Govt calls for power saving to avert crunch

The Yomiuri Shimbun
One person uses a parasol as others walk in the shade of trees in Chiyoda Ward, Tokyo, on Wednesday.
The Yomiuri Shimbun
People wait at a traffic light under the shade of trees in Chiyoda Ward, Tokyo, on Wednesday.

The Economy, Trade and Industry Ministry on Wednesday maintained its power crunch warning for the area served by Tokyo Electric Power Company Holdings, Inc., and decided to continue it Thursday.

Due to severe heat, electricity demand on Wednesday was expected to be close to the summer peak, and the ministry called for power saving between 3 p.m. and 8 p.m. to a reasonable extent.

According to TEPCO Power Grid Inc., the preliminary power consumption rate from 9 a.m. to 10 a.m. on Wednesday was 95% as of 10:50 a.m. During the peak demand period, from 4 p.m. to 5 p.m., it was expected to hit 97%.

The No. 5 unit at JERA Co.’s Anegasaki gas-fueled thermal power station in Ichihara, Chiba Prefecture, was scheduled to go online on Wednesday, but repair work took time and the start of operations was put off to Thursday. This made for a tight balance of supply and demand for Wednesday. JERA was jointly established by TEPCO and Chubu Electric Power Co., and the No. 5 unit has an output capacity of 600 megawatts.

In summer, supply and demand tend to be tight in the evening. In the evening, as the amount of electricity from solar power decreases, factories and other facilities continue to operate, while household electricity use also rises.

The reserve margin, which indicates how much excess capacity there is in electricity supply, was expected to be 2.6% between 4:30 p.m. and 5 p.m., as of 10:10 a.m. The ministry issues an alert, which is stronger than a warning, for the next day calling for power conservation if the reserve margin falls below 3% at 4 p.m.

Although the reserve margin on Wednesday was expected to fall below 3%, an economy ministry official said: “The supply-demand balance changes from moment to moment. We will make a decision on whether to issue an alert while keeping an eye on the overall supply-demand situation.”