By Scott DiSavino
NEW YORK (Reuters) - Demand for electricity in the Midwest power grid is expected to break the region's record later on Tuesday, as homes and businesses crank up air conditioners to escape a brutal heat wave, a spokeswoman for the network operator said.
The hot weather and high demand for electricity to run coolers extends from the Great Plains to the East Coast.
Despite the high demand, all power grids in the Midwest and Northeast said they had enough resources to keep the lights on and the air conditioners humming this week.
In Chicago, temperatures hit 98 degrees Fahrenheit (36.7 Celsius) on Monday and were expected to reach 94 on Tuesday before dropping to near normal levels in the mid 80s on Wednesday, forecaster AccuWeather.com said.
The Midwest Independent Transmission System Operator (MISO), which operates the power grid in all or part of 11 U.S. Midwest states and the province of Manitoba in Canada, forecast demand could reach 99,000 megawatts (MW) on Tuesday, which would break the system's all-time peak of 98,526 MW set in July 2011.
In New York City, high temperatures hit 91 degrees Fahrenheit on Monday and were expected to reach 95 on Tuesday and 96 on Wednesday before falling to near normal levels in the 80s on Thursday, according to AccuWeather.com.
New York power company Consolidated Edison, which locked out its 8,000-member union workforce on July 1 due to a contract dispute, said it had ended a voltage reduction in some Manhattan neighborhoods late on Monday.
Con Edison continued to ask its 3.2 million customers in the New York metropolitan area to conserve power during the heat wave.
Con Edison said on Tuesday its system was working fine and only 97 customers were without power, which is low for a utility of its size at any time of year.
Other power grids in the Northeast and Midwest forecast high demand on Tuesday and Wednesday but not at record-breaking levels.
One megawatt can power about 1,000 homes.
To take some stress off the grids, the operators have asked generators and transmission owners to put off unnecessary maintenance.
MIDWEST LOOKING FOR POWER
In the Midwest, MISO also asked generators in neighboring grids to sell power into the MISO system.
Earlier this month, when generators outside MISO sold power into the Midwest grid, real-time power prices jumped sharply, briefly exceeding $1,000 per megawatt-hour.
By Tuesday afternoon, however, real-time prices in the major MISO hubs were mostly between $50 and $200.
The New York ISO, which operates the grid in the state, urged customers who participate in demand response programs to reduce power usage.
Earlier this summer, the New York ISO said it had over 1,000 MW of power reductions from its demand response programs.
ISO New England and PJM, the biggest U.S. power grid serving over 60 million people in all or parts of 13 Mid-Atlantic and Midwest states and the District of Columbia, said they had not yet activated their demand response programs and were not planning to do so during this heat wave.
Demand response programs pay consumers to cut electric use during peak times or when power prices are high by shutting off unnecessary lights, elevators and other equipment, reducing air-conditioning and even turning on backup generators to reduce the amount of power they take from the grid.
The biggest power companies in the regions baking in the latest heat wave include units of Duke Energy, Exelon Corp, FirstEnergy Corp, American Electric Power Co Inc, Xcel Energy Inc, Con Edison, National Grid PLC and Northeast Utilities.
(Reporting by Scott DiSavino; Editing by David Gregorio and Dale Hudson)