PRC-028 & PRC-029 IPs and Data Submittals

PRC-028-1, which went into effect April 1, 2025, governs disturbance monitoring and reporting for inverter-based resources (IBRs) and is meant to ensure that IBRs have sufficient data for evaluating IBR Ride-through performance and for validating models. PRC-029-1 contains the frequency and voltage Ride-through criteria and will go into effect October 1, 2026.

NERC has established phased-in implementation plans (IPs) for both PRC-028-1 and PRC-029-1 to allow additional time for Generator Operators (GOs) to meet the requirements for their IBRs. Bulk Electric System (BES) IBRs and non-BES IBRs, which fall under the newly registered Category 2 GOs, have separate compliance dates under the IPs, and compliance dates also vary by Standard Requirement. When considering your specific compliance deadlines, it is also important to factor in your IBR unit’s commercial operation date (COD) and to have controls in place to ensure you meet the IP deadlines. For example, per the IP for PRC-028-1, BES IBRs operating on or before April 1, 2025, must have 50 percent of their BES IBRs comply with R1-R7 by December 31, 2028, and 100 percent of their BES IBRs comply with R1-R7 by 1January 1, 2030.

The IP for PRC-029-1 is unique because it bifurcates the capability-based (design) elements and the performance-based (operation) elements of R1-R3. With staggered compliance dates for R1-R3 for BES and non-BES IBRs, there is a date by which GOs shall ensure that the design for their IBR units meet the Ride-through criteria and a later date by which GOs shall ensure that the IBR units meet the operations aspect of the requirements. Operations aspects are considered implementation of design settings in the field. Additionally, the IP compliance dates differ for non-BES IBRs to allow existing GOs to prioritize their compliance efforts on the BES IBR assets that pose the highest risk to the BPS. This approach allows for a later compliance date for new registrants that own non-BES IBRs.

These two Standards also introduce new Periodic Data Submittal (PDS) obligations for IBRs. For PRC-028-1 R8, which is currently in effect, an entity shall submit a PDS in Align within 90 calendar days of a failure of recording capability, and upload an accompanying R8 spreadsheet and Corrective Action Plan (CAP) implementation evidence to the Secure Evidence Locker (SEL). The ERO Enterprise is also developing a PDS in Align for requesting an extension of any compliance dates for R1 through R8, provided the entity’s IBRs were COD before the April 1, 2025, effective date of PRC-028-1. Separately, the ERO Enterprise will be creating a PDS in Align for the upcoming PRC-029-1 R4 Requirement, which pertains to hardware limitations that prevent the IBR from meeting Ride-through criteria. The deadline to submit this PDS will be 12 months after the effective date of the Standard (October 1, 2027). It is important to note that the Requirement specifically limits the exception to hardware limitations only, not software.

Proper understanding and implementation of these two protection Standards and related IPs will help ensure that IBRs have appropriate disturbance monitoring capability and Ride-through performance capability during and after voltage or frequency excursions. An effective compliance approach would be for GOs to establish strong internal controls to track and follow through with meeting the phased-in IP deadlines for both these Standards.