Unit 4 at Kyushu Electric Power Co’s Genkai nuclear plant in Japan’s Saga Prefecture was restarted on 16 June.

Genkai 4 is the ninth reactor to go back online since stricter safety rules were adopted following the 2011 Fukushima nuclear accident. The Genkai plant faced a series of problems in the lead-up to the restart.

In May, pumps installed to control coolant circulation at Genkai 4 malfunctioned  after Genkai 3 experienced a steam pipe leak following is restart in March. Kyushu Electric estimates that restarting the two units will save it JPY11bn a month ($99m) by reducing the need for fossil fuels.

Genkai 4 was cleared to restart by the Nuclear Regulation Authority in January 2017 and in March 2018 the Saga District Court rejected a request for an injunction against the plant’s operation.

The 1180MWe pressurised water reactor is expected to begin generating electricity again on 20 June, with commercial operation scheduled for mid-July.

Map showing current status of Japanese reactors