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- By John Hewitt on December 18, 2012 at 12:12 pm
- 40 Comments
The enrichment of natural uranium is the first and perhaps most difficult step to building nuclear weapons. LWRs, which by their nature require enriched uranium, were the logical choice at the dawn of the nuclear age to develop an industry around. Richard Martin, a writer for Wired and author of Superfuel: Thorium, the Green Energy Source for the Future, summarized the argument a little more succinctly: the US abandoned thorium reactors because they didn’t produce plutonium bombs. The larger truth, of course, is a little more complex.
Today’s nuclear industry might be described as an elephant. It would be very difficult for an elephant to evolve wings (thorium) because big animals just do not evolve wings — little animals evolve wings and they in turn might evolve into bigger animals with wings. The chosen gimmick of the proto-elephant was the trunk (uranium), at first just a little one, but as elephants got larger, their trunks got really really large; it became their defining feature.
The molten salt reactor (MSR), predecessor of the LFTR, lost out to the LWR in the early ’50s for a simple reason. When Navy Admiral Hyman Rickover got wind of the possibilities of nuclear power, he wanted and got nuclear-powered submarines. Unfortunately for the MSR, sodium would react violently if it accidentally contacted water. The baby nuclear elephant would be a small machine, but light water uranium reactors, which already had a little head start, would be the technology. It also didn’t help the case for MSRs that naval and shipyard engineers were already the best in the world at working with water. They were experts at building the corrosion resistant pumps, valves, bearings and other machinery needed to utilize it. But as Martin keenly observes in Superfuel, five decades later we see that the essential element of today’s technology, pressurized water, has become its Achilles heal.
Weinberg continued to pour his efforts into a small, workable MSR to be used as a powerplant for a nuclear airplane. This was an unfortunate misdirection. In a time when there were actual plans to use nuclear technology to dam the Straight of Gibraltar and reclaim lands long ago submerged under the Mediterranean, the idea of a nuclear airplane was not so absurd. The Cold War not withstanding, in times of prevailing peace, a flying nuclear reactor cannot count its first success as managing not to crash and destroy itself. The US and Russia ran similar programs and flew test reactors on board conventional aircraft, but ultimately both projects were scrapped.
Many people think it is not too late today, to attempt put some muscle into Dumbo’s ears so to speak, and revisit the thorium reactor. Several private efforts in the US have sprung up, led by entrepreneurs who have the knowledge necessary to do so. One project undertaken by Terrapower, funded through Microsoft’s Intellectual Ventures, is trying to build a device called a travelling wave reactor. It is a little more exotic than the MSR technology from decades ago and will require considerable effort to realize. Other homegrown efforts by start-ups like Flibe Energy, Thorium Power, and Lightbridge are struggling to fund their projects without visible government support.
Flibe Energy is looking to make ends meet by exploiting the fact that LFTRs are very good at producing medical isotopes like molybdenum-99, 90% of which we currently import from Canada. Our looming medical isotope problem is irresponsible and inexcusable as these isotopes are critical to patient diagnoses and treatment. Any health care system which fails to provide for their reliable procurement will only accelerate current medical cost inflation. Transatomic is another US-based company scrapping to survive. It is now running tests using the IR-8 research reactor at the Kurchatov Institute in Moscow. Thorium Power, based outside of Washington DC, is also working with Russian scientists to use thorium fuel — not to directly generate energy, but instead to burn surplus military plutonium.
Observing the struggle of these groups just to raise capital, one might ask how the US could possibly develop thorium power on our soil if we can’t even dig up rare earths? The reason why we can’t dig up monazite deposits which contain abundant rare earths is because the ores are “contaminated” with too much, well — thorium. Apparently regulations on handling thorium — actually a rather mild, low-alpha emitter — are restrictive to the point of being prohibitive.
Efforts to organize a strategic thorium reserve in our country for future use by someone, or anyone, have emitted a plaintive cry largely lost in a system dominated by shortsighted policy and shareholder obligation. Just as our regulatory policy guarantees China’s supremacy in rare earths, so it does for thorium. Meanwhile, that which a mining company in our country must expensively handle as radioactive waste, stabilize in concrete, and return to a landfill, China is cherishing and funding with a five-year reactor plan to the tune of half a billion dollars. The industry sentiment, “if we like foreign oil dependency, we are going to love foreign nuclear technology dependency,” needs to be taken to heart.
India has shown the greatest long term commitment to thorium power, and perhaps represents perhaps its future even more than China. In 1974 India tested a nuclear bomb made from plutonium extracted from spent reactor fuel. Governments around the world were forced to face the realty of large scale commercial reprocessing. India never signed the Nuclear Proliferation Treaty and was barred from international trade in nuclear technology until 2006. With the world’s most abundant thorium deposits, the country initiated a long-term plan to integrate thorium fuel reactors into its comprehensive nuclear strategy, and now hopes to have its first successes within a few years.
The thorium power industry today is highly dynamic. New players, like Thor Energy in Norway, can burst on the scene and capture world attention within a short time. Recently the journal Nature published a pair of noteworthy articles on thorium power. One of them noted that in spite of its obvious safety advantages, thorium is not a route to a nuclear future that is completely immune to proliferation risks. The authors detailed pathways by which thorium could in theory be transmuted into feedstock for nuclear weapons. They called on the larger community to independently corroborate their analysis and institute necessary oversights. The geopolitical implications for thorium energy demand that the US be more that a spectator of the serious sport it founded — we must also be part player, and part referee to the extent that which we still can.
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