NOTICE DATE: June 9, 2026

NOTICE TYPE: M-A060926-01 Reports/Extracts

SHORT DESCRIPTION: GREDP Performance Metrics Posting Issues for Wind/Solar units

INTENDED AUDIENCE: Qualified Scheduling Entities (QSEs)

DAYS AFFECTED: Monthly postings between January 2026 through April, 2026

LONG DESCRIPTION: ERCOT identified an issue affecting Generation Resource Energy Deployment Performance (GREDP) performance metrics resulting from changes implemented under PR447-01, Real-Time Co-Optimization Plus Batteries (RTC+B). As a result, several postings of the Monthly Generation Resource Energy Deployment Performance Report (EMIL ID: NP8-501-ER | Rpt ID: 11022) in the Market Information System (MIS) Certified Area were impacted.

This issue affected Wind and Solar Resources that are not part of an IRR Group and may have impacted reporting periods from December 2025 through April 2026, which were posted on January 4, 2026, February 4, 2026, March 4, 2026 and April 4, 2026 respectively. Specifically, certain intervals in which an IRR did not receive a Base Point Dispatch Instruction that was two MW or more below the IRR's High Sustainable Limit (HSL) used by SCED were erroneously evaluated for GREDP performance reporting.

ERCOT has recalculated all affected GREDP intervals for all 'failed' Wind and/or PVGR Resources. Even though the overall monthly pass/fail metric only changed for a small subset, ERCOT has reposted the monthly reports for all Resources that originally failed.

The following reports have been reposted in the MIS Certified Area:

• December 5-31 2025 (Post-RTC data) Reporting Period:
  • Initially posted: January 4, 2026
  • Repost Date: June 9, 2026
  • Friendlyfile Name: REDP_M_RERUN_Dec2025
•  January 2026 Reporting Period:
  • Initially posted: February 4, 2026
  • Repost Date: June 9, 2026
  • Friendlyfile Name: REDP_M_RERUN_Jan2026
•  February 2026 Reporting Period: 
  • Initially posted: March 4, 2026
  • Repost Date: June 9, 2026
  • Friendlyfile Name: REDP_M_RERUN_Feb2026
• March 2026 Reporting Period:
  • Initially posted: April 4, 2026
  • Repost Date June 9, 2026,
  • Friendlyfile Name: REDP_M_RERUN_Mar2026

Wind and/or PVGR Resources receiving a 'Pass' monthly metric were not recalculated as part of this effort. It is possible that the breakout of the monthly percentages included in the reports may have changed slightly due to the updated calculation, but the overall monthly pass metric remained unaffected.

ACTION REQUIRED: On June 5, 2026, ERCOT removed all impacted monthly products posted between January and April of 2026, from the MIS Certified Area for the QSEs that will have reports rerun and reposted.  Please ensure that the data loaded to your database aligns to the reposted data sets. Any uploaded data from the original files should be replaced.

ADDITIONAL INFORMATION: As part of the resolution, a fix has been implemented and all postings of Monthly Generation Resource Energy Deployment Performance Report as of June 2026 are posting as expected with accurate data. In addition to the aforementioned reruns, ERCOT will post two GREDP files for all QSEs in June 2026. One file for the April 2026 reporting period which was not posted in May due to corrections being assessed and a second file for the expected May 2026 reporting period.

• The April 2026 reporting period will post with friendlyfile name: REDP_M_Apr2026
• The May 2026 reporting period and forward will post as expected with the regular friendlyfile name associated to the monthly posting: REDP_M

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 ClientServices@ercot.com.

If you are receiving email from a public ERCOT distribution list that you no longer wish to receive, please follow this link in order to unsubscribe from this list: http://lists.ercot.com.

dg