Over the past two weeks, three separate fires - one in Manhattan and two at the same power station in Queens - briefly pitched thousands of New Yorkers into the dark and raised a general unease among residents about the system's reliability.

These latest mishaps could not have come at a worse time.

With temperatures soaring and air conditioners putting an extra heavy strain on the grid, the system's equipment is especially vulnerable, despite millions of dollars invested by local utilities to shore up the grid. These latest outages, accompanied by public pleas to save energy, have left New Yorkers wondering aloud whether elevators and subways might leave them stranded or whether they will have air conditioning when they get home.

They also raise serious questions about whether New York risks becoming the next California, where a botched electric industry deregulation plan and a woeful lack of new power plants triggered a series of rolling blackouts in early 2001.

"We need more power plants built in the city and we need to keep improving our distribution system.

Upgrading the infrastructure is a job that is never complete," said Mike Clendenin of Consolidated Edison Inc. ((ED.N)), which serves some 9 million people in the New York metropolitan area.

Con Edison has spent $533 million this year on its electric distribution system as part of a five-year $3.2 billion program to enhance reliability and improve infrastructure.

Federal regulators have raised warning flags about the power grid in New York and its neighboring suburbs on Long Island and Connecticut.

Power supplies in New York City area are some of the tightest in the nation because construction of power plants and transmission lines has not kept up with the region's economic and population growth. The Business Council of New York, a commercial trade group, warns that New York State needs another 9,200 megawatts of power - the equivalent of nine huge power plants - over the next five years if it is to keep pace with projected growth.

"New York City and Long Island have serious transmission problems. We need to focus on building more plants and upgrading the transmission system," said Gavin Donohue of the Independent Power Producers of New York, an industry trade group representing the state's power producers.

Donohue suggested New York officials could help by streamlining the power plant approval process and using tax dollars to help Con Ed bolster the transmission system rather than using state agencies to install more power plants.

Last summer, the state-owned New York Power Authority (NYPA) spent hundreds of millions of dollars to install 11 small, natural gas-powered turbines at sites throughout New York City and Long Island to add about 450 megawatts of generating capacity -- enough for about 450,000 homes. "We need to put more incentives in place for utilities to upgrade the transmission systems. The state can help by using its power authorities -- NYPA and the Long Island Power Authority -- to rebuild transmission networks," Donohue said.

Until more plants are built and transmission lines are upgraded, New Yorkers will continue to fret over the reliability of the grid, especially on those days when the heat and humidity push power demand to the brink of what the system can supply.