NOTICE DATE:  February 20, 2014

NOTICE TYPE:  W-A022014-01 Operations

SHORT DESCRIPTION:  Correction to Indicative Operating Reserve Demand Curve (ORDC) postings

INTENDED AUDIENCE:  ERCOT Market Participants

DATES AFFECTED:  January 24, 2014 to February 20, 2014

LONG DESCRIPTION:   As a result of issues identified during analysis of the January 6, 2014 Energy Emergency Alert (EEA) event ERCOT changed the calculation of the Real Time On-Line reserve capacity (RTOLCAP) effective January 24, 2014 with the intention of correcting the error in Load Resource Responsibility Schedules by introducing validation based on the formula Max { min{Telemetered MW, RRS schedule, max[MPC - LPC - (Regulation responsibility +  Non-Spin responsibility  + Down Regulation responsibility), 0]}, 0}. However, ERCOT inadvertently introduced another change which resulted in an incorrect calculation of Real-Time On-Line Reserve Price Adder per interval (RTORPA) and Real-Time Off-Line Reserve Price Adder per interval (RTOFFPA) for the period of January 24, 2014 to February 20, 2014.

When calculating the RTORPA and RTOFFPA, ERCOT only included Resources with Telemetry MW > 0.95*LSL instead of including Resources with Telemetry MW >= 0.95*LSL. This resulted in the exclusion of HSL of Quick Start Generation Resources (QSGR) from the calculation of RTOLCAP when their Telemetry MW was at 0 MW and LSL was 0 MW.

ERCOT has corrected this error and will post the corrected data on February 21, 2014.

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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