Mid-Atlantic and portions of the Midwest and South, United States.
Wholesale design: nodal energy and ancillary-services markets with a centralized Reliability Pricing Model capacity construct.
Energy in PJM trades in 2 layers: Day-Ahead Energy Market and Real-Time Energy Market. Participation in Real-Time Energy Market is mandatory. Scheduling and settlement, where the official sources state them, are in the table below.
| Layer | Scheduling | Settlement |
|---|---|---|
| Day-Ahead Energy Market | hourly | day-ahead locational marginal pricing and co-optimized reserve pricing |
| Real-Time Energy Market (mandatory) | five-minute pricing and dispatch | real-time locational marginal pricing and reserve market-clearing prices |
PJM has 6 ancillary-service products, across 5 families — regulation, frequency containment, automatic frequency restoration, reactive power & voltage and black start & restoration: Black Start Service, Non-Synchronized Reserve, Reactive Supply and Voltage Control, Regulation, Secondary Reserve, Synchronized Reserve. Response timing, direction and eligibility for each are in the cards below, as the official sources state them.
Facts below are stated as the official sources state them. A missing line means the source does not state that value — never that the value is zero.
Correct area-control error and help maintain interconnection frequency through automatic control.
Manual 12 effective 2025-10-01 describes the current Phase 1 single-signal implementation.
Provide offline or non-synchronized primary reserve for contingencies.
Provide online primary reserve for contingencies.
Provide additional thirty-minute reserve after or in anticipation of system contingencies.
Supply or absorb reactive power and maintain transmission voltage schedules.
Start without external station power and energize portions of the grid during restoration.
Yes — Reliability Pricing Model is a central capacity market.
Locational capacity auctions procure residual capacity after fixed-resource-requirement and self-supply positions; resources assume Capacity Performance obligations during the delivery year.
Current as of · from the Global Electricity Market Catalogue v1.2.0 (compiled to , CC BY 4.0). Facts belong to the linked official authorities; verify the current rules before design or bidding decisions.
The markets index holds the full set. For what the grid demands of a battery here, see the grid-code ride-through atlas.