Breaking: Warm Weather and Maintenance Outages Strain PJM Grid
A rare combination of heat and planned upgrades forced federal intervention to stabilize the regional power supply.
By Arjun Weber ·
The United States Department of Energy declared a power grid emergency for the PJM Interconnection region on Sunday, October 12, 2026. Energy Secretary Chris Wright issued the order to grant PJM temporary emergency authority from October 13 through October 16. The declaration covered thirteen states and the District of Columbia. The primary cause was a collision between unusually warm October weather and the fall maintenance season. Generator and transmission owners took equipment offline for upgrades while demand remained high. This specific combination created a capacity shortfall that required immediate federal attention to keep the regional grid stable.
PJM had previously issued a Capacity Advisory on Friday, October 9, for the following Monday and Tuesday. This marked the first time in history that PJM used this specific procedure. PJM members endorsed this tool in June 2026 for situations where projected conditions indicate an approaching capacity shortfall. The load forecast for Monday, October 12, was approximately 102,000 megawatts of peak demand. The forecast for Tuesday, October 13, was about 104,000 megawatts. These figures were set against previously scheduled generation outages of about 70,000 megawatts plus planned transmission outages. Paul Dajewski, PJM's senior manager for dispatch, noted that this volume of outages is typical for the shoulder season.
On Monday, October 12, PJM issued a Maximum Generation Alert and a Load Management Alert for the next day. The operator also extended the Capacity Advisory through October 14 and issued a Maintenance Outage Recall. These actions followed a forecast of demand reaching approximately 111,500 megawatts or higher. On October 13, PJM extended both alerts through October 14. The operator called on Demand Response programs to cut electricity use. These programs pay customers who sign up in advance to reduce consumption when the grid is stressed. PJM stated that the alerts required no action from customers. Daily electricity use for households stayed normal and no mandatory conservation orders were issued.
The Maximum Generation Alert informed transmission and generation owners that conditions would be tight. This allowed them to defer or cancel equipment maintenance and testing. It also notified neighboring grid operators that exports from PJM might be curtailed. Scheduled transmission line outages further limited how much electricity could move between zones. Generation was bottled in some areas due to these transmission limits. This was particularly true for resources serving congested zones in Washington D.C., Maryland, and Virginia. The affected areas included the BGE, Pepco, and Dominion zones.
The Department of Energy order allowed PJM to call on generators to run in excess of their operating permits. It also authorized PJM to direct data centers and other large electricity users onto their backup generation if necessary. Federal officials explained that PJM wanted to deploy auxiliary, standby, directly connected, or battery storage resources at data centers. This included hyperscaler facilities and other large industrial and commercial customer sites. The goal was to prevent interruptions rather than to announce scheduled blackouts. No blackouts occurred during the emergency period.
This event highlights a new reality for the grid where the shoulder-season reprieve is not what it used to be. Most of the new, rapidly growing demand comes from data centers and other energy-intensive large-load customers. Their consumption does not fall with the weather and operates on a twelve-month, twenty-four hour basis. This expanding demand is outpacing new transmission and electricity supply coming onto the system. Unseasonably hot or cold weather now arrives outside the traditional peak seasons, adding complexity to grid management.
PJM had previously used Department of Energy emergency orders during two unseasonably warm periods in September. The first was from August 31 to September 4 and the second was from September 15 to 18. These orders allowed eligible resources to keep operating beyond normal limits. PJM deployed Demand Response both times. After sunset on those days, PJM had to cover net load as solar output fell faster than electricity use. The October emergency followed a similar pattern of high demand meeting limited supply during the transition to winter.
According to the PJM Winter Outlook released on November 5, 2026, the operator expects sufficient resources to reliably meet demand this winter under expected conditions. PJM expects 182,426 megawatts of operational capacity to serve a forecast winter peak of approximately 147,500 megawatts. This figure includes about 3,200 megawatts of average exports to neighboring systems. That peak would set a new winter record if reached. Michael Bryson, PJM's senior vice president of operations, stated that the goal is to coordinate operations with generation and transmission owners to proactively manage the system when consumers need energy the most.
