Japan’s government has set its first national target for rebuilding nuclear reactors since the 2011 Fukushima disaster: two to five new units by the 2040s. The decision was adopted at a meeting of cabinet ministers at the prime minister’s office on Friday, part of a revised energy policy meant to prepare for a power shortage the country can already see coming.
Japan’s reactors are designed to operate for about 60 years, and the fleet that survived the post-Fukushima reckoning is aging out. As old units are decommissioned, the gap in the power supply widens, and the government now projects the country will need to rebuild 11 to 14 reactors by the 2050s on top of the first wave. Prime Minister Sanae Takaichi said the government will move forward with policies to ensure investment in nuclear power plants and will promote programs to nurture the engineers and workers the industry lost over the past decade and a half. Industry Minister Ryoichi Akazawa outlined plans to reduce the burden on local governments that host reactors and to advance surveys by revising the basic policy for selecting final disposal sites for high-level radioactive waste.
It is the first time the government as a whole has set a target for rebuilding nuclear plants since the triple meltdown at the Fukushima No. 1 plant in 2011, when the country effectively abandoned the idea of building new reactors and spent the next decade and a half restarting old ones, one safety review at a time. The new guidelines still place the reconstruction of Fukushima Prefecture and the decommissioning of the damaged plant at the top of the agenda.
In its basic energy program adopted at a cabinet meeting in February 2025, the government declared a policy of maximum use of nuclear power and set a target of raising nuclear’s share of the power supply mix to about 20 percent in fiscal 2040. Friday’s decision turns that preference into a number: not just restarts, but rebuilds, planned and budgeted for.
High-level radioactive waste needs a final disposal site, and no community wants it. The government’s plan is to revise the basic policy and advance surveys, so the search for a site continues. Until a site exists, every new reactor built today is a promise to a future generation that someone will solve the waste problem, and the promise has been broken for decades.
Japan is planning nuclear power openly again. The reasons are arithmetic, not ideology: the old reactors are retiring, the grid will need power, and the alternatives are not ready. The waste question remains unanswered, and the government’s first announced step was a survey, not a construction site.