might have mentioned it. (Here's a fine IEEE Spectrum Q&A from a few years ago by Seema Singh with one of the leaders of that program.)
Other recent thorium reactor stories:
- Tucson Citizen – Jonathan DuHamel: Thorium, another alternative energy choice ; This is a column that goes by a notable running title: Wry Heat.
- Popular Mechanics – Is the "Superfuel" Thorium Riskier Than We Thought? ; Perhaps, it says here while referring to a paper in Nature, the proliferation risks are not so low after all.
- Business Insider – Lucas Kawa: Norway Set to Test the "energy Source of the Future."
Grist for the Mill: Energy from Thorium (a US-based advocacy organization) with its own report, from early 2011, on China's program (and source of this post's illus).
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