1 Cutover Market Call November 28, 2010

2 Antitrust Admonition ANTITRUST ADMONITION ERCOT strictly prohibits Market Participants and their employees who are participating in ERCOT activities from using their participation in ERCOT activities as a forum for engaging in practices or communications that violate the antitrust laws. The ERCOT Board has approved guidelines for members of ERCOT Committees, Subcommittees and Working Groups to be reviewed and followed by each Market Participant attending ERCOT meetings. If you have not received a copy of these Guidelines, copies are available at the Client Relations desk. Please remember your ongoing obligation to comply with all applicable laws, including the antitrust laws. DISCLAIMER All presentations and materials submitted by Market Participants or any other Entity to ERCOT staff for this meeting are received and posted with the acknowledgement that the information will be considered public in accordance with the ERCOT Websites Content Management Operating Procedure.

3 General Updates / Reminders

4 Full-System Test / Nodal Cutover: Communication Items A hotline call will be made on the day of the test to communicate the start time of the test (approximately 2-3 hours prior to start) An All-QSE VDI will be issued immediately prior to the start of the test –The VDI will be define the “test period” to begin when the first QSE is brought under Nodal control and to end at 23:59:59 CST on Nov 30 Market WebEx: –A Market-facing WebEx will be provided during the following times: Nov 28 – 11:00 to 17:00 (six hours) Nov 29 – 06:00 to 23:59 (all day) Nov 30 – 00:00 to 23:59 (all day) Dec 01 – 00:00 to 23:59 (all day)

5 Full-System Test / Nodal Cutover: Timeline DateTimeEvent 11/2811:00Open Market WebEx 11:30Pre-test meeting for Nodal Support Staff 12:00Hotline call by ERCOT Operators to announce the start time Market Notice to be sent out with the cut-over start time Operators to start using OC3s to manage congestion 14:00Hotline call to QSEs/TOs to announce the start of cut-over ERCOT Operators begin switching QSEs to Nodal control 14:45All QSEs switched to Nodal control Hotline call to announce that all QSEs are on Nodal control 17:00Recess Market WebEx 18:00-18:30ERCOT staff transitions from day-side to night-side support 11/2906:00Resume Market WebEx 06:00-06:30ERCOT staff transitions from night-side to day-side support 18:00-18:30ERCOT staff transitions from day-side to night-side support 11/3006:00-06:30ERCOT staff transitions from night-side to day-side support 18:00-18:30ERCOT staff transitions from day-side to night-side support 12/100:00Nodal Market Go-Live/VDI for QSEs to end 06:00-06:30ERCOT staff transitions from night-side to day-side support 18:00-18:30ERCOT staff transitions from day-side to night-side support 23:59End Market WebEx

6 Questions