Japan has agreed to work with a U.S. company in technological cooperation to develop a sodium-cooled fast reactor.

People involved in the project stress that the new technology will contribute to the goal of a carbon-free society. But the government should not eschew reality-based debate on the future of existing nuclear power reactors.

The Japan Atomic Energy Agency, Mitsubishi Heavy Industries Ltd. and other Japanese entities will cooperate with TerraPower LLC’s project to build a fast reactor in the U.S. state of Wyoming. 

Fast reactors are more resource efficient as they can burn types of nuclear fuel that cannot be used at conventional reactors.

TerraPower’s reactor will use liquid sodium as a cooling agent such as the Monju prototype fast-breeder reactor, which Japan decided to decommission after a series of accidents.

Japan can provide meaningful support to develop a new type of reactor and maintain related technology by offering what it has learned from its experiences including failures.

Japan has been promoting the concept of recycling separated plutonium back into fuel for nuclear power generation. Fast reactor technology to burn plutonium is at the core of this strategy.

But this program has suffered setbacks, including the decision to scrap Monju and a lack of progress in the government’s plan to burn so-called MOX (mixed oxide) fuel, which is usually plutonium blended with natural uranium, in conventional nuclear reactors.

The government also considered participating in France’s Advanced Sodium Technical Reactor for Industrial Demonstration (ASTRID) project to build a prototype sodium-cooled nuclear reactor.

But the idea was dropped after the French government decided to scale down the project.

The nuclear fuel recycling program, which has gone awry, should be abandoned. The participation in the TerraPower project should not allow the government to delay the decision on the program.

The technological cooperation with the United States has been touted as a way to “contribute to the achievement of carbon neutrality.”

However, it is unclear whether this will help Japan achieve its goal of net zero emissions of greenhouse gases by 2050.

TerraPower plans to start operating the new reactor in 2028. But this technology cannot be used immediately in Japan, which has been developing fast reactor technology for a different type of fuel.

The government’s road map for the development of fast reactor technology, determined in 2018, offers no clear time frame for practice use. It only said full-scale operation is expected “sometime in the late 21st century.”

The government has cited the development of next-generation reactor technology, such as small modular reactors and fast reactors, as an important factor for its clean energy and “zero carbon” policy efforts.

But it has failed to offer a clear vision for the future of existing nuclear reactors despite its massive reservoir of experience and expertise.

The government’s new Basic Energy Plan, unveiled last year, says nuclear power should account for 20 to 22 percent of the nation’s total electricity output in fiscal 2030. But the document did not refer to any specific measure to hit the target.

Neither Prime Minister Fumio Kishida nor members of his Cabinet have been eager to discuss this issue, apparently because of a reluctance to engage in debate on sticky issues concerning nuclear power.

Fast-breeder reactors, which can theoretically produce more fuel than they use, were once advertised as a source of “dream energy” for a resource-poor Japan.

Following the Monju debacle, the government started stressing that nuclear fuel recycling and fast reactor technology can help reduce high-level radioactive waste. Now, policymakers are singing the “carbon neutrality” theme.

The government should stop trying to obscure problems with its nuclear power policy by promoting a new technology without clear prospects for practical use under a new slogan.

Instead, it should launch a reality-based debate on existing nuclear reactors in line with its pledge to reduce the nation’s dependence on nuclear energy as much as possible.

--The Asahi Shimbun, Jan. 28