Some industries in Shanghai, the country's financial hub, have been forced to shift their hours of operation to reduce power consumption during peak times.

About 700 local enterprises have been affected in this latest in a string of moves the city has taken to ensure the local power supply this summer. Another heat wave started last weekend.

The 700 affected enterprises, all big energy consumers, were asked to shift operations temporarily to the graveyard shift, midnight to 8:00 AM.

The period the policy is to stay in effect is unknown, officials said.

Home to more than 16 million people, Shanghai reported on Sunday the hottest day of the summer as the temperature hit more than 37 degrees Celsius.

The city is facing a power supply gap of 2.0 million to 2.6 million kilowatts this summer, said Zhang Hongtao, publicity official of the Shanghai Municipal Economic Commission (SMEC).

Earlier, another 500 local enterprises were asked to make similar adjustments to their operating hours.

The involved enterprises are small ones operating in energy-consuming sectors such as steel refining, cement or iron alloy manufacturing. Officials said changes to production times would not affect the city's overall economic performance.

The time shift will cut up to 500,000 kilowatts from power demand, said He Changqun, SMEC's power department director.

"We have had good contact with the enterprises. . . . the key issue now is to what extent they will carry out the move," said He.

Although he declined to reveal further specifics about the enterprises, He said foreign-invested businesses on the whole are not included because their operations and advanced technologies are more energy efficient. There are, however, a few exceptions.

Meanwhile, other enterprises are expected to halt production on a weekly basis, while work at a number of local construction sites in non-essential industrial or infrastructure projects is supposed to stop whenever the temperature exceeds 35 degrees Celsius.

The city also plans to adopt variable-rate electricity charges. Local government offices and large retail facilities are expected to keep air conditioners no lower than 26 degrees Celsius to save power. Many local decorative lamps will be shut off during peak-use periods.

"We are basically ready for the power demand this summer, but we are afraid that the number of high-temperature days may exceed forecasts," said Zhang.

The State Power Grid Company has said that the entire country may be facing its most severe power shortage since the 1980s, with a gap of 30 million kilowatts between electricity demand and supply this summer. Twenty-four provincial areas have imposed power brownouts in the past few months.

On July 6, some 6,000 companies in Beijing shifted their operating hours away from peak-use periods.

(China Daily July 13, 2004)