NERC Category 2 IBR Registration After May 15, 2026

NERC Category 2 Generator Owner (GO) and Generator Operator (GOP) registrations took effect on May 15, 2026. NERC and the Regional Entities processed registrations in batches from August 2025 through April 2026, and each registered entity received a NERC notification listing it on the Compliance Registry with an effective date of May 15, 2026. Registered Category 2 entities are now subject to the Reliability Standards that apply to them, and the IBR standards bring their own compliance dates over the next several years.

This guide covers who is Category 2, what applies now, and what to do if a facility that meets the criteria was not registered.

Who Is Category 2

Category 2 covers non-BES inverter-based resources that either have or contribute to an aggregate nameplate capacity of 20 MVA or more, connected through a system designed primarily for delivering such capacity to a common point of connection at a voltage of 60 kV or above. BES IBRs were already registered: under inclusion I4 of the BES definition, dispersed power producing resources are BES when they aggregate to more than 75 MVA (gross nameplate) through a system designed primarily for delivering that capacity to a common point of connection at 100 kV or above.

Aggregation is the part most often missed. If several facilities together reach 20 MVA at a common point of connection at 60 kV or above, all of them are Category 2, and each owner and operator registers. For example, two 15 MVA plants sharing a collector system to a common 69 kV point of connection total 30 MVA, so both are Category 2.

Background

NERC disturbance reports, including those on the 2016 Blue Cut Fire and 2017 Canyon 2 Fire events in California and the 2021 and 2022 Odessa events in Texas, found IBRs tripping or reducing output during grid faults. FERC Order No. 901 (October 2023) directed new IBR reliability standards, and in a separate proceeding (Docket No. RR24-2) FERC approved NERC's Rules of Procedure changes to register owners and operators of non-BES IBRs.

What Applies Now

NERC publishes Reliability Standards Compliance Dates for Generator Owners & Generator Operators, updated quarterly, which lists finalized and pending compliance dates for Category 2 GO and GOP registrations. Check it for each facility. The IBR-specific standards and their Category 2 dates:

• PRC-029-2 (ride-through). In effect since October 1, 2026. PRC-029-1 never took effect; PRC-029-2 replaced it on October 1, 2026, and deadlines still count from that date. FERC approved PRC-029-2 on September 30, 2026 (Docket No. RD26-10-000). Design compliance with R1 to R3 for non-BES IBRs starts January 1, 2027, and the operational part of R1 to R3 applies once PRC-028-1 disturbance monitoring is in place for the IBR. R4 applies from October 1, 2026. For an IBR that was in service by October 1, 2026 and whose Generator Owner was responsible for compliance with Reliability Standards for it by that date, hardware-limitation documentation is due no later than 12 months after October 1, 2026, that is October 1, 2027; otherwise it is due by the later of 90 calendar days after the Generator Owner must comply with Reliability Standards for that IBR or October 1, 2026.
• PRC-030-1 (unexpected IBR events). Effective October 1, 2026; non-BES IBRs from January 1, 2027.
• PRC-028-1 (disturbance monitoring). Non-BES IBRs in commercial operation on or before May 15, 2026 need SER, FR and DDR recording by January 1, 2030. Those entering commercial operation later comply by the later of July 1, 2026 or their commercial operation date. R8, restoring failed recording within 90 calendar days or filing a corrective action plan, applies to non-BES IBRs from April 1, 2027.
• MOD-026-2 (model verification). Effective April 1, 2026, and its applicability includes non-BES IBRs. Planning Coordinators and Transmission Planners set their model requirements by April 1, 2027 (R1). Generator Owner submittals, including EMT models where R3 applies, are required from April 1, 2029 (R2 to R6).

Other standards apply to Category 2 GOs and GOPs on the dates in NERC's compliance dates document, and some are still being revised before they apply. Cybersecurity (CIP) standards are written for BES Cyber Systems; check NERC's current list before assuming any CIP obligation for a non-BES plant. Category 2 entities that meet NERC's Generating Availability Data System (GADS) reporting criteria report GADS data from May 15, 2026.

If a Facility Was Not Registered

The registration effective date has passed, but the registration criteria still apply. NERC's FAQ on the Category 2 registration process tells an owner who thinks an asset may meet the criteria, but who was never contacted, to reach out to NERC Registration, which will identify the right Regional Entity. The Regional Entity is set by where the IBR connects to the bulk power system. The Regional Entity collects, through CORES (NERC's Centralized Organization Registration ERO System) or another secure site:

• A completed ERO Enterprise GO/GOP Asset Verification Form
• The interconnection agreement and any amendments
• Operating or third-party agreements
• Operating one-line diagrams from the generation through to the point of interconnection
• Nameplate data for the individual inverters or wind turbines

An owner that concludes on its own that a facility does not meet the criteria still submits these documents; the Regional Entity makes the determination. If the GO has not decided who its GOP will be, the Regional Entity will advise it to register as both GO and GOP until that is settled. A project that meets the Category 2 criteria in its first phase and Category 1 (a BES IBR) once later phases reach commercial operation starts with the Category 2 registration.

Penalties

The maximum civil penalty under section 316A of the Federal Power Act is $1,584,648 per violation per day, the amount FERC set in its January 2025 inflation adjustment. There was no 2026 adjustment: OMB memorandum M-26-11 cancelled the 2026 adjustments because October 2025 CPI data was not available, so agencies continue to use the 2025 amounts.

A Practical Sequence for Registered Owners

1. Confirm the registry entry. Check that each facility, and the GO and GOP for each, matches what the Regional Entity registered.
2. Map standards to facilities. Use NERC's compliance dates document to list what applies to each plant and when.
3. PRC-029-2 design review before January 1, 2027. Compare inverter, plant controller and relay trip settings with the Attachment 1 voltage and Attachment 2 frequency criteria, flag anything that would trip inside the must Ride-through zone, and identify hardware limitations that need R4 documentation.
4. PRC-030-1 process before January 1, 2027. Set up the documented process to identify and analyze qualifying changes in IBR output.
5. PRC-028-1 plan. Schedule SER, FR and DDR installation to the January 1, 2030 date, or the later date for newer plants, and prepare the R8 outage response for April 1, 2027.
6. Models. Confirm with your Transmission Planner what it will require under MOD-026-2 R1, including whether it identifies your plant as a legacy facility that needs an EMT model.

How GridStrong Helps

GridStrong engineers review plant settings against PRC-029-2, build and benchmark positive-sequence and EMT models, and keep PRC-028-1 and PRC-030-1 event evidence in one platform. Talk to an engineer if you are working through any of the steps above.