NOTICE DATE: December 19, 2017

NOTICE TYPE: W-A121917-01 Operations

SHORT DESCRIPTION: 2018 Minimum Monthly Ancillary Service Requirements

INTENDED AUDIENCE: ERCOT Market Participants

DAY AFFECTED: January 1, 2018

LONG DESCRIPTION: On December 12, 2017, the ERCOT Board of Directors approved the 2018 ERCOT Methodologies for Determining Ancillary Service Requirements (“AS Methodology”). The approved changes affect the methodology for determining Non-Spinning Reserves to be procured. The new requirements will be effective beginning January 1, 2018. ERCOT’s December 12, 2017 presentation to the ERCOT Board of Directors provides additional details about these changes.

Per the 2018 AS Methodology, the minimum monthly Ancillary Services quantities for 2018 have been posted on ERCOT’s Market Information System (MIS). An ERCOT Digital Certificate is required to access the MIS. The posted quantities reflect minimum requirements only. ERCOT will follow-up with a Notification if any upward adjustments to these minimum quantities are made.

On December 12, 2017, the ERCOT Board of Directors also approved Nodal Protocol Revision Request (NPRR) 815, Revise the Limitation of Load Resources Providing Responsive Reserve (RRS) Service. The minimum monthly Ancillary Service quantities described above do not include the impacts of NPRR815. Once the ERCOT system changes to implement NPRR815 are completed, ERCOT will post revised minimum Ancillary Service quantities and issue a follow-up Market Notice. ERCOT will also notify market participants 30 days before the NPRR815 language is effective.

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 [log in to unmask].

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