BETHLEHEM, Pa. — As a powerful heat wave grips the region, electricity demand across Pennsylvania and neighboring states could surge to levels not seen in more than a decade.
PJM Interconnection, the regional grid operator headquartered in Valley Forge, issued a maximum generation alert and load management alert for Monday.
PJM, which covers parts of 13 states from the Midwest to the Mid-Atlantic, said demand could top 160,000 MW Monday afternoon — potentially the highest usage since July 2011.
The company’s record summer peak is 165,563 MW, set in 2006.
PJM said the alert means that conditions may require all generators to operate at their maximum output capability, but does not require any action from customers.
PJM has issued a Maximum Generation Alert and Load Management Alert for June 23 as hot weather continues throughout the region PJM serves to ensure the reliable delivery of electricity to its customers across 13 states and D.C. This alert does not require any action from… pic.twitter.com/WYsrN36c7L
— PJM Interconnection (@pjminterconnect) June 22, 2025
'No transmission lines or facilities are overloaded'
With hot, humid weather expected to linger through the week, PJM and local utilities are urging residents and businesses to conserve energy, especially during peak afternoon hours, to avoid strain on the grid and reduce the risk of any outages.
PJM said it has 179,200 MW of generation capacity this summer, as well as 7,900 MW of contracted demand response.
Demand response programs pay customers in advance to have their electricity use automatically reduced in times of system stress.
PJM said its team of operators already have prepared for multiple scenarios in which the grid could be impacted by weather, emergency conditions or equipment failure.
The team works to “adjust resource output with changes in demand and ensure that no transmission lines or facilities are overloaded.
"The team also watches for unusual conditions and reacts to them to protect the electricity supply,” PJM said on its website.
Beat the heat
The Pennsylvania Public Utility Commission said simple steps can make a big difference in staying safe and comfortable during this oppressive stretch, even with limited use of air conditioning.
The PUC advises customers to:
- Use fans to create airflow that can help you feel several degrees cooler without lowering your thermostat. Ceiling fans should rotate counterclockwise to create a cooling downdraft
- Follow the shade and spend time in rooms that stay cooler and avoid direct sunlight
- Block the heat by using curtains or blinds during the sunniest hours to reduce indoor temperatures
- Delay use of stoves, dryers and dishwashers until cooler hours to avoid generating unneeded heat
- Use outdoor grills or microwaves instead of ovens to reduce indoor heat buildup.
The National Weather Service said Monday and Tuesday will be the warmest days of the week, with gradual improvement later in the week and returning chances for showers and thunderstorms.
