NOTICE DATE: December 6, 2021

NOTICE TYPE: M-A120621-01 PGRR

SHORT DESCRIPTION: Implementation details of PGRR057, PGRR070, and PGRR072

INTENDED AUDIENCE: All Market Participants

DAYS AFFECTED: December 17, 2021

LONG DESCRIPTION: On December 17, 2021, Planning Guide language associated with Planning Guide Revision Request (PGRR) 057, Responsibilities for Performing Geomagnetic Disturbance (GMD) Vulnerability Assessments; PGRR070, Revised Responsibilities for Performing Geomagnetic Disturbance (GMD) Vulnerability Assessments; and PGRR072, Treatment of Generation Resource Retirement and Mothball in Regional Transmission Plan and Geomagnetic Disturbance Vulnerability Assessment, will be implemented.

These PGRRs modify the ERCOT Planning Guide in order to align with the North American Electric Reliability Corporation (NERC) Reliability Standard TPL-007-4, Transmission System Planned Performance for Geomagnetic Disturbance Events.

ADDITIONAL INFORMATION: Pursuant to Planning Guide Section 1.2.5, Planning Guide Revision Implementation, ERCOT is required to provide notice as soon as practicable, but no later than ten days prior to implementation.

PGRR057, PGRR070, and PGRR072 and associated documents, can be found on the ERCOT website.

Please review the ERCOT website for previous Market Notices related to this subject.

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