Ikata nuclear plant ((Photo Newsliner/CC BY-SA 2.5)Japan’s Shikoku Electric Power Company said on 12 October that it had applied to the Nuclear Regulation Authority (NRA) for formal permission to decommission unit 2 at its Ikata NPP in Ehime Prefecture, a 538MWe pressurised water reactor (PWR).

Shikoku Electric decided in March to decommission the unit, which began commercial operation in 1982 saying the expected costs of measures needed to meet new regulatory and safety requirements would make the unit uneconomical. Its 40-year operational licence will expire in 2022, the company said. Asahi Shimbun put the cost of the upgrades to Ikata 2 at around $1.89bn. In 2016, Shikoku Electric had decided to decommission Ikata 1 (also a 538MWe PWR) for similar reasons.  

The permanent closure of several other small older units had previously been decided after the Ministry of Economy, Trade and Industry's Agency for Natural Resources and Energy, revised the accounting procedures for the calculation of decommissioning costs. These included Kansai Electric Power Company's Mihama 1 (320MWe) and 2 (470MWe) PWRs  in Fukui Prefecture; Japan Atomic Power Company's 341MWe Tsuruga 1 boiling water reactor (BWR) in Fukui Prefecture; Kyushu Electric Power Company's 529MWe Genkai 1 PWR in Saga Prefecture; and Chugoku Electric Power Company's 429MWe Shimane 1 BWR in Shimane Prefecture.

 In December 2017, Kansai announced that it would not seek permission to restart Ohi 1&2 in Fukui Prefecture (both 1175MWe PWRs). Then at the end of September 2018, Tohoku Electric Power Co said that it was considering decommissioning unit 1 at its Onagawa nulcear plant in Miyagi Prefecture, a  524MWe BWR, which began operation in 1984.


Photo: Ikata nuclear power plant  (Photo Newsliner/CC BY-SA 2.5)