The loading of fuel assemblies into the core of unit 3 at the Ohi nuclear power plant in Japan’s Fukui Prefecture will begin tomorrow, Kansai Electric Power Company announced. The utility plans to return both units 3 and 4 at the plant to commercial operation by mid-2018.
Ohi units 3 and 4
Following the shutdown of all of Japan’s reactors after the March 2011 accident at the Fukushima Daiichi plant, Ohi 3 and 4 were given permission to resume operation in August 2012. However, the two 1180 MWe pressurised water reactors (PWRs) were taken offline again for Nuclear Regulation Authority (NRA) inspections in September 2013.
Under Japan’s reactor restart process, plant operators are required to apply to the NRA for: permission to make changes to the reactor installation; approval of its construction plan to strengthen the plant; and, final safety inspections to ensure the unit meets new safety requirements. Operators are required to add certain safety-enhancing equipment within five years of receiving the NRA’s approval of a reactor engineering work programme.
Kansai submitted its construction plan application for Ohi 3 and 4 in July 2013. The NRA approved the plan for strengthening the units in August last year.
Following pre-operation inspections of the units to confirm that the safety countermeasure equipment complies with the approved construction plan at the plant, Kansai is now set to start loading fuel into unit 3 ahead of its restart. In November, the utility said it expected to restart the reactor around mid-March, with commercial operation scheduled from early-April.
The governor of Japan’s Fukui Prefecture approved the restart of Ohi units 3 and 4 in November. Unit 4 is also expected to be restarted in the coming months. Kansai earlier said it expects to refuel the reactor in mid-April, restart it around mid-May, with commercial operation expected to resume in early June.
In December, Kansai announced that it will not seek permission to restart Ohi units 1 and 2, which have been offline since July 2011 and December 2011, respectively. The company will now apply to decommission the two 1175 MWe PWRs, which are approaching 40 years old.
Of Japan’s 42 operable reactors, five have so far cleared inspections confirming they meet the new regulatory safety standards and have resumed operation. These are: Kyushu’s Sendai units 1 and 2; Shikoku’s Ikata unit 3; and Kansai’s Takahama units 3 and 4. Another 19 reactors have applied to restart.