PJM Interconnection activated demand response resources and secured an emergency order from the US Department of Energy as unusually warm September weather and 36 gigawatts of outages tightened power-system reserves, according to a statement on Thursday.
The DOE order, secured amid the heat and in effect through Friday, eases some plant restrictions and permits backup power use at large-load sites, including data centers.
PJM issued Pre-Emergency and Emergency Demand Response for customers across its footprint Thursday afternoon to strengthen reserves ahead of the evening peak.
The programs compensate customers in advance for agreeing to reduce electricity use when PJM calls on them, providing operators with additional flexibility during periods of higher demand.
A Maximum Generation or Load Management Alert also remained active across PJM, allowing generation and transmission owners to defer or cancel maintenance or testing where possible, the grid operator said.
The alert also warns neighboring systems that PJM may curtail electricity exports.
Above-normal temperatures across much of PJM pushed the forecast peak load to about 132 GW as of noon Thursday.
Hotter weather also increased electricity demand and export needs to neighboring regions to the south and west, where temperatures were even higher.
PJM is in its annual outage season, when transmission and generation operators typically conduct maintenance and construction from mid-September through December ahead of extreme-weather demand, PJM Inside Lines said.
PJM pulled back some planned generation and transmission outages, but roughly 36 GW of generation capacity remained offline, along with transmission outages, the grid operator said.