By Scott DiSavino
(Reuters) - U.S. power prices rose to their highest in months in a couple of markets as homes and businesses cranked up their air conditioners to escape a brutal heatwave blanketing much of the country this week, stressing electric grids.
Extreme weather reminds consumers of the fatal freeze in February 2021 that left millions of Texans without power, water and heat for days and a brutal heatwave in August 2020 that forced the California grid operator to impose rotating outages for a couple of day that affected around 800,000 customers.
In the spot market, next-day power for Thursday jumped to their highest since December 2022 at the Palo Verde hub in Arizona and the highest since February at the PJM Western Hub, which covers an area from northwestern Pennsylvania to Washington, D.C.
AccuWeather meteorologists forecast temperatures would reach the 90s Fahrenheit (35 Celsius) in New York, Los Angeles, Chicago and Houston over the next few days and over 110 F in Phoenix.
That compares with normal highs of 85 F in New York, 83 in Los Angeles, 85 in Chicago, 95 in Houston and 106 in Phoenix.
Grid operators across the country declared hot weather alerts this week and told energy companies to put off unnecessary maintenance so all available generating plants and power lines would ready for service.
The California Independent System Operator (ISO) issued an energy emergency alert for Wednesday night, the third in a week, "due to some resources going offline, continued excessive heat in interior Southern California, and transmission congestion restricting movement of power to parts of the state where it’s needed."
Despite the extreme heat, grid operators do not expect power use to break all-time highs this week. The Texas grid operator, however, does expect demand to set new records next week as the heatwave lingers.
After setting 11 demand records last summer, the Electric Reliability Council of Texas (ERCOT), forecast usage would hit 83,402 megawatts (MW) on July 31 and 84,386 MW on August 1. That would be the sixth and seventh record highs this summer and would break the current all-time high of 82,592 MW set on July 18.
One megawatt can power around 1,000 U.S. homes on a typical day, but only about 200 homes on a hot summer day in Texas.