NOTICE DATE: August 19, 2026

NOTICE TYPE: M-A081926-01 Operations

SHORT DESCRIPTION: 2026 Minimum Monthly Ancillary Service Requirements Update

INTENDED AUDIENCE: All Market Participants

DAYS AFFECTED: September 1, 2026

LONG DESCRIPTION: On July 27, 2026, ERCOT issued a Market Notice (M-C072726-01) indicating an issue had been identified in the determination of the minimum quantities of ERCOT Contingency Reserve Service (ECRS) and Non-Spinning Reserve Service (Non-Spin) for 2026. On August 6, 2026, ERCOT filed a request for good cause exception with the Public Utility Commission of Texas (PUCT) in Project No. 55999, seeking approval to continue procuring the posted ECRS and Non-Spin quantities for the remainder of 2026. That filing also described ERCOT's plan to increase Non-Spin in a limited number of hours beginning on September 1, 2026 through year-end 2026 so that the combined minimum MW quantity of ECRS and Non-Spin would equal or exceed the combined minimum MW quantity of Regulation Service Up (Reg-Up) and Responsive Reserve Service (RRS).

To address this, ERCOT has updated the posted minimum Non-Spin Ancillary Service (AS) Requirements in the affected hours - a limited number of month-hour combinations, primarily overnight - so that, for each of those hours, the combined quantity of Non-Spin and ECRS is no less than the combined quantity of RRS and Reg-Up. The updated minimum Non-Spin requirements will be effective beginning September 1, 2026.

ADDITIONAL INFORMATION: The updated minimum monthly Ancillary Services quantities for 2026 have been posted in the Ancillary Service Requirement Methodology report (EMIL ID NP3-783-M, Report ID 13036) on ERCOT's website. The posted quantities reflect minimum requirements only. ERCOT will follow up with a Market Notice if any future upward adjustments to these minimum quantities are made.

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.

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