NOTICE DATE: April 28, 2025

NOTICE TYPE: M-A042825-01 Operations

SHORT DESCRIPTION: Non-Spin Ancillary Service Plan April-to-May Transition

INTENDED AUDIENCE: All Market Participants

DAYS AFFECTED: April 30, 2025

LONG DESCRIPTION: ERCOT is providing notice of the seasonal increase of Non-Spinning Reserve Service (Non-Spin) quantities in alignment with the posted 2025 annual Ancillary Service (AS) requirements.  Although the planned monthly values have not changed, the seasonal increase from April to May is significant.  When a similar increase occurred in May 2024, ERCOT experienced Day Ahead Market (DAM) AS Insufficiency.  This notice is to provide awareness of the increase and avoid a similar outcome.

The minimum monthly Ancillary Services quantities have been posted to the ERCOT Website in the reports titled Projected Ancillary Service Requirements (EMIL ID: NP3-782-EX | Report Type ID: 13020 | link) or Ancillary Service Requirement Methodology (EMIL ID: NP3-783-M | Report Type ID: 13036 | link). The hourly requirements for Non-Spin in May 2025 increased between 732 MW and 1,775 MW in comparison to same hour's requirement in April 2025 due to increased net load forecast uncertainty historically experienced in May.

ACTION REQUIRED: ERCOT requests all Market Participants to take note of the posted AS requirements for May 2025 when submitting AS offers in the DAM starting on April 30, 2025.

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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