1. Lead from the front Texas Nodal http://nodal.ercot.com 1 Registration Market Call June Data Collection Window Aug 14, 2009

2. Lead from the front Texas Nodal http://nodal.ercot.com 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. Lead from the front Texas Nodal http://nodal.ercot.com 3 Agenda Antitrust Admonition Updates and Progress Reminders FAQ / Common Issues Q&A / Open Forum ERCOT asks that you log into the WebEx using your company name then your name. This will allow us to take roll call offline. If you have not logged in with your company name, please use the WebEx chat to tell the host your company is represented

4. Lead from the front Texas Nodal http://nodal.ercot.com 4 Updates and Progress 2009 MAR APR MAY JUN JUL AUG SEP OCT NOV DEC Private Use Network Transmission Data Collection June Window - Non-Wind Transmission / Planning / Protection Data Collection - Iteration 1 - Iteration 2 - Iteration 3 - Iteration 1 - Iteration 2 - Iteration 3 Private Use Network Planning and Protection Data Collection September Window - Wind / All Remaining Sites Transmission / Planning / Protection Data Collection - Iteration 1 - Iteration 2 - Iteration 3 Mapping of Resource Nodes and EPS meters to resource Phase 2 SEM GO-LIVE 8/31 85% Prod Quality 95% Prod Quality 98% Prod Quality 85% Prod Quality 95% Prod Quality 98% Prod Quality 85% Prod Quality 95% Prod Quality 98% Prod Quality Kick Off Market Call

5. Lead from the front Texas Nodal http://nodal.ercot.com 5 Updates and Progress June Window Iteration 2 Status –110 total generation sites Participating in June Window –70 sites have submitted a revision for iteration 2 –67 RARF’s accepted and are complete for Nodal registration –98.55% Production Quality at the end of Iteration 2 –1142 outstanding issues –40 PSSE files have been submitted –Iteration 2 submission window completed on 8/7/09 –June Window Iteration 3 –Starts on 8/14 –Final deadline for June Window submittals is 8/27 –RE’s participating in the June Window that have not submitted corrected RARF’s by 8/27 will be RED on the scorecard when that is released in the coming weeks

6. Lead from the front Texas Nodal Nodal Production – ERCOT Test Certificates ERCOT is requesting volunteers Market Participants to provide test certificates that will enable ERCOT’s ability to: –Support Market Participants during Trials activities by reproducing reported issues –Executing extensive regression testing following each software release to the Nodal Production environment Background: –Previously ERCOT used NODALTEST certificates to access the environment –This was possible as we were not yet integrated with MPIM and ERCOT was acting as each MP’s USA –Going forward with the October Release of the Nodal Production environment, MPIM will be integrated and MP’s USA’s will be the only users permitted to create certificates for that company What ERCOT Needs: –Sept 1, 2009, ERCOT will release all nodal roles to MPIM –ERCOT is asking for volunteer MP’s to generate a certificate for their company containing only these Nodal roles for a user called NODALTEST1 Note that we have placed a 1 on the user to avoid conflicts with the previously used NODALTEST user. –Additionally, please designate this certificate as an API Certificate –Once created, email the NODALTEST1 certificate to smiddleton@ercot.com Note that Scott Middleton will serve as the central point of control for these certificatessmiddleton@ercot.com –Once we have completed the 168 hour test, MP USA’s may revoke this certificate (ERCOT will also destroy it) –ERCOT would like a core set of certificates in place no later than October 1, 2009

7. Lead from the front Texas Nodal FAQ / Common Issues What do I need to show for the normal breaker position for the breaker between the Resource and the Grid? –The breaker normal position for any breaker between the Resource and the connection to the Transmission system needs to be normally closed. Otherwise, the Resource will not be able to be deployed by RUC.

8. Lead from the front Texas Nodal http://nodal.ercot.com 8 Q&A Q&A / Open Forum

9. Lead from the front Texas Nodal http://nodal.ercot.com 9 Appendix

10. Lead from the front Texas Nodal http://nodal.ercot.com 10 June Data Collection Window Schedule Originally presented on 5/22/09

11. Lead from the front Texas Nodal http://nodal.ercot.com 11 Updates and Progress Originally presented on 5/22/09 Receive Audit Report and pre-populated RARF week of 6/8 Conference call with Account Managers starting week of 6/15 Iteration 1 corrections due 7/13/09 (20 business days) Iteration 2 corrections (if needed) due 8/12/09 (15 business days) Iteration 3 corrections (if needed) due 9/1/09 (10 business days)