Restart Pushed Back for Unit at Quake-Hit Hokkaido Power Plant

September 24, 2018

Sapporo- Hokkaido Electric Power Co. said Sunday that it has decided to postpone the restart of the No. 2 unit at its quake-hit Tomato-Atsuma thermal power station to mid-October, because of a problem with some equipment.

The company said its power supply capacity is currently well above demand, while asking customers to make reasonable efforts to cut electricity consumption.

Boiler tubes of the 600,000-kilowatt No. 2 unit at the largest thermal power plant in Hokkaido were damaged due to the 6.7-magnitude earthquake that rocked the northernmost Japan prefecture on Sept. 6.

Shortly after the quake, the regional power supplier said that the unit would be brought back online in mid-October or later.

On Thursday, the company said that the generator can be reactivated as early as Sunday as work to replace boiler tubes had been completed.

Hokkaido Electric said on Sunday, however, that it found a problem with part of a device for crushing coal to raise combustion efficiency during test operations of the No. 2 unit.

The device was partially suspended at 3 p.m. Saturday (6 a.m. GMT), company officials said, adding that it will take about three weeks to finish inspections and cleaning work.

According to the firm's announcement on Sunday, the day's estimated peak electricity demand stood at 3.23 million kilowatts. Meanwhile, its peak capacity was forecast at 3.98 million kilowatts, some 23 pct above the peak demand level.

The margin is far higher than 3 pct, which is regarded as the minimum necessary level to ensure stable electricity supply.

All three units at the Tomato-Atsuma plant, located in the Hokkaido town of Atsuma, were halted after the temblor, which measured the highest level of 7 on the Japanese seismic intensity scale in the town.

The 350,000-kilowatt No. 1 unit was restarted on Wednesday. The 700,000-kilowatt No. 4 unit is expected to go back into operations in November or later. Jiji Press