A dangerous heat wave battering the mid-Atlantic region is pushing the PJM Interconnection power grid toward a historic breaking point, with Thursday's load forecast to exceed 165,563 MW — the summer hourly integrated record set in 2006. The U.S. Department of Energy issued an emergency order on Tuesday directing PJM to maximize generation output, including firing up fossil fuel plants and, if necessary, curtailing data centers and other large loads with backup generation. The order comes as dangerous heat indices reach up to 115 degrees across most of the central and eastern U.S. through the Independence Day weekend.
The emergency extends well beyond PJM's territory. The New York Independent System Operator expects Thursday's peak to hit 32,410 MW, while ISO New England projects 25,850 MW of peak load around 7 p.m. Thursday. Con Edison asked customers to "limit use of multiple A/Cs and large appliances between 2 and 10 p.m. during the heat wave." The Midcontinent Independent System Operator issued a conservative operations declaration on Tuesday. By Tuesday night, AccuWeather reported 167,000 outages across the U.S., with warnings that the combination of extreme heat, surging air conditioning demand, and thunderstorms could push totals higher.
Energy Secretary Chris Wright wrote in DOE's emergency order that "given the emergency caused by the expected load stress, additional dispatch of the Specified Resources is necessary to best meet the emergency and serve the public interest." Those specified resources are all fossil fuel plants, including many dual natural gas and fuel oil plants. The order also approved PJM's request to "direct transmission owners, if required as a last resort prior to voltage reduction or load shed, to curtail data centers and other large loads that have backup generation." Wright acknowledged that "the additional generation may result in conflict with environmental standards and requirements," but authorized it under emergency conditions.
The crisis reveals what the order calls "tens of gigawatts of readily available backup generation that have remained largely untapped," particularly at data centers — including hyperscaler facilities — and other large load sites. PJM had already taken preventive steps, issuing a recall on June 25 for all maintenance outages to be returned to service to increase available generation. The grid operator's request to DOE emphasized that transmission owners should work with electric distribution companies to help large customers bring backup resources online, including by disconnecting them from utility power sources. ISO New England warned it's "expecting exceptionally tight operating conditions on the regional electric grid" during Thursday's peak.
The extreme heat is expected to bring near-record or possibly record energy usage to mid-Atlantic power providers, with AccuWeather Senior Meteorologist Alan Reppert calling Thursday "especially critical" as some companies could see power cuts to stabilize the grid if it becomes unstable. The National Weather Service said dangerous, record-breaking heat will continue across most of the central and eastern U.S. through Friday, then focus on the eastern U.S. through the Independence Day weekend, with peak heat indices up to 115 degrees and numerous daily temperature records possible. If PJM's load breaks the 2006 record on Thursday, it will mark the first time in 20 years that the summer peak has been exceeded — a milestone that underscores how climate-driven heat waves are testing grid infrastructure built for a different era.