Soaring Temperatures Stress US Grids

Blistering heat is straining power grids across the eastern half of the US, leading to a blackout in part of New York City’s borough of Queens as the local utility issued a warning to conserve electricity.

Consolidated Edison Inc. is working to restore service to more than 6,200 customers in southeast Queens, the company said in a statement. The utility asked residents in the area not to use energy-intensive appliances like washers and microwaves until crews complete repairs.

ConEd has also reduced voltage in Brooklyn and Staten Island to perform repairs, asking more than 168,000 customers in both areas to conserve, including limiting unnecessary use of air conditioners and refraining from charging electric vehicles.

Two regional grids serving 110 million people from the Great Plains to the mid-Atlantic have also issued level-one energy emergency alerts — the lowest level — for Monday as intensifying heat drives up air conditioning needs, straining power supplies.

PJM Interconnection, which operates the 13-state system from Illinois to Washington, DC, expects demand to climb to nearly 160.2 gigawatts, which would be the highest peak since July 2011, before topping that on Tuesday. The Midcontinent Independent System Operator also declared a maximum generation event for the Midwest and central states it serves, requiring all supplies to be on hand from 4 p.m. to 10 p.m. Eastern.

The temperature in New York’s Central Park reached 96F (36C) on Monday, according to the US National Weather Service. Excessive-heat warnings are in effect along the US East Coast as well as an area from eastern Texas and Kansas to southern Maine.

Homes and businesses across New York state and down to Virginia have been asked to curtail demand Monday afternoon if they are enrolled in programs to help avoid an outright power emergency, according to grid notices.

Photo: Photographer: Yuki Iwamura/Bloomberg