Plutonium reprocessing,breeder reactors,and decades of debate

Abstract

Some observers believe that plutonium reprocessing is on the verge of an expansion, while others argue that the end of the practice is in sight. The risk of nuclear proliferation has always been the chief objection to reprocessing but proponents argue that today, with uranium enrichment technology more easily available, reprocessing no longer represents an efficient route toward nuclear weapons. Supporters also tout the energy security that reprocessing could provide to nations without indigenous uranium sources and the reductions in high-level nuclear waste that reprocessing might achieve. Opponents counter that reprocessing offers only marginal benefits in waste reduction and in any event makes little economic sense. Here, Klaus Janberg of Germany (2015), Baldev Raj and P. R. Vasudeva Rao of India (2015), and Hui Zhang of China debate how nations—taking into account issues ranging from proliferation to waste to cost—should approach plutonium reprocessing.

The potential of fast breeder reactors to produce more fuel than they consume has held an attraction since the advent of nuclear power, especially to those who envision a time when uranium will no longer be available cheaply. Unfortunately, several decades of experience have shown that plutonium recycling systems are much more costly and much less reliable than water-cooled reactors. If establishing sustainable nuclear power means successfully managing issues such as nuclear safety and proliferation resistance while also achieving economic competitiveness, minimizing production of radioactive waste, and using natural resources wisely, breeder reactors and plutonium recycling still have far to go before they can meaningfully contribute.

In China, the closed fuel cycle has been an official element of nuclear energy policy since 1983. According to proponents, plutonium reprocessing and breeder reactors will allow full utilization of China’s uranium resources, drastically reduce the volume of radioactive waste that must be stored in an underground repository, and establish a way to dispense with the spent fuel accumulating in China’s reactor pools. But Beijing’s attempts to develop commercially viable reprocessing facilities and breeder reactors have been afflicted with technological difficulties, serious delays, and cost overruns. At this point—especially taking into account China’s ample uranium resources and its easy access to additional resources abroad—it appears very doubtful that reprocessing and fast reactors are the proper way forward for China’s nuclear energy sector.

Not according to plan

In 1986, China’s State Council approved construction of a pilot civilian reprocessing plant at the Jiuquan nuclear complex in Gansu province. Construction of the plant, designed to produce 50 metric tons of heavy metal a year, started in 1998 and finished in 2005. But the construction process encountered difficulties, delays, and higher-than-expected costs. Finally, a hot test was conducted in 2010—24 years after the project’s approval. Even then, after only 10 days of operation and the separation of less than 14 kilograms of plutonium, new problems were identified. As of the end of February 2015, reprocessing had not resumed. Indications are that the plant’s annual reprocessing capacity upon resumption could be much lower than the 50 metric tons of heavy metal originally planned.

Separately, the China National Nuclear Corporation (CNNC) has since 2007 been negotiating with France’s Areva on the purchase of a commercial reprocessing plant capable of processing 800 tons of heavy metal a year. A series of agreements has been signed but price remains a sticking point. And Chinese experts are not unanimous about whether China should import a commercial reprocessing plant at all. Some would like to fast-track the deal while others believe that China should prioritize indigenous technology in order to maintain independence. Indeed, even amid its negotiations with Areva, CNNC began to plan a medium-scale demonstration reprocessing plant, using the pilot plant as a basis. The proposal has not been approved by the government but in any event the future of the Areva deal is by no means clear.

Parallel with development of the pilot reprocessing plant, China has been working to establish commercially viable plutonium breeder reactors. According to a plan in place until 2013, development of breeder reactors was to be a three-stage process. The first stage was to complete a project known as the China Experimental Fast Reactor. The second stage would involve building a few demonstration fast reactors by about 2020. Finally, commercialized fast reactors would be deployed around 2030. Progress always ran far behind schedule.

The China Experimental Fast Reactor is a sodium-cooled experimental fast reactor using technology developed for Russia’s BN-600 reactor. The project, with a planned capacity of 20 megawatts, was approved in 1995. Construction began in 2000. As with the pilot reprocessing plant, the experimental fast reactor encountered many difficulties during construction. Capital cost estimates had to be adjusted twice, with each estimate double the previous one. The reactor went critical in July 2010 and by July 2011 40 percent of its full power was incorporated into the grid. The reactor, however, was online for only 26 hours during the remainder of 2011 and it produced the equivalent of just one full power-hour. Not until December 2014 did the reactor manage to operate at full capacity for 72 hours. So 19 years passed between project approval and operation at full capacity.

