The government officially decided Tuesday to ask households and businesses across Japan to save electricity this winter following a similar request in summer amid lingering power crunch concerns.

What will be the first electricity-saving request for winter in seven years will kick in from Dec. 1 through the end of March as the supply of liquefied natural gas used to fuel thermal power plants remains uncertain due to market disruptions stemming from Russia's invasion of Ukraine.

Economy, Trade and Industry Minister Yasutoshi Nishimura arrives at the prime minister's office in Tokyo on Nov. 1, 2022. (Kyodo)

Japan is expected to secure a reserve power supply capacity rate of 3 percent, the minimum level deemed necessary to provide stable supply, for the winter season, but the government wants to make sure that there will be enough power to heat homes and maintain businesses even if natural disasters or glitches hit power plants.

"As part of measures to ensure (stable) supply, we decided to resume the operation of off-line power plants and purchase additional fuel, among other things," Economy, Trade and Industry Minister Yasutoshi Nishimura told reporters.

During the power-saving period, people will be asked to wear more clothes indoors, set air conditioners to lower temperatures and turn off lights when not needed.

The government plans to award points to households that cut monthly electricity consumption by 3 percent or more compared with the previous year, in coordination with utilities' reward point systems.

The electricity supply and demand balance is expected to be tightest in January, during which reserve supply capacity is projected at 4.1 percent in eastern and northeastern Japan areas serviced by Tokyo Electric Power Company Holdings Inc. and Tohoku Electric Power Co.

In central to southwestern Japan, areas serviced by Chubu Electric Power Co., Hokuriku Electric Power Co., Kansai Electric Power Co., Chugoku Electric Power Co., Shikoku Electric Power Co. and Kyushu Electric Power Co., the Ministry of Economy, Trade and Industry said it expects the reserve rate to be 5.6 percent.

The reserve rates in northern and southern Japan areas serviced by Hokkaido Electric Power Co. and Okinawa Electric Power Co. are expected to be 7 percent or higher.

Electricity supply in Japan has declined as major utilities have halted or scrapped aged thermal power plants as part of cost-cutting efforts. The government is asking them to reactivate idle plants.

The ministry has also said it intends to speed up efforts to restart nuclear reactors that meet stringent safety standards, implemented after the 2011 nuclear disaster triggered by a massive earthquake and tsunami in northeastern Japan, as another way to ensure stable power supply.

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