NOTICE DATE: September 2, 2025

NOTICE TYPE: W-090225-01 Operations

SHORT DESCRIPTION: Update to the Generic Transmission Limits (GTLs) for the Hill County (SAMSW) Generic Transmission Constraint (GTC).

INTENDED AUDIENCE: ERCOT Market Participants

DAYS AFFECTED: September 17, 2025

LONG DESCRIPTION: A Generic Transmission Constraint (GTC) study has been conducted for Hill County (SAMSW) to reassess the Generic Transmission Limits (GTLs) under planned prior outage conditions.

The purpose of this Notice is to provide timely notification to all ERCOT Market Participants regarding these changes. ERCOT will begin enforcing the updated Generic Transmission Constraint (GTC) for the Hill County area effective September 17, 2025.

Details associated with all GTCs (EMIL ID NP3-770-M , Report ID 11425 ) can be found on the ERCOT Market Information System (MIS) Grid Transmission page under the Generic Transmission Constraints Methodology Secure Area. A Digital Certificate with role ICE_M_VIEW_ECEII is required to access this ECEII data. .

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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