Korean regulators approved the restart of unit 4 at the Hanwool nuclear plant on Monday, providing limited relief for a power shortage during the most high-demand time of year.
Outages at six reactors have left Korea facing the potential for nationwide blackouts, the Yonhap news service reported. With South Korea's electricity consumption expected to reach its yearly peak this week, grid operators have seen the country's power reserves briefly dip below a 4,000 megawatt benchmark. Government forecasts for peak hours predicted reserves could drop as low as 1,800 megawatts, although power conservation efforts have helped keep demand from outstripping supply so far.
An unplanned outage Monday at a 500 megawatt gas plant made the situation worse, while the bulk of the shortage stems from outages at Korean nuclear plants. Twenty three reactors normally provide about a third of the country's power, according to the World Nuclear Association. Four units have been out of service for routine inspections and maintenance. Power supply problems emerged in May when the government shut down additional units at the Shin Wolsong and Shin Kori plants amid a bribery and quality control documentation scandal. Two were taken offline and a third was forced to extend a maintenance outage to replace cabling with questionable documentation. Newly built Shin Wolsong 2 has not been allowed to enter service.
Hanwool 4, which can now restart, has been idle for more than a year because of problems with its steam generator.