NOTICE DATE: September 14, 2026

NOTICE TYPE: M-C072726-02 Legal

SHORT DESCRIPTION: PUCT Approval of Good Cause Exception to 2026 Ancillary Services Methodology

INTENDED AUDIENCE: All Market Participants

DAYS AFFECTED: September 11, 2026

LONG DESCRIPTION: On August 6, 2026, ERCOT filed with the Public Utility Commission of Texas (PUCT) in Project No. 55999 a request for a good cause exception to allow it to continue using a lower minimum megawatt (MW) quantity for ERCOT Contingency Reserve Service (ECRS) and Non-Spinning Reserve Service (Non-Spin) than the 2026 Ancillary Services Methodology would otherwise have required for the remainder of 2026.  As described in Market Notice No. M-C072726-01 and ERCOT's subsequent filing to the PUCT, the discrepancy in the minimum MW quantities for these two Ancillary Services was due to issues with the probabilistic model used to determine the minimum MW quantities.

On September 11, 2026, the PUCT issued its Order Granting Good Cause Exception granting ERCOT's request.  Accordingly, ERCOT will continue to use the currently posted minimum MW quantities for all Ancillary Services, including ECRS and Non-Spin, until the 2027 Ancillary Services Methodology is approved and implemented.

ADDITIONAL INFORMATION: The hourly quantities of all Ancillary Services for 2026, including ECRS and Non-Spin, are posted to the Ancillary Service Requirement Methodology page of the ERCOT website.  Note that, as of September 1, 2026, these minimum MW quantities reflect the increase to Non-Spin explained on page 7 of ERCOT's filing to the PUCT and in Market Notice No. M-A081926-01.

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 [email protected].

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