As for the second stage of the pre-2013 plan, CNNC in 2009 signed an agreement with Russia’s Rosatom to jointly construct two copies of Russia’s BN-800 fast neutron reactor in China. But Beijing has not officially approved the project. As with the French reprocessing plant, Chinese experts complain that Russia is demanding too high a price. It is not clear when or if the project will go forward. Instead, CNNC in 2013 began focusing on the development of the indigenous 600-megawatt China Fast Reactor (CFR-600). The start of construction is envisioned for 2017, with operations to commence in 2023—but the government has not approved the project yet.

Experts from CNNC have also, since 2013, urged the development of China’s first commercial fast reactor—a 1,000-megawatt reactor based on experience gained from the CFR-600. But CNNC expert Gu Zhongmao—an advocate of the closed fuel cycle—said at a recent workshop on nuclear energy in East Asia that “China needs at least another 20 to 30 years of effort before commercialization of fast reactor energy systems, and there are so many uncertainties ahead. It is beyond our ability to draw a clear picture 20 years ahead.”

Why rush?

Should China continue pursuing its plans for fast breeder reactors and commercialized reprocessing? Good reasons exist for avoiding this course of action.

First, because most of China’s power reactors are newly built, Beijing will face little pressure over the next two decades to reduce its spent fuel burden. And spent fuel can be stored safely, at low cost, in dry casks—or can be disposed of safely in a deep geological repository. Proponents of reprocessing often point out its ability to reduce volumes of nuclear waste—but reprocessing still produces high-level waste, long-lived intermediate waste, and low-level waste. All of these waste streams must eventually be buried, so reprocessing does not eliminate the need for repositories. Moreover, a geological repository’s capacity is determined by the waste’s decay heat, not by the physical volume of waste. Thus, at the geological repository for high-level waste that China envisions establishing in Gansu Province, capacity would merely double if all transuranic elements were separated from nuclear waste—the same increase that could be achieved by waiting 100 years before burying the waste. In the end, the capacity of geological repositories is increased to only a tiny extent by reprocessing plutonium and recycling it once via mixed oxide fuel.

Second, China will face no shortage of uranium resources in the foreseeable future. The nation’s identified resources more than tripled between 2003 and 2012, to 265,500 metric tons from 77,000 metric tons. China’s potential uranium reserves amount to more than 2 million tons. Beijing in recent times has also secured huge overseas uranium resources—about three times as large as its own identified uranium reserves. More such reserves could easily be added. (The global distribution of uranium resources can generally be characterized this way: Countries with more nuclear energy have less uranium, and countries with more uranium have less nuclear energy. So trade in uranium naturally constitutes a global market.) To the extent that China is concerned about potential disruptions in its uranium supply, it could easily and inexpensively establish a “strategic” uranium stockpile.

Regarding the price of uranium, past predictions that prices would steadily rise have been proven wrong—even when demand has increased, uranium prices have remained relatively low. This is unsurprising in a way. Prices for most minerals have decreased in constant dollars over the past century even as extraction has increased. For uranium, increased exploration and advances in technology have caused known resources to increase faster than uranium has been depleted. Known uranium resources are a dynamic economic concept, and global resources will surely prove to be greater in the long run than the amount currently reported in the Nuclear Energy Agency and International Atomic Energy Agency’s “Red Book” (International Atomic Energy Agency and Nuclear Energy Agency, 2014).

China should carefully examine the experiences of nations that have launched large reprocessing programs and built demonstration breeder reactors in the expectation that commercialization of these reactors would follow. Commercialization did not follow in those countries—but huge expenses were incurred for cleaning up reprocessing sites and disposing of separated plutonium. For China there is no urgent need to go down this risky road.

Plutonium recycling is much more expensive and much less safe and secure than operating light water reactors with a once-through fuel cycle. Dry-cask storage is a safe, flexible, and low-cost option for waste that can postpone for decades the need either to reprocess spent fuel or to dispose of it directly—allowing time for technology to develop. China has no convincing rationale for rushing to build commercial-scale reprocessing facilities or plutonium breeder reactors. Looking beyond China, if the safe and secure operation of nuclear power plants cannot be guaranteed today, what’s the point of maximizing uranium resources for future generations? In particular, what’s the point of doing so through breeder reactors and plutonium reprocessing—problematic technologies that introduce additional security risks?