1. Lead from the front Texas Nodal http://nodal.ercot.com 1 EDS Market Call Weekly Update Jan 30, 2009

2. Lead from the front Texas Nodal http://nodal.ercot.com 2 Agenda Antitrust Admonition Updates / Reminders Focused Input Testing Update Q&A / Open Forum (including API Subgroup) Roll Call

3. Lead from the front Texas Nodal http://nodal.ercot.com 3 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.

4. Lead from the front Texas Nodal http://nodal.ercot.com 4 Updates / Reminders Planned Outages –1/28 (5pm – 9pm) – Storage Maintenance. EDS unavailable during maintenance –2/3 (12pm – 1:00pm) – EDS CA list will be updated to support Go Daddy CA (this has been an ongoing issue which we believe we have resolution to) –2/1 (Sunday 9am – 2pm) – Firewall maintenance on the EDS environment. The EDS environment will be unavailable during this period. Changes to the Friday Call –The EDS 3 Market Call will be expanded in scope. To be included: Relevant program updates Discussions on telemetry issues (FIT and otherwise (e.g. Wind Met data)) Registration updates such as the upcoming RE owned transmission assets Continue to include: API Subgroup, Data and Extracts, Nodal Program Updates Content will be driven by current testing & Nodal Preparation activities All the details are still “under construction” and changes will start with next week’s call

5. Lead from the front Texas Nodal http://nodal.ercot.com 5 Updates / Reminders Changes to the Friday Call (continued….) –Weekly Call Calendar Changes New group under Nodal Groups called “EDS Project” will be added this evening This will consolidate all EDS and API subgroup topics and activities This new group will hold the meeting and related materials going forward Note: the Web Ex Meeting Number and Dial-in information will not be changed The EDS 1,2,3,4 and API Subgroup calendars will remain but will refer users to the EDS Project This will remain in affect until EDS Activities ramp up again –If there are any items you’d like to see added to the weekly call, please send to eds3@ercot.comeds3@ercot.com

6. Lead from the front Texas Nodal http://nodal.ercot.com 6 Updates / Reminders UPDATE: EDS Program Schedule Update –COMPLETE: Preliminary Nodal Integrated Schedule released –COMPLETE: TAC initial review 12/4/08 –COMPLETE: TPTF initial review 12/10/08 3:30-5:30pm (WebEx) Materials: http://www.ercot.com/calendar/2008/12/20081210-TPTFNOD http://www.ercot.com/calendar/2008/12/20081210-TPTFNOD –COMPLETE: TPTF detailed discussion on 12/16 Materials: http://www.ercot.com/calendar/2008/12/20081215-TPTFhttp://www.ercot.com/calendar/2008/12/20081215-TPTF –COMPLETE: TPTF all day workshop on 1/07 Materials: http://www.ercot.com/calendar/2009/01/20090107-TPTFhttp://www.ercot.com/calendar/2009/01/20090107-TPTF –COMPLETE: TPTF session Monday 1/12 in the afternoon continuing Tuesday 1/13 all day Materials: http://www.ercot.com/calendar/2009/01/20090112-TPTFhttp://www.ercot.com/calendar/2009/01/20090112-TPTF –COMPLETE : TPTF session 1/26 – continued discussions on the Nodal Integrated schedule Materials: http://www.ercot.com/calendar/2009/01/20090126-TPTFhttp://www.ercot.com/calendar/2009/01/20090126-TPTF –TAC Presentation on 2/5 – TPTF has voted the new Nodal Schedule through to TAC –Board Presentation 2/17 – Pending TAC approval, the Board presentation will be the final approval prior to the PUCT

7. Lead from the front Texas Nodal http://nodal.ercot.com 7 Focused Input Testing Update Note that the testing scheduled for 2/10 – 2/12 has been canceled Next testing will take place 2/24 – 2/26 FIT II Assessment reports will be posted at: http://nodal.ercot.com/readiness/eds3/documents/index.html http://nodal.ercot.com/readiness/eds3/documents/index.html Reminder: remaining FIT windows will only review telemetry and state estimator convergence. SCED inputs will be removed from FIT until further notice. ALL TIMES ARE CENTRAL DurationStart date and timeEnd date and time 27 hrs (3x9) February 24 - 8:00 amFebruary 26 - 5:00 pm 27 hrs (3x9) March 10 - 8:00 amMarch 12 - 5:00 pm 27 hrs (3x9) March 24 - 8:00 amMarch 26 - 5:00 pm

8. Lead from the front Texas Nodal http://nodal.ercot.com 8 Focused SE & Security Constrained Economic Dispatch Testing (SCED) FIT II Assessment reports will be posted at: http://nodal.ercot.com/readiness/eds3/documents/index.htmlhttp://nodal.ercot.com/readiness/eds3/documents/index.html Key Numbers –92.49% Test Average Convergence –14 of the 27 Test Hours had 100% Convergence

9. Lead from the front Texas Nodal http://nodal.ercot.com 9 Q&A Q&A / Open Forum