NOTICE DATE: March 21, 2013

NOTICE TYPE: M-A032113-01 NPRR

SHORT DESCRIPTION: Implementation detail for NPRR456

INTENDED AUDIENCE: ERCOT Market Participants

DAY AFFECTED: April 25, 2013

LONG DESCRIPTION: On April 25, 2013, ERCOT will implement Nodal Protocol Revision Request (NPRR) 456, Clarification of Definition of Electrically Similar Settlement Points and Heuristic Pricing Posting, which was approved by the ERCOT Board on July 17, 2012. This Nodal Protocol Revision Request (NPRR) removes the rating requirement in the current definition for Electrically Similar Settlement Points and introduces a daily public report to post the heuristic pricing associations for Day-Ahead Market (DAM) and Real-Time Market (RTM) price calculations.

Details for the new daily public report containing a mapping of any Electrical Bus to another Electrical Bus for purposes of heuristic pricing as described in Section 4.5.1(8), DAM Clearing Process, and Section 6.6.1, Real-Time Settlement Point Prices of the ERCOT Nodal Protocols can be found in the following report.

Report Name	EMIL ID	Report Type ID	Frequency
Electrical Bus Mapping for Heuristic Pricing	NP4-231-CD	13098	Daily

The new report will be posted on MIS and on ERCOT.com.

On ERCOT.com, the file will display on two pages:

· http://www.ercot.com/mktinfo/dam/ under Day-Ahead Supporting Information

· http://www.ercot.com/mktinfo/rtm/ under Real-Time Supporting Information

On MIS, the file will display on two pages:

· Markets Day-Ahead Market Landing page, Day-Ahead Public Information portlet.

· Markets Real-Time Market Landing page, Significant System Conditions portlet

The file naming conventions for the new report:

cdr.00013098.0000000000000000.YYYYMMDD.HHMMSS.DAMSCEDEBUSMAPPINGNP4231_xml.zip

cdr.00013098.0000000000000000.YYYYMMDD.HHMMSS.DAMSCEDEBUSMAPPINGNP4231_csv.zip

Refer to the Current Day Reports XSD V6.6 posted on ERCOT.com at http://www.ercot.com/services/mdt/xsds/ for further report information.

ADDITIONAL INFORMATION: Pursuant to Protocol Section 21.6, Nodal Protocol Revision Implementation, ERCOT is required to provide notice as soon as practicable, but no later than ten days prior to implementation.

NPRR456 and associated documents can be found on the ERCOT website, under Market Rules, at

http://www.ercot.com/mktrules/issues/nprr/451-475/456/index.

Information on upcoming releases can be found on the ERCOT Multi Year Project Priority List (PPL) at

http://www.ercot.com/services/projects/.

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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