As a cold snap grips the nation, power consumption is increasing rapidly, fueling worries about possible power shortages.

On Wednesday, power demand reached 73.02 million kilowatts, leaving only 4.45 million kW in reserve. The previous day, reserve electricity dropped to 4.11 million kW, barely staying above the 4 million kW mark that triggers emergency measures.

The government’s emergency response manual identifies four stages in emergency management. It enters emergency mode when backup power falls below 4 million kW.

The last stage is when power reserves fall below 1 million kW. It requires the government to implement rolling blackouts ― intentional rotational electricity shutdowns for certain areas to avert a total blackout.

In September last year, the nation suffered rolling blackouts that affected more than 7.5 million households. The reason for the catastrophe was the power authorities’ failure to prepare for an unexpected rise in electricity demand.

This winter, the threat of power outages looms larger than ever for two reasons. First, the meteorological agency has forecast that this winter would be much colder than usual. In November, the average temperature was roughly 4 degrees Celsius lower than a year ago.

According to the Korea Energy Management Corp., power demand rises by 1 million kW when the mercury drops one degree from minus 10 degrees Celsius.

Second, three 1-million-kW reactors at Yeonggwang Nuclear Power Plant are not in operation. Unit 3 was shut down in October after cracks were found in control rod tunnels, while Units 5 and 6 were suspended in November to replace more than 7,000 substandard parts used in them.

According to the Ministry of Knowledge Economy, it would take at least two months to replace the parts.

To make matters worse, the Board of Audit and Inspection announced Wednesday that it has also found that 1,550 substandard parts were used in two reactors at Kori Nuclear Power Plant.

Yet the government said it would not halt the two reactors because the identified parts did not pose a threat to safety. If the two reactors also had to be stopped for parts replacement, the nation would face disaster.

As the mercury is expected to stay below normal for most of the winter, the government estimates that power reserves could drop to 1.27 million kW in January unless intensive power-saving measures are taken.

So it launched an energy conservation campaign on Dec. 3, which would last until the end of February. To avoid another power crisis, citizens and businesses need to actively participate in the campaign.

Citizens are encouraged to save electricity by keeping the temperature in their residences between 18 and 20 degrees Celsius. They also need to refrain from using electricity during the peak hours of between 10 a.m. and noon and between 5-7 p.m.

Companies are required to cut back on energy consumption by 3 to 10 percent, while commercial buildings should ensure that their indoor temperatures do not rise above 20 degrees Celsius.

The government needs to speed up parts replacement for the two Yeonggwang reactors so that they can come back online within this month.