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FAC-002-4
Facility Interconnection Studies
FAC-002-4 requires Transmission Planners and Planning Coordinators to study the reliability impact of new interconnections and of existing interconnections seeking to make a qualified change, as each Planning Coordinator defines that term. A Generator Owner interconnecting new generation, or making a qualified change to an existing interconnection, coordinates and cooperates on those studies, including by providing data. A Generator Owner with a fully executed Agreement to conduct a study of a third party Facility interconnecting to its existing Facility has the same duty for those studies.
Who it applies to
- Generator Owners seeking to interconnect new generation Facilities, or with existing interconnections of generation Facilities seeking to make a qualified change as defined by the Planning Coordinator (R2). Category 2 Generator Owners and Generator Operators of non-BES inverter-based resources are not subject to FAC-002-4 unless a later revision of the standard includes them.
- Applicable Generator Owners: a Generator Owner with a fully executed Agreement to conduct a study on the reliability impact of interconnecting a third party Facility to the Generator Owner's existing Facility that is used to interconnect to the Transmission system (R5).
- The standard also applies to Planning Coordinators, Transmission Planners, Transmission Owners and Distribution Providers, which carry the study, data and qualified-change definition obligations in R1, R3, R4 and R6.
Key dates
- January 1, 2024: effective date of FAC-002-4, replacing FAC-002-3.
- January 1, 2025: for a change that is a qualified change under the Planning Coordinator's R6 definition but was not a material modification under FAC-002-3, compliance with R1 to R4 for that change was not required until 12 months after the effective date.
- October 14, 2026: FAC-002-5 passed final ballot under NERC Project 2026-02 as a conforming revision. It leaves R1 to R6 unchanged and adds one exclusion: "end-user Facilities" and "third-party Facilities" exclude Computational Load Sites subject to CLO-001. FAC-002-4 is to be retired immediately before FAC-002-5 takes effect. The NERC Board of Trustees adopted FAC-002-5 with the CLO standards on October 26, 2026, as reported by the American Public Power Association; NERC files them with FERC by December 31, 2026, and FAC-002-5 awaits FERC approval. FAC-002-4 remains in force.
Source
NERC FAC-002-4 (standard text, PDF)October 29, 2026
Requirements
What each requirement asks for, in plain English.
R2 · Coordinate on studies of your new or changed generation
What it means. Each Generator Owner seeking to interconnect new generation Facilities, or whose existing interconnection of generation Facilities is seeking to make a qualified change as defined by the Planning Coordinator under R6, coordinates and cooperates on studies with its Transmission Planner or Planning Coordinator. That includes, but is not limited to, providing data as described in R1 Parts 1.1 to 1.4: the impact on affected systems; adherence to NERC Reliability Standards, regional and Transmission Owner planning criteria and Facility interconnection requirements; steady-state, short-circuit and dynamics studies as necessary; and study assumptions, system performance, alternatives considered and coordinated recommendations.
Evidence an auditor expects. Documents containing the data provided in response to the requests of the Transmission Planner or Planning Coordinator.
R5 · Coordinate on studies of third-party interconnections to your Facility
What it means. Each applicable Generator Owner, meaning one with a fully executed Agreement to study a third party interconnecting to its existing Facility that is used to interconnect to the Transmission system, coordinates and cooperates with its Transmission Planner or Planning Coordinator on studies of requested interconnections to its Facilities, including but not limited to providing data as described in R1 Parts 1.1 to 1.4.
Evidence an auditor expects. Documents containing the data provided in response to the requests of the Transmission Planner or Planning Coordinator.
R6 · Planning Coordinator's definition of qualified change (Planning Coordinator requirement)
What it means. Each Planning Coordinator maintains a publicly available definition of qualified change for the purposes of facility interconnection. This is a Planning Coordinator obligation, but it decides which changes to an existing generation interconnection trigger the Generator Owner's R2 duty.
Evidence an auditor expects. For the Planning Coordinator, evidence that it has maintained a publicly available definition of qualified change. R6 places no evidence obligation on the Generator Owner.
For inverter-based plants
For an existing inverter-based plant, work such as inverter replacement, a capacity change or a control upgrade triggers R2 only if it meets the Planning Coordinator's posted definition of qualified change, so that definition is the first thing to check before the work is scheduled.
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