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Sydney turns lights out for conservation

Environmental show lasts 1 hour

The difference in Sydney's skyline after switching off many nonessential lights is shown in this combination photograph taken a week before and during the blackout. (Paul Miller/Associated Press)

SYDNEY -- Australia's largest city plunged itself into near darkness for an hour last night when city officials, thousands of businesses, and many more residents cut the lights for energy conservation.

The normally gleaming white sails of the Sydney Opera House darkened, as did the arch of the city's iconic harbor bridge, big chunks of the downtown skyline, and countless homes in the city of 4 million in a gesture of concern about global warming.

"Tonight is a call to action," said Mayor Clover Moore, whose officials shut down all nonessential lights on city-owned buildings. "We all have to act to reduce our ecological footprint. We are asking people to think about what action they can take to fight global warming."

Restaurants throughout the city held candlelight-only dinners, and families gathered in public places to take part in a countdown to lights out, sending up a cheer when the lights started going out at 7:30 .

There was no master switch, though, and it took a few minutes for the effect to take hold; buildings went dark at slightly different times. Some floors in city skyscrapers remained lighted, and security and street lights, lights at commercial port operations and at a sports stadium stayed on.

While downtown was significantly darker than normal, the overall effect, as seen in television footage from helicopters, was that the city's patchwork of millions of tiny lights had thinned, not disappeared.

"We were expecting a big difference straight away, but it was just a little bit," said Sonja Schollen, who took her sons to a park to watch the skyline. "It was quite sweet, actually, because the kids started chanting: 'Turn them out. Turn them out.' You can see now the city's a bit dimmer."

Children waved glowing sticks and sparklers while parents picnicked and sipped wine.

Organizers hope yesterday's event -- which about 2,000 businesses and more than 60,000 individuals signed up for online -- will get people to think about regularly switching off nonessential lights, powering down computers, and other simple measures they say could cut Sydney's greenhouse gas emissions by 5 percent in the next year.

Research by the University of New South Wales published last week found Sydney residents are poor at energy conservation, often leaving heaters and air conditioners running in empty rooms.