Nuclear power is in decline around the world. Globally, nuclear power provides about 11 percent of electricity generated (in kilowatt hours), down from its historic maximum of 17.6% in 1996. Even the International Atomic Energy Agency's projections for the future have been declining steadily and now project nuclear power as constituting 2 to 5.4% of the world's installed electricity generation capacity (in megawatts) in 2050, down from 6.5% in 2013. Despite sustained interest on the part of the politicians and governments, nuclear power has not even maintained market share, let alone grow.
Despite this reality, some nuclear enthusiasts continue to believe that eventually nuclear power would make a comeback and grow so much that the world will run out of uranium that is needed to fuel nuclear reactors. And so, they say, the world would have to construct what are called breeder reactors that would produce more fuel than they consume. This, they argue, is necessary not just to avoid running out of uranium but also make nuclear energy "sustainable" in the long term.1 In line with that very environmental term and the constant effort to greenwash nuclear power, they also use the term recycling to talk about the use of plutonium as fuel.
This view is not new. It is nearly as old as nuclear power, and was widely prevalent and advocated by leading scientists and engineers in multiple countries. For example, in 1953, Franz Simon, a British physicist, wrote, "if we had to rely solely on the amount of [uranium-235] ... available in the known high-grade ore deposits, large scale power production would not be possible ... the real hopes for larger scale power production lie ... in the possibility of making use of uranium 238 or of thorium by the process of 'breeding'. While there is yet no absolute certainty that this can be done the probability is nevertheless high."2 Another physicist, Aleksandr Ilich Leipunskii, promoted breeder reactors in the Soviet Union using an argument that simply presumed that there would be a deficit of uranium resources for the future development of the nuclear industry.3
The expectation that it would become essential to fuel breeder reactors with plutonium was the original rationale for the reprocessing plants constructed in the 1960s and 1970s. With the benefit of hindsight, we can see that the early assumption about limited uranium availability was wrong. Indeed, even by the late 1970s, geologists had come to the conclusion that there were very large quantities of uranium ore available, and if one were to mine poorer grades of ore, there is an "approximately a 300-fold increase in the amount of uranium recoverable for each tenfold decrease in ore grade".4 A recent comprehensive review of global uranium resources concludes that, "there is a strong case for the abundance of already known U resources, whether currently reported as formal mineral resources or even more speculative U sources, to meet the foreseeable future of nuclear power".5 The range of futures considered in this assessment includes an extrapolation of the International Energy Agency's scenario to meet an atmospheric CO2 concentration of 450 ppm that calls for deploying about 2000 GWe of nuclear power by 2100. In addition to not running out of uranium, there has not also been any major increase in the price of uranium.
In the meantime, experience with breeder reactors around the world has shown that most have had persistent reliability problems, primarily because of their use of molten sodium as coolant.6 The capital costs of breeder reactors have been consistently higher than those of light water reactors; further, their capacity factors have been much lower. As a result, electricity from these reactors was even more expensive than nuclear power from light water reactors. As a result, no country has commercialized breeder reactors and only a few demonstration reactors have been built.
France, the country that is most reliant on nuclear power in the world, did try to commercialize breeder reactors after operating pilot scale and demonstration reactors. The Superphenix started operating in 1986, experienced a series of accidents, and was shut down in 1997.7 During this period it generated less then 7% of the electricity of what it could have done at full capacity. Currently, only a few demonstration reactors are being built or operated. With the exception of Russia and India, no other country has firm plans to deploy breeder reactors during at least the next couple of decades.
For all these reasons, the original rationale for reprocessing of spent fuel proved mistaken. But the die had been cast and reprocessing persisted in France, Japan and the United Kingdom. In an effort to find a rationale for continuing reprocessing, the French nuclear establishment proposed using the plutonium as supplementary fuel for conventional light water reactors. Because plutonium oxide is extremely carcinogenic if inhaled, MOX fuel, unlike uranium fuel, must be fabricated in sealed glove boxes. Even excluding the cost of reprocessing, the cost of MOX fuel fabrication is greater than the cost of the uranium fuel that it replaces. Including the cost of reprocessing, MOX fuel costs about ten times more. Again, the second rationale for reprocessing of spent fuel died in the face of economic realities.
Unfortunately, there are still holdouts, the most bizarre example of which is the Japanese nuclear village, the loose conglomeration of institutions that make nuclear policy in Japan. Even though there is enormous uncertainty about future of Japan's nuclear reactor fleet and about how to dispose of its already huge stockpile of separated plutonium, the nuclear village continues to be interested in starting operations at the Rokkasho Reprocessing Plant to separate out even more plutonium from spent power reactor fuel.
This persistence will be dear. In 2011, Japan's Atomic Energy Commission estimated that operating the plant would increase the electricity bills of Japan's ratepayers by about ¥7 trillion (US$60 billion) over the next 40 years.
