• New governor uncertain about safety after April earthquake
  • Sendai facility is Japan’s only operating nuclear plant

Kyushu Electric Power Co. fell after voters in the prefecture where the utility operates a nuclear reactor elected a new governor who is demanding that the company’s atomic plant be temporarily halted because of safety concerns.

Fukuoka-based Kyushu Electric fell as much as 7.8 percent to 917 yen in Tokyo, the biggest intraday drop since June 24 and the lowest since April 2013. The shares were down 7.6 percent at 919 yen as of 9:19 a.m.

Satoshi Mitazono defeated 3-term incumbent Yuichiro Ito in Sunday’s gubernatorial race for the southern prefecture of Kagoshima, where Kyushu Electric’s Sendai nuclear power plant is located. Mitazono campaigned for the temporary closure of the reactors, citing uncertainty about safety after the April earthquake in nearby Kumamoto prefecture.

Kyushu Electric must take the reactors offline in the fiscal year ending March for required maintenance that lasts around three months. While not enshrined in law, local government approval -- including endorsement from the governor -- is traditionally sought by Japanese utilities before they return the plants to service.

Public opposition to nuclear power has slowed the restart of some reactors. A local court sided with a citizens’ group in March, issuing an injunction preventing the operation of Kansai Electric Power Co.’s Takahama No. 3 and 4 reactors. The court questioned whether evacuation plans and tsunami prevention measures -- which had been endorsed by the government -- were robust enough.

Kyushu Electric’s Sendai No. 1 and No. 2 units, which restarted last year, are currently the only reactors fully operating in Japan. A series of earthquakes in April, including a magnitude-7.3 tremor that struck about 119 kilometers (74 miles) from the Sendai nuclear facility, heightened criticism of the power plant.

Before it's here, it's on the Bloomberg Terminal. LEARN MORE