Anticipating power shortages due to its closed quake-hit nuclear plant and a surge in air conditioner use during the current heat wave, Tokyo Electric Power Co. said Wednesday that it had resorted to emergency supply-adjustment measures for the first time in 17 years.

Tokyo Electric said it expects to save between 150,000 and 200,000 kw by reducing the power specifically to 23 large-lot industrial customers between 1 and 5 p.m.

Under the terms of its contracts with 1,250 large-lot customers, including factories and offices, Tepco can temporarily curb the power supply when it cannot meet demand.

This is the first time Tepco has resorted to such an emergency supply-adjustment measure since 1990, when electricity demand was high during the bubble economy era.

The utility also received government permission to temporarily use its 900,000-kw Shiobara hydroelectric plant in Tochigi Prefecture as an emergency measure.

The plant was shut down after it was discovered Tepco had violated the River Law regarding water intake for power generation.

Power demand grew this week as factories and offices resumed operations after the Bon holiday.

Tepco said electricity consumption reached 61.47 million kw between 2 and 3 p.m. Wednesday in Tokyo and eight other neighboring prefectures.

The utility also said it raised output capacity to 64 million kw Wednesday, exceeding Tuesday's 62.3 million kw. On Tuesday, Tepco supplied 60.13 million kw of power, marking the highest amount this year.

Following the announcement by Tepco, the Ministry of Economy, Trade and Industry issued a statement asking consumers to save power, noting the power company expects the supply to be extremely tight.

Meanwhile, the ministry turned off lights in lobbies and corridors and turned up the thermostat in its buildings. It also said it called on other government ministries and agencies to join in the effort to save energy.

Tepco indefinitely shut its seven-reactor Kashiwazaki-Kariwa nuclear plant in Niigata Prefecture due to radiation leaks and a fire following an earthquake in July.

Also Wednesday, the Federation of Electric Power Companies of Japan said the country's 10 power companies supplied 3.42 billion kw of power Tuesday, a record high amount for a single day.

Information from Kyodo added