Revisit RTM True-Up Schedule and Invoicing ERCOT Settlements SEWG 08/18/2011

Protocols – Zonal vs Nodal 9.2.3 Initial Statements ERCOT will issue Initial Statements by the end of the tenth (10th) day following the Operating Day. If the tenth (10th) day is not a Business Day, ERCOT will issue the Initial Statement on the next Business Day thereafter. Nodal 9.5.4 RTM Initial Statement If the tenth day is not a Business Day, then ERCOT shall issue the RTM Initial Statement on the next Business Day after the tenth day. February 10, 2009

RTM Initial Schedule = 7 Op Days / Invoice Date RTM Initial Operating Day Post Date # of days Day of Posting Invoice Date 11/19/2010 11/29/2010 10 Mon 12/9/2010 11/20/2010 11/30/2010 Tue 11/21/2010 12/1/2010 Wed 11/22/2010 12/2/2010 Thu 11/23/2010 12/3/2010 Fri 11/24/2010 12/6/2010 12 11/25/2010 11 11/26/2010 12/16/2010 11/27/2010 12/7/2010 11/28/2010 12/8/2010 12/10/2010 12/13/2010 12/27/2010 12/4/2010 12/14/2010 12/5/2010 12/15/2010 12/17/2010 12/20/2010 12/30/2010 = 7 Op Days / Invoice Date February 10, 2009

Protocols – Zonal vs Nodal 9.2.4 Final Statements Final Statements will be issued at the end of the fifty-ninth (59th) calendar day following the Operating Day. In the event that the fifty-ninth calendar day falls on a weekend or holiday, then the Final Settlement Statement will be issued on the following Business Day. Nodal 9.5.5 RTM Final Statement ERCOT shall issue an RTM Final Statement for each Statement Recipient for a given Operating Day on the 59th day after the Operating Day, unless that 59th day is not a Business Day. February 10, 2009

RTM Final Schedule = 7 Op Days / Invoice Date RTM Final Operating Day Post Date # of days Day of Posting Invoice Date 11/19/2010 1/17/2011 59 Mon 1/27/2011 11/20/2010 1/18/2011 Tue 11/21/2010 1/19/2011 Wed 11/22/2010 1/20/2011 Thu 11/23/2010 1/21/2011 Fri 11/24/2010 1/24/2011 61 11/25/2010 60 11/26/2010 2/3/2011 11/27/2010 1/25/2011 11/28/2010 1/26/2011 11/29/2010 11/30/2010 1/28/2011 12/1/2010 1/31/2011 12/2/2010 12/3/2010 2/10/2011 12/4/2010 2/1/2011 12/5/2010 2/2/2011 12/6/2010 12/7/2010 2/4/2011 12/8/2010 2/7/2011 12/9/2010 12/10/2010 2/17/2011 = 7 Op Days / Invoice Date February 10, 2009

Protocols – Zonal vs Nodal 9.2.6 True-Up Statement True-Up Statements will be issued six (6) months following the Operating Day provided that ERCOT has received and validated usage data from at least ninety-nine percent (99%) of the total number of Electric Service Identifiers (ESI IDs).... Methodology: 365 days / 2 = 182 days Nodal 9.5.8 RTM True-Up Statement ERCOT shall issue RTM True-Up Statements 180 days following the Operating Day, if ERCOT has received and validated usage data from at least 99% of the total number of Electric Service Identifiers (ESI IDs)…. February 10, 2009

RTM True-Up Schedule = 7 Op Days / Invoice = 9 Op Days / Invoice Date Operating Day Post Date # of days Day of Posting Invoice Date 11/19/2010 5/20/2011 182 Fri 5/26/2011 11/20/2010 5/23/2011 184 Mon 11/21/2010 183 11/22/2010 6/2/2011 11/23/2010 5/24/2011 Tue 11/24/2010 5/25/2011 Wed 11/25/2010 Thu 11/26/2010 5/27/2011 11/27/2010 5/31/2011 185 11/28/2010 11/29/2010 6/9/2011 11/30/2010 12/1/2010 181 12/2/2010 180 12/3/2010 6/1/2011 12/4/2010 12/5/2010 6/3/2011 12/6/2010 6/6/2011 12/7/2010 12/8/2010 6/16/2011 12/9/2010 6/7/2011 12/10/2010 6/8/2011 = 7 Op Days / Invoice = 9 Op Days / Invoice Date February 10, 2009

6/29 has 9 RTM True-Ups in total (from zonal and nodal) RTM True Up Schedule 6/29 has 9 RTM True-Ups in total (from zonal and nodal) If Zonal and Nodal had same posting timeline, 7 True-Ups would have been invoiced for this week Due to 2 day overlap, additional 2 invoices in same week zonal posted on OD+182 Nodal posts on OD+180 The settlement schedule is defined and available in the Settlement Calendar February 10, 2009