Shanghai will encourage government officials to dress less formally this summer to reduce power consumption from air-conditioners, a city official said yesterday.

"Government officials should take the lead of less formal dress in indoor workplaces," Zhou Minhao, a spokesperson of the Shanghai Economics Commission, said yesterday in a municipal news conference.

According to the city's meteorologists, the number of days above 35 degrees Celsius will reach 24 to 30 this summer from June 15 to September 23.

The power load this summer is expected to exceed 23 million kilowatts, up 10 percent from last summer, Zhou said.

"We are about to encounter a power shortage," Zhou said.

He said the government would take temporary measures to control the power supply for industrial uses.

The government will require some factories to rearrange work hours; some pollution-causing industries will be suspended; and electricity fees for industrial use will be adjusted.

"We will try our best to ensure a sustainable power supply for residential use," he said.