The dates that matter to inverter-based resource owners.

Generator Owners of applicable non-BES inverter-based resources comply with the design portion of R1 to R3 by the later of this date or the PRC-029-1 effective date (October 1, 2026), so this date governs.

Non-BES inverter-based resources: within 90 calendar days of discovering a recording failure, restore it or submit a Corrective Action Plan to the Regional Entity.

Inverter-based resources, BES and non-BES, in service by October 1, 2026 whose Generator Owner was already responsible for compliance: supporting documentation for any applicable hardware limitation is due 12 months after the PRC-029-1 effective date of October 1, 2026, which is this date. Owners not yet responsible for compliance on October 1, 2026, and qualifying long-lead projects that enter service later, submit by the later of 90 calendar days after they must comply or the PRC-029-2 effective date (October 1, 2026).

R1 to R7 at 50 percent of an entity's BES inverter-based resources in commercial operation by April 1, 2025 (all of them if it monitors only one). No 2028 step for non-BES resources.

ERCOT: monitoring equipment installed and configured at inverter-based resources commissioned before July 25, 2024. Newer resources follow commissioning-based dates.

Compliance begins for R2 to R6, including the EMT model requirements, 36 months after the April 1, 2026 effective date. First periodic submittals follow the implementation plan's initial performance dates.

R1 to R7 at all BES inverter-based resources in commercial operation by April 1, 2025 and all non-BES inverter-based resources in commercial operation by May 15, 2026. Newer resources comply within 15 months of the effective date or at commercial operation, whichever is later.

PRC-029-2 takes effect, replacing PRC-029-1, which never took effect. The implementation plan still counts its deadlines from the PRC-029-1 effective date, which is this same date, October 1, 2026. Generator Owners of BES resources comply with the design portion of R1 to R3, and with R4, from this date; the operation portion follows PRC-028-1 monitoring.

Takes effect. Requires a documented process to identify a complete loss of plant output, or a real power change of at least 20 MW and at least 10 percent of gross nameplate within 4 seconds (excluding listed causes such as resource variability and dispatch), and to analyze each such event within 90 days.

Takes effect for synchronous generators, Type 1 and Type 2 wind and synchronous condensers. Ride-through for inverter-based resources is covered by PRC-029-2.

Adopted by the NERC Board of Trustees to replace PRC-029-1, which never took effect. FERC approved it on September 30, 2026, and it took effect October 1, 2026.

NERC registration deadline for Category 2 Generator Owners and Operators of non-BES inverter-based resources that have or contribute to 20 MVA or more aggregate, delivered to a common point at 60 kV or above.

Takes effect, replacing MOD-026-1 and retiring MOD-027-1. Extends model verification for inverter-based resources to full plant models, including EMT models. Compliance with R2 to R6 begins April 1, 2029.

ERCOT: removes the NOGRR 255 interim milestone of 50 percent by August 1, 2026, leaving August 1, 2028 for resources commissioned before July 25, 2024.

BES inverter-based resources: within 90 calendar days of discovering a recording failure, restore it or submit a Corrective Action Plan to the Regional Entity.

Disturbance monitoring for inverter-based resources takes effect, with phased compliance dates.