The recent cold snap has driven up energy consumption in the country, prompting the authorities to issue a warning after the reserve power level fell sharply this week.

The Korea Power Exchange said electricity consumption surged on Wednesday, causing the reserve to fall below the 4 million kw safety zone. A stepped-up alert is issued when it dips under 3 million kw.

The agency urged the public to conserve power to avoid a power crunch. Starting next month, it plans to make it mandatory for big companies to gradually cut their energy consumption by 3 to 10 percent per month.