Japan plans up to 5 new nuclear reactors by 2040

Up to 14 reactors may be replaced by 2050.

Japan’s industry ministry has drafted a plan to rebuild 2–5 nuclear reactors by the 2040s to maintain stable electricity supply as aging plants are retired, PNA reported.

The proposal marks the first time since the 2011 Fukushima disaster that the government has set a numerical target for reactor replacement. It comes as older reactors, many operating for 60 years or more, are progressively being decommissioned, raising concerns about future generation capacity.

The plan, presented to a subgroup of the Advisory Committee for Natural Resources and Energy, outlines the need to rebuild an additional nine reactors by 2050. This would bring the total number of replacement reactors to between 11 and 14.

Officials estimate that Japan will need between 2.2 million and 5.5 million kilowatts of replacement capacity in the coming decades to avoid a significant drop in power supply, particularly after 2040.

The draft also emphasises the continued safe decommissioning of the Fukushima No. 1 nuclear power plant operated by Tokyo Electric Power Company Holdings Inc. in Fukushima Prefecture, describing it as the government’s top priority. It further highlights plans to develop next-generation reactors designed to be safer than existing models.

Japan’s energy policy has shifted in recent years. In February 2025, the government approved a new basic energy plan calling for maximum utilization of nuclear power, reversing earlier post-Fukushima efforts to reduce reliance on the technology.

Under current targets, nuclear energy is expected to account for about 20% of Japan’s electricity mix by fiscal 2040, up from 9.4% in fiscal 2024.