With the failure of their first two justifications, reprocessing advocates have offered a third: facilitating spent fuel disposal. The argument is that plutonium and the other transuranic elements in spent fuel should be fissioned into mostly shorter half-life radioisotopes to reduce the long-term hazard from spent fuel. The reactors being proposed for the "burning" of plutonium and other transuranics, however, are modified versions of the costly and unreliable reactors that previously were being proposed for plutonium breeding. A U.S. National Academy review of a proposal to revive reprocessing and sodium-cooled reactors programs in the United States on this basis concluded in 1996 that "none of the dose reductions seems large enough to warrant the expense and additional operational risk of transmutation."8
Despite all the fond hopes of nuclear establishments around the world, reprocessing is not going to be a solution to the production of nuclear waste. Indeed, it may make it more difficult to solve. Reprocessing plants produce multiple waste streams; these are usually classified on the basis of their radioactive content. So-called low level waste, which has low concentrations of radioactivity but comprises over 80% by volume of the waste stream, is a major problem in terms of management. Because it is produced in such large volumes, nuclear establishments around the world find it expensive to store them and, so release them into the environment after some treatment. But nevertheless, this radioactivity makes it way into marine life and can be detected far away from the source.9
In addition to the economic and environmental arguments against reprocessing laid out above, there is another important reason to be concerned about the practice of reprocessing: that plutonium can be used to make weapons. Practically any kind of plutonium is considered weapon usable. Some make the distinction between weapon-grade plutonium that contains more than 90% of plutonium-239, and reactor-grade plutonium that has increased fractions of the higher isotopes of plutonium. A commonly cited problem with the use of reactor-grade plutonium is the increased risk of a "fizzle yield", where a premature initiation of the fission chain reaction by neutrons emitted by fissioning of plutonium-240 leads to pre-detonation of the weapon and an explosive yield only a few percent of the design value. However, as the U.S. Department of Energy has noted:
"At the lowest level of sophistication, a potential proliferating state or sub-national group using designs and technologies no more sophisticated than those used in first-generation nuclear weapons could build a nuclear weapon from reactor grade plutonium that would have an assured, reliable yield of one or a few kilotons (and a probable yield significantly higher than that). At the other end of the spectrum, advanced nuclear weapon states such as the United States and Russia, using modern designs, could produce weapons from reactor grade plutonium having reliable explosive yields, weight, and other characteristics generally comparable to those of weapons made from weapons-grade plutonium."10
The International Atomic Energy Agency assumes that 8 kilograms of plutonium would suffice for a first-generation nuclear weapon of the kind that was exploded on Nagasaki in 1945. The 8 kilograms includes inevitable losses during the production process. On this basis, the world's current plutonium stockpile is adequate for 30,000 weapons. Do we really need more?
The problems with reprocessing discussed above are not new. Over the decades, there has been increasing appreciation of the dubious nature of the arguments for reprocessing, and a steady decline in the number of countries that reprocess. As shown in a recent International Panel on Fissile Materials report11, the world is getting closer to the end of reprocessing spent fuel and separating plutonium.
M. V. Ramana is with the Program on Science and Global Security at Princeton University. He is co-editor of the recently published report: 'Plutonium Separation in Nuclear Power Programs: Status, Problems, and Prospects of Civilian Reprocessing Around the World', http://fissilematerials.org/blog/2015/07/new_ipfm_report_plutonium.html
References:
1. Baldev Raj and P. R. Vasudeva Rao, "For Sustainable Nuclear Energy, a Closed Fuel Cycle," Bulletin of the Atomic Scientists, April 9, 2015, http://thebulletin.org/reprocessing-poised-growth-or-deaths-door8185.
2. Franz E. Simon, "Nuclear Power: A British View," Bulletin of the Atomic Scientists IX, no. 4 (May 1953): 125.
3. Paul R. Josephson, Red Atom: Russia’s Nuclear Power Program from Stalin to Today (New York: W. H. Freeman and Company, 2000), 50.
Kenneth S Deffeyes and Ian D MacGregor, "World Uranium Resources," Scientific American, January 1980, 68.
5. Gavin M. Mudd, "The Future of Yellowcake: A Global Assessment of Uranium Resources and Mining," Science of The Total Environment 472 (February 15, 2014): 604, doi:10.1016/j.scitotenv.2013.11.070.
6. IPFM, "Fast Breeder Reactor Programs: History and Status" (Princeton: International Panel on Fissile Materials, 2010); S. Rajendran Pillai and M. V. Ramana, "Breeder Reactors: A Possible Connection between Metal Corrosion and Sodium Leaks," Bulletin of the Atomic Scientists, April 15, 2014, 0096340214531178, doi:10.1177/0096340214531178.
7. WISE, "Superphénix Definitely Dead: A Post-Mortem," WISE News Communique 475 (1997); NUKEM, "Is the Superphenix Dream Over...Or Over Yonder?," NUKEM, March 1997.
8. National Research Council, Nuclear Wastes: Technologies for Separations and Transmutation (Washington, D.C.: National Academy Press, 1996), 3.
9. NRPA, "Discharges of Radioactive Waste from the British Reprocessing Plant near Sellafield" (Norwegian Radiation Protection Authority, 2002); A. Baburajan et al., "Radionuclide Ratios of Cesium and Strontium in Tarapur Marine Environment, West Coast of India," Indian Journal of Marine Sciences 28 (1999): 455–57.
10. DoE, "Nonproliferation and Arms Control Assessment of Weapons-Usable Fissile Material Storage and Excess Plutonium Disposition Alternatives" (Washington, D. C.: U.S. Department of Energy, 1997), 37–39, www.osti.gov/scitech/biblio/425259.
11. IPFM, "Plutonium Separation in Nuclear Power Programs: Status, Problems, and Prospects of Civilian Reprocessing Around the World" (Princeton: International Panel on Fissile Materials, 2015).