Nuke plant goes offline in middle of heat wave

In the midst of a nationwide heat wave, the Yeonggwang nuclear power plant No. 6 in South Jeolla, stopped operating due to a malfunction yesterday and Korea Hydro and Nuclear Power Corporation (KHNP), the operator of the country’s 21 nuclear reactors, said it wasn’t sure when it would go back online.

“The power plant was stopped after an alert signal for nuclear reactor protection was received at 2:57 p.m. yesterday,” according to KHNP.

The Ministry of Knowledge Economy said a malfunction seemed to be caused by a temporary power cut to the nuclear reactor.

KHNP said the outage had no impact on the safety of the power plant and didn’t signify any radioactive leak. “However, it is not clear when we will be able to resume operating the power generator,” said an official at the company. The company is investigating the cause of the malfunction and will wait for approval from the Nuclear Safety and Security Commission to restart the reactor.

The plant has the capacity to produce around 1 million kilowatts of electricity.

Thanks to the start of the vacation season in Korea this week, the drop in electricity reserves did go down below the critical level of 4 million kilowatts, according to the ministry.

“We won’t see a high electricity demand as many companies are taking vacations this week,” said the ministry in a press release. “We will be able to keep the electricity reserves in the 5 million to 7 million kilowatt range.”

At the peak time for electricity usage between 2 p.m. and 3 p.m. yesterday, which was before the generator’s malfunction, electricity reserves hit a low of 6.6 million kilowatts, according to an official at Korea Power Exchange. After the reactor stopped, reserves ranged from above 4 million kilowatts to 5.6 million kilowatts at 4:20 p.m. yesterday.

However, if the generator doesn’t go back online after the vacation period ends in mid-August, the power supply might become tight. As of yesterday, 19 nuclear plants are operating out of 23.

By Lee Sun-min [summerlee@joongang.co.kr]