Record heat wave puts government, KEPCO on emergency power footing

Power authorities have activated emergency response measures as a record-breaking heat wave grips the country. Officials are closely monitoring the electricity supply-demand situation, particularly as demand is forecast to set an all-time high during the third week of this month.

According to the Korea Power Exchange, peak demand Monday is expected between 6 and 7 p.m., reaching 88.9 GW.

The supply reserve margin during that period is projected at 16.2 GW, or a reserve rate of 18.2 percent, indicating a stable supply-demand balance.

The supply reserve rate is calculated by dividing the supply reserve — available capacity minus current demand — by peak demand, and serves as a measure of how much buffer the power grid has.

A reserve rate above 10 percent is generally considered stable. On July 13, peak demand reached 92.9 GW and the reserve rate fell to 11 percent, but it has remained higher since. During July 27 through July 30, when peak demand stayed in the 90 GW range, the reserve rate held between 14 and 15 percent.

"There appear to be no generation problems relative to current demand," a power authority official said. "During summer, we work to keep generators from going offline for maintenance or other reasons as much as possible, while securing reserve capacity."

As the heat wave intensifies, however, power consumption driven by cooling demand continues to grow. Monthly average peak demand jumped from 71.5 GW in June to 83.9 GW last month, and stands at 82.9 GW so far this month.

The Ministry of Climate, Environment and Energy earlier projected that power demand could climb to between 94.1 GW and 98.8 GW during the third week of August. If that forecast holds, it would surpass the 2024 record of 97 GW to set a new all-time high.

The ministry said supply management would not be a problem even if demand reaches the projected peak.

The government has expanded this summer's power supply capacity to 107 GW, up 2 GW from last year, and said that even if peak demand hits 98.8 GW, the reserve margin of 8.2 GW would remain at a "manageable level."

An additional 8.8 GW in reserve resources has also been prepared in case the margin falls short, the ministry said.

Power authorities run the numbers around the clock to prevent large-scale blackouts that can occur when cooling demand surges in summer. The key risk factor is a supply-demand mismatch — blackouts happen when peak demand is miscalculated or when sufficient supply cannot be secured to meet it.

The government has designated June 29 through Sept. 18 as an emergency power supply management period and is maintaining a crisis-response posture with relevant agencies.

Korea Electric Power Corp. has drawn up equipment stability plans covering the three main summer disaster scenarios: heavy rain, typhoons and heat waves. KEPCO has designated the period through Sept. 18 as its summer power supply management period, monitoring power facilities nationwide around the clock and maintaining a standing emergency restoration system capable of immediate deployment through an ICT-based intelligent grid management framework.

"An unusually hot summer is expected amid unprecedented weather anomalies, but ensuring stable power supply is KEPCO's most important mission and we will do our utmost," KEPCO said.