NOTICE DATE: May 25, 2022

NOTICE TYPE: M-A052522-01 Settlements

SHORT DESCRIPTION: Error Identified in Calculation of Net Power Consumption Values Used in Ancillary Service Imbalance Payments and Charges

INTENDED AUDIENCE: All Market Participants

DAYS AFFECTED: June 1, 2014 to Present

LONG DESCRIPTION: ERCOT has identified an error in the calculation of Real-Time Controllable Load Resource (CLR) net power consumption (RTCLRNPC) and Real-Time non-Controllable Load Resource (NCLR) net power consumption (RTNCLRNPC) impacting Real-Time Ancillary Service Imbalance Payments and Charges.  Instead of using the average of the four-second telemetered net power consumption values over each 15-minute interval, as required by the definitions of RTCLRNPC and  RTNCLRNPC in paragraph (7) of Section 6.7.5, Real-Time Ancillary Service Imbalance Payment or Charge, ERCOT’s systems have been using the last telemetered net power consumption value in each 15-minute interval.  This error is limited to CLR and NCLR net power consumption values and does not impact other billing determinants used in the calculation of Real-Time Ancillary Service Imbalance Payments and Charges.  ERCOT has determined that the error dates back to the implementation of NPRR568, Real-Time Reserve Price Adder Based on Operating Reserve Demand Curve, on June 1, 2014.  ERCOT has developed a solution to this error and will implement the solution as part of the 2022-R3 release on May 26, 2022. 

Given limitations in the availability of data for much of the affected period, ERCOT has determined that it is not possible to precisely determine the impact of the error on Market Participants.  ERCOT’s expectation is that the error would have positively impacted QSEs receiving payments in some intervals and negatively impacted them in other intervals, and that the net impact on each QSE could be positive or negative. ERCOT similarly expects that the net impact on each QSE representing Load Serving Entities (LSEs) could be positive or negative.  ERCOT is undertaking an analysis to identify impacts during several sampled periods affected by price adders to develop a better understanding of the potential scale of impacts.  ERCOT will share this analysis with stakeholders as soon as it is available.

CONTACT: If you have any questions, please contact your ERCOT Account Manager. You may also call the general ERCOT Client Services phone number at (512) 248-3900 or contact ERCOT Client Services via email at [log in to unmask].

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