As winter approaches, the specter of blackouts looms again. On Sept. 15, Korea suffered rolling blackouts. The cause of the disaster was heavy use of air conditioning due to an unseasonable heat wave. A sudden spike in power demand overshot the nation’s supply capacity, forcing the grid operator to cut electricity supply to avert a total blackout.

The chances of such a disaster taking place in winter are greater than in summer with the widespread use of electrical heating appliances. According to a forecast presented by the Ministry of Knowledge Economy, peak power demand is expected to increase 7.4 percent this winter compared with a year ago, while the nation’s power generation capacity is projected to grow a mere 2.4 percent, narrowing the already tight margin between power demand and supply.

To ensure a stable power supply, the grid operator needs to keep power reserves above 5 percent of its 79 million kilowatt power generation capacity, about 4 million kilowatts. But power reserves are likely to remain below that level during most of the winter. In particular, the ministry warned that reserves could fall to as low as 530,000 kilowatts during the peak period, which generally comes in the middle of January.

To avoid another disaster, the ministry has come up with a package of measures. Among other things, it intends to require the nation’s 14,000 largest power-consuming companies to cut power use by 10 percent from a year earlier during the peak hours ― from 10 a.m. to noon and from 5 p.m. to 7 p.m. ― between Dec. 5 and Feb. 29. During the mid-January peak season, they will be required to cut power consumption by 20 percent.

In addition, the plan will require some 47,000 commercial and educational buildings throughout the nation to maintain their indoor temperatures at below 20 degrees Celsius. For the 19,000 central and regional government offices, the maximum temperature is set at 18 degrees Celsius. Some 2,600 general-purpose buildings will be told to turn off their heating systems for 30 minutes during peak hours each day.

The ministry will also order service-sector establishments to switch off their neon signs ― estimated to number 220,000 ― from 5 p.m. to 7 p.m. each day throughout the winter. They will only be allowed to use one neon sign during the remainder of the day.

The ministry hopes this package, which includes other measures, will enable the grid operator to maintain power reserves above 4 million kilowatts. Yet it is highly questionable if the ministry can implement it, as some of the measures sound impractical.

In the first place, many manufacturers may ignore the required 10 percent power consumption cut during peak hours as it could affect production. During the Sept. 15 crisis, many companies did not reduce their power use to the level they had agreed to in an emergency. Violating companies will face fines of up to 3 million won, but this penalty is nothing more than a slap on the wrist for many of them.

Furthermore, it would be almost impossible to monitor the 47,000 buildings subject to the planned indoor temperature regulation. The maximum fine for the nonconforming buildings is also 3 million won, which is too small to have an impact.

For these reasons, President Lee Myung-bak called for a more “realistic and workable” plan when briefed on the ministry’s scheme on Thursday. He was right to emphasize the need to design the power-saving plan in a way that can elicit voluntary cooperation from corporations. The ministry needs to learn how Japan has successfully overcome a severe power shortage following the Fukushima nuclear disaster.

Yet the most effective way to curb power demand is to raise electricity rates, which average just 94 percent of the generation costs, especially those for large corporations with excessive power consumption.

The government needs to strengthen demand control efforts for some years as the nation cannot expect a significant boost in generation capacity until 2015. The general public needs to participate in the power conservation campaign and break their old wasteful habits.