PJM Interconnection (PJM) heads into mid-October with federal permission to order backup generators at data centers and other large sites to run. The Department of Energy (DOE) issued the order on October 12 at PJM's request, and it covers October 13 through October 16. Similar orders have followed one another since a January ice storm, through the summer heat and into this fall.
Each rests on section 202(c) of the Federal Power Act and lets PJM, working through its transmission owners and electric distribution companies, direct backup generation to run as a last resort before or during an Energy Emergency Alert level 3 (EEA 3), the stage at which firm load interruption is imminent or already under way. DOE's list of 2026 orders shows PJM holding that authority for September 1 to 8 and September 17 to 18, and Duke Energy Carolinas receiving similar orders twice in September. The October order requires covered backup resources to run when directed, though it excludes generators serving critical needs such as hospitals, 911 centers and water treatment plants. Fuel is the other half of the picture. The U.S. Energy Information Administration (EIA) expects in its October Short-Term Energy Outlook that East Coast distillate inventories, which include diesel, will sit 20% to 30% below their five-year average through the coming winter.
Recurring Orders With Open Questions
Since June 24, PJM has handled backup generation under a written procedure, Attachment O of its emergency operations manual, and its September 1 notice said the order was meant to let utilities prepare in advance to coordinate with large loads. At an October 8 briefing on its broader 202(c) process, PJM asked participating generators to send required information early and report daily run hours during any event, and it pointed backup generator questions to Attachment O. It also said it is assessing how a recent opinion from the federal appeals court in Washington, in Michigan v. DOE, affects certain 202(c) orders. Neither DOE's order pages nor that briefing says whether any data center has actually been directed onto backup power.
A September review by staff of the Federal Energy Regulatory Commission (FERC) and the North American Electric Reliability Corporation (NERC) explains why the paperwork matters. During last winter's cold, PJM, the Electric Reliability Council of Texas (ERCOT) and utilities in the VACAR South area of the Carolinas held the same authority and never used it. ERCOT told reviewers it had no formal channel to reach large-load sites and no information on what their generators could do. PJM lacked certainty about location, size, run duration, switching, telemetry and whether emissions relief extended to customer-owned units. Other operators noted that most data center generators cannot run in parallel with the grid, so their value lies in taking a site's own demand off the system. The only documented use in that review came from Florida utilities, which leaned on municipal and customer-owned units in early February.
A nameplate megawatt figure tells a grid operator very little. What it needs is a plain account of which units work, what load they carry, how they switch over and how long they can run. Technology and operations leaders need that same account to protect their own sites, so building it serves both purposes, and it reflects a broader change in how data centers figure in grid reliability planning.
Every Hour Offered to the Grid Comes Out of the Site's Reserve
When a call comes, the generators carry the site, and every hour they run draws down fuel the facility may need for its own outage a day later. A covered site cannot simply decline, so the planning work comes first. Operators can establish how much runtime the tanks and delivery contract support, how a unit down for maintenance changes that figure and which workloads could pause safely if a directive runs longer than expected. Manufacturers already scheduling production around grid availability offer a template data center teams can borrow.
Diesel Is the Constraint to Plan Around
EIA's outlook explains why fuel deserves attention now. East Coast distillate stocks were 32% below their five-year seasonal average in September. The region burns more distillate than it refines, leaning on Gulf Coast shipments and imports, mostly from Canada, which cover about 15% of regional consumption from December through February. With global stocks also thin, EIA expects importers to have trouble raising volumes enough to close the gap this winter, and it forecasts national retail diesel above $6 per gallon through October before prices ease. Facility fuel costs will depend on delivered bulk prices and contract terms.
A tight regional market is not a shortage at every site. The difference shows up in delivery order during a widespread storm. A fuel review can confirm usable tank volume, which often falls short of nameplate capacity, along with measured burn at the expected load, the supplier's lead time and whether the contract treats delivery as a priority or a best effort. October is a better month to have that conversation than January. Some companies are also investing in other layers of resilience, such as the solar and battery microgrid Siemens commissioned in North Carolina.
Cold Starts Need Their Own Check
Fuel on hand does not guarantee that an engine will start and accept the required load. Application guidance from Cummins identifies coolant heating, starting batteries and, under some conditions, oil and fuel heating as factors in cold-weather readiness. Operators should verify their own equipment's requirements, the delivered fuel's cold-weather properties and the emergency power standards that apply to the installation.
Those details rarely show up in a monthly test run on a mild day. A winter review that ties fuel condition, heaters, starting batteries and transfer procedures to a realistic multi-day scenario gives finance a clear request, whether that turns out to be more fuel, a firmer delivery contract or equipment work.
Backup Power Is Becoming Part of the Grid Plan
A year ago DOE had never issued an order of this kind. PJM has now held the authority repeatedly during 2026, follows a written procedure for it and, along with the Southwest Power Pool, has stakeholder work under way on how large loads take part in emergencies. The orders arrive at short notice and expire within days, so facilities teams are best served entering winter with a verified runtime estimate, a replenishment plan and a clear reading of which emergency instructions apply to their site.
