Japan planning to increase its share of nuclear generation from 5% to over 20%

7th May 2024 | Source: The Global Energy Association

The photo is sourced from nuclear-news.net

In order to increase the share of nuclear in Japan’s energy mix from the current 5% to 20–22%, the country will need to restart 11.4 gigawatts (GW) of nuclear reactor capacity between 2025 and 2030. This assessment was provided by the U.S. Energy Information Administration (EIA) based on the analysis of the prospects for achieving the goals of nuclear energy development set out in Japan’s GX Decarbonisation Power Supply Bill, which came into force in 2024.

Nuclear power plants (NPPs) used to provide just under 30% of Japan’s power output before the Fukushima Daiichi accident in 2011. Following the accident, Japanese regulators decided to suspend operations at all NPPs without exception, which is why the share of domestic nuclear generation dropped to zero by 2014. The restart of the reactors began in 2015: as of today, 12 power units are generating electricity on a regular basis, and another two – the second power unit of the Shimane NPP on the island of Honshu in southern Japan and the second power unit of the Onagawa NPP in the northeast of the country – will resume operation before the end of this year. As a result, the available capacity of Japan’s NPPs will rise to 12.6 GW.

In addition to the two aforementioned power units of the Shimane and Onagawa NPPs, three more reactors have been given the right to recommissioning: the first power unit of the Tokai II NPP on the Pacific coast and the sixth and seventh power units of the Kashiwazaki-Kariwa NPP on the coast of the Sea of Japan. Another eight decommissioned reactors are awaiting regulatory approval, including the first power unit of the Higashidori NPP and three power units of the Tomari NPP in northern Japan; as well as the second power unit of the Shika NPP, the second power unit of the Tsuruga NPP and the third and fourth power units of the Hamaoka NPP located in the central part of the country.

According to the IAEA, the overall net capacity of the aforementioned 11 power units is 11.1 GW, while the total capacity of the reactors under construction – the first power unit of the Oma NPP and the third power unit of the Shimane NPP – is 1.7 GW. This means that the capacity of the decommissioned and under-construction reactors will be sufficient to increase the share of nuclear generation in Japan from 5% to 20–22%. At the same time, a policy document of Japan’s Cabinet of Ministers last year called for the construction of innovative next-generation reactors to replace NPPs that had been completely decommissioned (without the possibility of restarting, as in the case of the Fukushima Daiichi NPP). One example is the Generation III+ reactors, which are equipped with passive safety systems that make it possible to shut down the reactor without any operator intervention or external power sources.