The ERO Enterprise has moved into Phase 3 (May 2025 to May 2026) of the Category 2 Inverter-Based Resource (IBR) Registration Initiative. Phase 3 consists of completing the registration of Category 2 Generator Owner and Generator Operator (GO/GOP) candidates and conducting specific Category 2 GO/GOP outreach and education. Upcoming outreach and education opportunities include a July 14 NERC webinar providing information on the registration process of Category 2 IBRs, including the new functionality in the Centralized Organization and Registration ERO System (CORES), and an overview of the Electricity Information Sharing Analysis Center (E-ISAC). For webinar registration questions, please contact Tiffany Washington at NERC.

MRO will host a webinar on August 13 highlighting valuable information on the risks associated with the integration of IBRs into the bulk power system. Important registration and compliance considerations for Category 2 IBR Generator Owners and Operators will also be reviewed.

In August, the Regional Entities will begin the registration process for Category 2 GO/GOP candidates that have IBRs meeting the following criteria:

“Category 2” GO/GOP is defined as an entity that owns, maintains, and/or operates non-Bulk Electric System (BES) inverter based generating resources that either have or contribute to an aggregate nameplate capacity of greater than or equal to 20 MVA, connected through a system designed primarily for delivering such capacity to a common point of connection at a voltage greater than or equal to 60 kV.

Note: No new functions have been created; this is a categorization of IBR generation resources owned and/or operated by Category 2 GO/GOPs. Category 1 generating resources include the generator terminals through the high side of the step-up transformer(s) connected to a voltage of 100kV or higher and have an individual nameplate rating of 20MVA or greater, gross plant/facility aggregate nameplate rating greater than 75MVA, and dispersed power producing resources that aggregate to a total capacity greater than 75MVA (gross nameplate rating) that are connected through a system designed primarily for delivering such capacity to a common point of connection at a voltage of 100kV or above.

Phase 3 of the work plan includes finalizing registration assessments of the information provided by Category 2 GO/GOPs. The Regional Entities have been working diligently to validate the responses and may reach out to request more information before finalizing. When the registration assessments have been completed, the regional entities will work with the candidates on completing the CORES registration information for the Category 2 GO/GOP.

On Jan 31, 2025, ERO registration staff posted the ERO Enterprise CMEP Practice Guide: Application of the Registration Criteria for Category 2 Generator Owner and Generator Operator Inverter-Based Resources. This CMEP Practice Guide provides guidance to ERO Enterprise staff to support the consistent application of the revised registration criteria thresholds for Category 2 GO/GOPs. The CMEP Practice Guide includes NERC registry criteria for Category 2 GO/GOPs, Principles of Application (BES definition and Hybrid Resource Guidance), and provides single line diagrams with examples of possible IBR configurations that include both text and diagrams explaining how to apply the registry criteria for non-BES IBRs (Category 2). The examples are not to be considered all-inclusive and are provided for illustrative purposes only.

Reliability Standards Compliance Dates for Generator Owners & Generator Operators have been published to support the continued IBR Registration Initiative. This document provides non-BES IBR owners and operators that meet the registration criteria for Category 2 GO/GOP with final and pending compliance dates for the applicability and enforceability of related Reliability Standards. This document is a great reference for staying up to date on the status of Reliability Standards that apply to Category 2 IBRs.

The Reliability Standards listed below are currently active and enforceable and do not require revisions to apply to Category 2 GO/GOPs.

• BAL-001-TRE
• IRO-010-5
• MOD-032-1
• PRC-012-2
• PRC-017-1
• TOP-003-6.1
• VAR-001-5
• VAR-002-4.1

The compliance date for Category 2 IBR GOs/GOPs is pending FERC approval of the revised GO/GOP definitions.

For questions contact [email protected].

– Pete Pelowski, Senior Reliability Specialist, MRO