Japan’s Ministry of Economy, Trade and Industry has issued a draft policy proposal recommending the reconstruction of 14 ageing nuclear reactors by 2050, representing 16 GW of cumulative capacity (Kyodo News, 05/06/2026). The country plans to rebuild between two and five reactors by the 2040s and 11 to 14 by the 2050s. The proposal aims to secure a stable domestic electricity supply that would address a projected increase in electricity demand, which is largely driven by AI data centres, and would also curb costly fossil fuel imports.
According to Enerdata’s Global Energy and CO2 Data, 61% of Japan’s power mix consisted in thermal sources (gas 31%, 28% of coal and 2% of oil) in 2025, exposing the country to international fuel-price volatility.
Following the Fukushima accident in 2011, all undamaged nuclear reactors were placed offline for safety controls. Before the accident, there were 54 reactors spread over 17 plants. As of June 2026, 15 of the 42 operable reactors have been restarted.
Under the country’s current national energy plan, Tokyo aims to double the share of nuclear power in its electricity mix to around 20% by the fiscal year of 2040 (10% in 2025).
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