NOTICE DATE:  November 3, 2014       

NOTICE TYPE:  W-A110314-01 Operations

SHORT DESCRIPTION:  Implementation of shadow price cap for an irresolvable non-competitive constraint in SCED that has exceeded a net margin of $95,000

INTENDED AUDIENCE:  ERCOT Market Participants

DAY AFFECTED:  November 3, 2014

LONG DESCRIPTION: On October 28, 2014, a shadow price cap of $2,000.00 was implemented for the SAPACAD8/HEIGHTTN_HAT1 contingency/constraint pair in accordance with the ERCOT Business Practice, Setting the Shadow Price Caps and Power Balance Penalties in Security Constrained Economic Dispatch. This document requires a new cap to be implemented once the net margin calculation of Section 3.6.3 reaches $95,000. The net margin for this contingency/constraint pair reached $95,000 on Friday, October 31. However, since the prescribed calculation results in the same value as the existing shadow price cap of $2,000, the shadow price cap remains unchanged.

The contingency/constraint pair and shadow price cap are as follows:

Contingency Name	Constraint Name	Description	Maximum Shadow Price
SAPACAD8	HEIGHTTN_HAT1	Loss of the 138 kV line from Caddo Switching Station TNP to Apache TNP overloading the 138/69 kV Heights TNP Autotransformer #1	$2,000.00

ADDITIONAL INFORMATION:  The business practice document, Methodology for Setting Maximum shadow Process for Network and Power Balance constraints, is posted under Key Documents on the Real-Time Market webpage at http://www.ercot.com/mktinfo/rtm/.

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].

If you are receiving email from an ERCOT distribution list that you no longer wish to receive, please follow this link in order to unsubscribe from this list: http://lists.ercot.com.

mm