TOKYO -- Supplies of uranium, used to fire nuclear power plants, are becoming increasingly plentiful globally, threatening to make redundant Japan's long-standing policy of recycling spent nuclear fuel.
A pillar of the policy is a joint project with France to develop a fast reactor, which generates electricity using spent nuclear fuel. But The French government recently informed Tokyo of plans to freeze the project amid rising uranium reserves. The surprise move has brought Japan's nuclear fuel cycle policy to a standstill.
Japan remains publicly committed to the program. "The development of a fast reactor will contribute to the effective utilization of resources and energy self-sufficiency," said an official in charge of the project at the Ministry of Economy, Trade and Industry at a government meeting on Dec. 3. But despite the remarks, the road map for developing a fast reactor announced by the ministry the same day does not give specifics on how the program will proceed.
That is because the French government had earlier informed Japan behind the scenes that was ending its participation in the project and would cease funding it in 2020, although it is likely to continue research on a fast reactor on a smaller scale.
Construction of nuclear power plants took off around the world in the 1960s, raising concerns that uranium reserves would be exhausted in the 21st century. Western countries and the Soviet Union saw fast reactors as crucial to the efficient reuse of fuel and competed to develop them.
Japan also made building a fast reactor central its nuclear fuel cycle policy in the 1950s, when it began moves to introduce nuclear power. Its flagship was Monju, a prototype fast-breeder reactor in western Japan. Breeder reactors produce more nuclear fuel than they consume. But Monju was hit by a spate of difficulties and the government decided in 2016 to decommission the reactor with little to show for its decades of effort and billions of dollars spent.
Japan then turned its attention to the French-led Advanced Sodium Technological Reactor for Industrial Demonstration, or Astrid, project. Japan has so far spent about 20 billion yen ($177 million) on the next-generation fast reactor project.
But Astrid stalled when the CEA, France's nuclear regulator, announced in June that the project would be scaled back. CEA's program manager, Nicolas Devictor, said at the time that building a demonstration reactor was not so urgent, given the state of the uranium market.
Then, on Nov. 27, French President Emmanuel Macron announced plans to reduce the country's reliance on nuclear power for electricity to around 50% from the current 70%. The Macron government has also concluded the fast reactor was not a priority and that cooperation between Japan and France on the project should be put on the back burner, citing an abundance of uranium.
According to a 2003 report by the Paris-based Organization for Economic Cooperation and Development, global uranium reserves totaled about 4.58 million tons, equivalent to about 85 years' worth of consumption at nuclear power plants. By 2016, the OECD said reserves had risen to 5.72 million tons, or more than 102 years of consumption.
The 2016 report also estimated that increased mining would push up global uranium reserves to 7.64 million tons, equal to more than 135 years worth of nuclear fuel.
There are two reasons for the uranium glut: the end of the Cold War and nuclear accidents.
In 1970, there were only about 840,000 tons of uranium left in the Western countries, raising fears of a shortage. But the end of the Cold War and technological innovation increased the supply of uranium.
Concerns about the safety of nuclear power, meanwhile, sapped demand. The explosion in 1986 at the Chernobyl nuclear plant in Ukraine and the meltdown at the Fukushima Dai-ichi nuclear plant in Japan in 2011 soured people on nuclear power around the world, putting the brakes on construction of new reactors in Germany and Switzerland.
The cooling enthusiasm for nuclear power has continued. Investment in the industry shrank 45% in 2017 from a year earlier, according to figures released by the Paris-based International Energy Agency in October.
Another factor pushing up supplies of uranium is a growing pile of plutonium, another nuclear fuel that is extracted through the reprocessing of spent fuel. That, coupled with the nuclear industry's slump, helps explain the uranium glut.
The plutonium surplus is a particularly serious headache for Japan. With many nuclear plants still shut down over safety concerns in the wake of the Fukushima disaster, the country's stockpile of plutonium has reached 47 tons.
Some have expressed concern that this plutonium could be diverted to make nuclear weapons. In response to U.S. criticism, Japan compiled new guidelines on the use of plutonium in July that call for reducing the country's plutonium stocks.
Japan's nuclear fuel cycle policy rests on two pillars: "pluthermal" power generation using plutonium as fuel at nuclear power plants, and a fast reactor that can consume large quantities of the stuff. But with the Monju plant mothballed and the fast reactor project with France fizzling out, it is unclear how the cycle can continue.
Maintaining a nuclear fuel cycle centered on a fast reactor is more expensive than operating ordinary nuclear plants that burn uranium. With the world awash in uranium, the commercial rationale for operating a nuclear fuel cycle has disappeared.
Countries such as Germany have canceled fast reactor development projects one after another. If France pulls the plug on its fast reactor, Japan's nuclear fuel cycle will be difficult to sustain. It will no longer need a spent nuclear fuel reprocessing plant and the spent fuel will have nowhere to go.
Japan is exploring the possibility of building a fast reactor with the U.S. But according to senior official at Japan's science and technology ministry, "It is unclear how serious the U.S. is about research on a fast reactor."