Japan's Aichi partially resumes supplying industrial water to coal-fired power plants

Japan's Aichi prefecture partially resumed supplying industrial water to JERA's 4.1 GW Hekinan coal-fired power plant and other coal-fired power plants in the central Nagoya region on May 19 following a suspension on May 18.

JERA's Hekinan thermal power station started receiving industrial water from about 7 pm local time on May 19. The power station started accepting water into its storage tank from about 9 am on May 20 due to stable water quality, according to a statement from Japan's largest power generation company.

"Since the current amount of industrial water received is less than the amount required for operation at the maximum output of the Hekinan thermal power plant, the total output of the Hekinan thermal power plant will continue to be reduced to about half to reduce the use of industrial water", a JERA spokesperson said. JERA will consider the future operation status based on the amount of industrial water received and restoration time outlook.

The suspension of industrial water supply in Aichi on May 18 led to unplanned shutdowns of 249 MW of coal-fired capacity in the Nagoya area, reducing output at the Hekinan thermal power plant amid Japan's off-peak power demand season.

Supply was suspended on May 18 because of a malfunction at water intake works.

Market participants were keen to find out how long the outages may last and its potential impact on alternative power generation units, such as LNG-fired power generation units, although it is not peak demand season.

Nakayama Nagoya Joint Power Generation, in which Osaka Gas has a 95% stake via a wholly owned subsidiary, shut the 149 MW No. 1 coal-fired unit at its Nagoya power plant and the 110 MW No. 1 coal-fired unit at its Nagoya Daini power plant on May 18.

An Osaka Gas spokesperson said on May 20 the Nakayama Nagoya Joint Power Generation Daiichi, or Unit 1, with a total output capacity of 149 MW, began receiving industrial water supply at 7 pm on May 19. About seven hours later, Unit 1 started sending electricity to the grid at 2 am on May 20, and is currently at full production capacity, according to the spokesperson.

Meanwhile, Daini, or Unit 2, with a capacity of 110 MW, has also received water supply, and has started supplying electricity for power transmission at 6:20 pm on May 20. "We are planning to gradually ramp up output, as the supply of water quality is stable. However, we still can't predict the volume of water supply so we don't know how much we can ramp up output," the Osaka Gas spokesperson said.