NOTICE DATE: December 9, 2024

NOTICE TYPE: M-A120924-01 Operations

SHORT DESCRIPTION: Incorrect Resource High Sustained Limit (HSL) Telemetry and Failure to Follow Dispatch Instructions Adversely Impacting ERCOT Operations

INTENDED AUDIENCE: All Market Participants

DAYS AFFECTED: Effective Immediately

LONG DESCRIPTION: ERCOT's Security Constrained Economic Dispatch (SCED) system relies on accurate HSLs to dispatch Resources to control system balance. If the QSE-provided HSL indicates a Resource can provide up to a certain number of MWs (the HSL), SCED takes that data into account when determining Base Points (i.e., Dispatch Instructions). Resources not following a Dispatch Instruction may cause imbalances on the ERCOT System that require ERCOT operators to take additional, manual actions to maintain frequency control.

ERCOT recently began experiencing sustained frequency control concerns resulting from QSEs telemetering incorrect HSLs for numerous Intermittent Renewable Resources (IRRs) and the IRRs not following Dispatch Instructions. ERCOT Protocols § 6.4.6(1) requires QSEs to provide ERCOT "accurate telemetry of the current capability of each Resource" including the HSL. Protocols § 6.5.5.2(3) requires QSEs for IRRs to, "set the HSL equal to the current net output capability of the facility." Additionally, Protocols 6.5.7.9(1) requires a QSE to, "comply fully and promptly with a Dispatch Instruction issued to it." Thus, QSEs telemetering incorrect HSLs for IRRs violate Protocols §§ 6.4.6(1) and 6.5.5.2 (3) and QSEs not following Dispatch Instructions violate Protocols § 6.5.7.9(1).

ERCOT sent numerous Requests for Information (RFIs) regarding the issues and potential corrective actions implemented and discussed the issues at the Reliability Operations Subcommittee (ROS) November 7, 2024 meeting and Congestion Management Working Group (CMWG) December 6, 2024 meeting. While ERCOT has maintained reliability and operated the ERCOT System within NERC-prescribed limits, ERCOT has not seen sufficient corrective actions and continues to see adverse impacts from IRRs telemetering incorrect HSLs and/or not following Dispatch Instructions. ERCOT control room personnel will take all necessary and prudent actions, including instructing breaker operations, to address reliability concerns.

Furthermore, Market Participants who received RFIs but not yet responded should review the RFIs, implement corrective actions as soon as possible, and timely respond to the RFIs. Failure to timely respond to ERCOT RFIs violates Public Utility Commission of Texas Rule § 25.503(f)(10). ERCOT will send the data regarding Market Participants failing to follow the Protocols or Commission Rules to the ERCOT Reliability Monitor.

ACTION REQUIRED:  QSEs representing IRRs must set IRRs' HSL equal to the current net output capability of the facility and comply fully and promptly with Dispatch Instructions.

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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