PJM Interconnection Issues Capacity Advisory for Oct. 19

PJM Interconnection issued an electric power capacity advisory for October 19, 2026, warning that about 72,000 megawatts of generation and transmission facilities will be unavailable due to maintenance and construction outages, leaving roughly 60% of total generation capacity available to meet an estimated peak load of 94,573 megawatts across its 13-state footprint and Washington, D.C., paenvironmentdaily.blogspot.com reported. Expected generation capacity availability is about 110,000 MW against a total generation capacity of about 182,000 MW.

Grid Operations Face Maintenance Strains and Weather Pressures

The October 19 advisory follows an unseasonably warm fall week that triggered a maximum generation alert from October 13 through October 14. During that earlier alert, PJM operated with only 66% of its generation capacity available, as roughly 61,000 megawatts of power generation went offline due to a mix of planned maintenance and unexpected outages. Of those offline megawatts, approximately 15,000 megawatts stemmed from unexpected power plant failures.

The grid operator notes that mid-September through early December is the traditional shoulder season when transmission and generation facilities undergo scheduled maintenance to prepare for peak winter heating demands. However, consumption from data centers and other energy-intensive large-load customers remains constant around the clock throughout the year. These facilities do not experience seasonal demand drops, creating system stress during periods traditionally reserved for grid upkeep. In a statement on October 15, PJM said, Most of the new, rapidly growing energy demand is from data centers and other energy-intensive Large Load customers, and their consumption does not fluctuate significantly with the weather; it is a 12-month 24/7 phenomenon. PJM also stated, The result is that periods the grid once relied on for maintenance and preparation can now become periods of significant system stress and reliability risk.

PJM Uses Capacity Advisories to Manage Power Shortfalls

The capacity advisory itself is a new emergency procedure endorsed by PJM members in June to signal approaching capacity shortfalls before they escalate into critical emergencies. Under this advisory, PJM holds the authority to recall or reschedule generation outages, call generation out of market, recall transmission outages to boost deliverability, and notify neighboring regions to expect reduced power imports.

Data center expansion continues to reshape regional energy planning. Pennsylvania regulators and developers face overlapping pressures regarding grid reliability and infrastructure costs. State officials and public utilities are actively evaluating the siting of new generation assets and transmission lines, including proposals involving natural gas power plants and nuclear facilities to satisfy rising computational power demands.