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Countrywide winter power saving period started

Dec. 04, 2012

TOKYO --A power conservation period with no mandatory conservation target began December 3 in all prefectures of Japan except Okinawa. In advance of the start of the period, the Japanese government announced on November 30 the measures to be implemented in the event of tight power supply-demand conditions. When the power supply reserve margin of an electric utility is expected to fall below 3% even with interchange power from other utilities, the government will issue an alert to customers in the utility's service area around 6:00 p.m. on the day before or 8:00 a.m. on the day of a possible scheduled blackout. Then, if the margin is expected to fall even further to below 1%, an emergency alert will be sent to the customers by e-mail.

In the service area of Hokkaido Electric Power Co., Inc., where the possibility of power shortages is especially high, a power conservation period with a target of 7% or more relative to fiscal 2010 will start a week from now on December 10. The utility has been signing contracts for an "emergency adjustment program" with its bulk power customers in hopes of averting scheduled blackouts. Customers who have signed up for this program will be encouraged to stop using electricity except for safety purposes when the utility's supply reserve margin falls below 1%.

The Japanese government will send information to relevant customers in addition to issuing alerts when there is a possibility that Hokkaido Electric Power may put the emergency adjustment program into effect on the following day. If the execution of the program is decided on the day of the execution, the program will take effect at the same time as the government sends out an emergency alert e-mail.

In the event that the power shortage continues after the effectuation of the program, the utility will carry out an emergency negawatt bid, a reverse-auction style system under which Hokkaido Electric Power buys back surplus electricity that customers have saved through their conservation efforts.


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Introduction of The Denki Shimbun, a specialized daily newspaper carrying articles on the electricity and energy industries