PJM's new large-load registry will ask about your backup generators, fuel, and permit limits.

For most large buildings, the backup generator has been a private matter between the owner, the air permit, and the maintenance contractor. On PJM Interconnection's grid, it is about to become planning data.

Confirmed facts: On October 9, 2026, the Federal Energy Regulatory Commission issued an order in Docket No. ER26-3515-000 (197 FERC ¶ 61,019) on a package PJM filed on August 13. FERC accepted two pieces, effective October 12, 2026: a definition of "Large Load" and a Large Load Registry. It rejected the rest, and directed PJM to submit a compliance filing within 30 days of the order.

Under the accepted definition, a Large Load is end-use customer load with a cumulative peak of 50 MW or more at a single electrical site behind one or more points of interconnection. Affiliated load facilities within a one-mile radius count as a single site, so an owner's smaller affiliated facilities placed close together can add up to one Large Load. FERC noted the definition covers Large Loads regardless of when they went into service, not only new ones.

According to the order, PJM described the registry as including the customer and a description of the load, its location, in-service dates for each increment of load, the point of interconnection, peak load and ramp schedule, telemetry specifications, "backup generation including fuel type and permitting limitations," service agreements with the load-serving entity, and utility points of contact. The load-serving entity is obligated to provide the information, and the local electric distributor may fill gaps. Registry data will be available to state utility commissions, transmission owners, distributors, load-serving entities, PJM's market monitor, and FERC under existing confidentiality rules; PJM will post only aggregated data publicly. FERC also said it expects PJM to trim the list of required items to remove those tied to the rejected parts of the proposal. The final field list will come through the compliance filing and PJM's manuals.

What FERC rejected was the core of PJM's plan, the Interim Resource Adequacy Service. PJM had described it as letting large loads connect without bringing new capacity, on the condition that they reduce load or switch to on-site backup resources under specific emergency conditions. FERC found that the proposal appeared to place obligations directly on retail customers and to dictate which retail customers would be curtailed, matters it said belong to the states, and it strongly encouraged states to keep working on curtailment rules. Utility Dive reported that a PJM spokesperson said the operator is reviewing the order, and that Commissioner David Rosner, in a concurring statement, called on state regulators to set clear rules for which customers are curtailed first.

Backup generators have already been pulled into grid operations this year. The U.S. Environmental Protection Agency says that in spring and summer 2026, Department of Energy emergency orders under Federal Power Act section 202(c) directed some entities to require data centers and other large load customers to run back-up generation as a last resort before declaring an Energy Emergency Alert Level 3. EPA states that it treats operation under those orders as emergency operation, so those hours do not count toward the 50 non-emergency hours certain emergency engines are allowed under the federal stationary-engine rules.

FRG operational interpretation (not a legal or compliance finding): The direction is clear even though the details are not final. Grid planners want to know what a large site can do on its own power, and the questions they ask line up with paperwork many facilities keep in pieces: how much generation is on site, what it burns, and what its permit allows.

A site at or near 50 MW in PJM territory can get ahead of the request without waiting for the manuals. Keep one current record per site with generator count and rating, fuel type and on-site storage, air permit conditions and operating-hour limits, and engine classification. Keep hour-meter logs that separate testing, maintenance, emergency operation, and any operation under a declared emergency order, since those categories are treated differently. Know who your load-serving entity contact is, because that is who will be asked.

The same record matters at the other end of a site's life. When generation is consolidated, replaced, or removed during a decommissioning, the generator inventory, permit status, and utility contacts should be part of the exit file rather than something reconstructed afterward. Confirm what any specific site must report with the serving utility and the air permitting authority; this summary does not establish any site's obligations.

If you are taking inventory of on-site generation, refreshing critical power, or planning a site exit, Facility Recovery Group can help document what is installed and scope the removal or recovery of equipment you no longer need. Bring your generator list and permit conditions to the first conversation.