NOTICE DATE: December 5, 2011

NOTICE TYPE: M-A120511-01 SCR

SHORT DESCRIPTION: Implementation details of SCR763

INTENDED AUDIENCE: ERCOT Market Participants

DAY AFFECTED: December 9, 2011

LONG DESCRIPTION: On December 9, 2011, ERCOT will implement System Change Request (SCR) 763, Modify COP Validation Rule for RRS, which was approved by the ERCOT Board on July 19, 2011.

The Emergency Ramp Rate that is currently used in the Current Operating Plan (COP) validation check of Responsive Reserve (RRS) responsibility is limited by the COP High Sustained Limit (HSL) for the same hour, which can cause some COP submissions to be rejected even when the RRS responsibility is valid.

SCR763 modifies the existing COP validation to use the highest Emergency Ramp Rate value from the registered Emergency Ramp Rate curve as an input to the COP validation check of RRS responsibility; thus, reducing the potential for COP rejections.

ADDITIONAL INFORMATION: SCR763 and associated documents can be found on the ERCOT website, under Market Rules, at http://www.ercot.com/mktrules/issues/scr/750-774/763/index.

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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