NOTICE DATE: September 14, 2026

NOTICE TYPE: W-A091426-01 Operations

SHORT DESCRIPTION: Revision of the Interface and Generic Transmission Limits (GTLs) Associated with Greater Valley Area (VALEXP, VALIMP, NelsonSharpe_RioHondo & NorthEd_lobo) Generic Transmission Constraints (GTCs)

INTENDED AUDIENCE: ERCOT Market Participants

DAYS AFFECTED: September 16, 2026

LONG DESCRIPTION: ERCOT has identified revised Interface and Generic Transmission Limits (GTLs) for the Greater Valley area Generic Transmission Constraints (GTC) based on recent stability assessments performed in accordance with Section 5.3.5 of the ERCOT Planning Guide. The revised limits reflect recently completed transmission projects in the area.

The purpose of this Notice is to provide contemporaneous notification to all ERCOT Market Participants of these updates. ERCOT will begin enforcing the updated Greater Valley Area (Valley Export, Valley Import, NelsonSharpe_RioHondo & NorthEd_lobo) GTC Generic Limits on September 16, 2026.

Details associated with all GTCs (EMIL ID NP3-770-M , Report ID 11425 ) can be found on the Grid Transmission page on ERCOT Market Information System (MIS) Secure Area under the Generic Transmission Constraints Methodology section. 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 [email protected].

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