The worst of the summer heat may be over, but the nation is still on guard for a potential blackout next month as several thermoelectric and nuclear power plants face temporary shutdowns for repairs and maintenance.

Regional power suppliers are currently planning to halt the operation of some 14 or more steam power plants consecutively for maintenance reasons, according to the Ministry of Trade, Industry and Energy.

Two nuclear power plants will also follow suit, in which case seven out of 23 nuclear facilities will be dormant.

It is the usual practice for power suppliers to schedule their preventive maintenance measures in the spring and fall, during the low electricity seasons, officials said.

“We are considering rescheduling the regular suspension as a late summer heat is expected during the first few weeks of September,” said an official of the Korea Power Exchange.

“But the problem is that several reactors are in urgent need of overhaul, due to the excessive use during the electricity crisis this summer.”

The corresponding plants, when combined, have the total capacity of producing over 8 million kilowatts.

“Considering that the suspension is to take place consecutively, not simultaneously, the actual blow will not be as vital,” the KPX official said.

Authorities are nevertheless tense over the supply reduction as just a few million kilowatts may seriously affect the entire nation’s power level.

Even after what the ministry said would be the worst and the last of this summer’s heat wave, the KPX had to raise the power supply alarm repeatedly as the backup power level fell below the 5-million-kilowatt line.

“We have overcome the worst part but will continue to keep up our guard (against a possible electricity crisis),” said Minister Yoon Sang-jick last week.

Also, it was in mid-September when the nation was hit with an unprecedented power shortage, which resulted in a temporary power shutdown and caused hundreds of billions of won in damage.

By Bae Hyun-jung (tellme@heraldcorp.com)