Power grid operators across the eastern United States have spent much of this summer warning that extreme heat is tightening electricity supplies faster than reserve margins can comfortably absorb. The latest concern centered on PJM Interconnection, which manages the nation’s largest grid across 13 states and the District of Columbia, where emergency procedures were activated as demand climbed toward seasonal peaks.
PJM moved to emergency procedures as demand surged
PJM Interconnection, the regional grid operator for all or parts of 13 states and Washington, D.C., formally requested a federal emergency order on June 27, 2026, saying it might need extra backup generation during a forecasted heat wave expected to run from June 29 through July 3. In that filing to the U.S. Department of Energy, PJM said peak demand for July 2 could reach about 162,860 megawatts, a level high enough to strain normal operating reserves.
PJM stated in the filing that it was using every reliability tool available before any interruption of firm customer load. The grid operator said it had already recalled some maintenance outages and issued emergency notices tied to resource adequacy and transmission constraints, especially in the Baltimore Gas and Electric, Pepco, and Dominion zones. PJM also said its system serves more than 67 million customers, making the alert significant well beyond any single utility territory.
The emergency framework matters because Energy Emergency Alert levels are staged. PJM’s own emergency procedures show that EEA 1 and EEA 2 are escalating warnings used before manual load dumps under EEA 3, the level associated with controlled outages. That is why the situation was widely described as one step away from rolling blackouts, even though PJM said at the time that firm customer interruptions remained a last resort.
The states inside PJM’s footprint are Delaware, Illinois, Indiana, Kentucky, Maryland, Michigan, New Jersey, North Carolina, Ohio, Pennsylvania, Tennessee, Virginia and West Virginia, along with the District of Columbia, according to PJM’s territory map. Because PJM operates only in parts of several of those states, the exact number of households or businesses at greatest risk was not broken out publicly in the emergency filing.
That gap is important for local residents. PJM did not release a comprehensive public list of neighborhoods, municipalities or utility service areas that would be first in line for any controlled outages if conditions worsened. The filing instead described broader operating zones where constraints were a concern, particularly the BGE, PEPCO and Dominion areas, which include major population centers in Maryland, the District of Columbia and parts of Virginia.
The “17 states” figure circulating in coverage appears to combine PJM’s multistate territory with neighboring regional impacts and emergency notices elsewhere, but PJM itself identified 13 states and the District of Columbia in its official materials. What is confirmed is that the alert covered a very large share of the Mid-Atlantic and Midwest power market, and that millions of residents were inside the grid region under emergency procedures.
PJM has been warning for months that electricity demand is growing faster than new dispatchable supply is being added. In its winter outlook and annual market reporting, PJM said reserve margins are tightening as load growth outpaces new generation, even though some new resources continue to come online. The operator has also pointed to generator outages and transmission limits as factors that can magnify stress during extreme weather.
In the June 27 emergency request, PJM tied the immediate risk directly to temperatures in the 90s and above 100 degrees in some zones, combined with capacity deficiencies and import constraints into high-demand areas. On July 3, PJM later said preliminary figures showed peak instantaneous load on July 2 reached about 162,700 megawatts, though demand response programs helped suppress the total. PJM also said that particular alert did not require action from customers.
For residents, the practical takeaway is that emergency alerts do not automatically mean blackouts, but they do indicate the grid operator is exhausting additional reliability measures to avoid them. PJM said it would continue coordinating with generators and transmission owners and use demand response, deferred maintenance and federally authorized backup generation relief before considering firm load interruption, leaving the final outcome dependent on weather, equipment performance and real-time electricity use.