1. http://nodal.ercot.com 1 Market Trials Outage Scheduling Qualifications Weekly Update March 4, 2010

2. 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. http://nodal.ercot.com 3 Agenda Anti-trust Admonition Environment Report –Planned / unplanned outages –Known Issues –CIM Load Standing Reports and Updates –General reminders / updates Qualification Update Question and Answers / General Discussion ERCOT asks that Market Participants log into the WebEx session using their company name and then their name. This will allow ERCOT to take roll-call offline

4. Market Trials 2010 Roadmap http://nodal.ercot.com 4

5. http://nodal.ercot.com 5 Environment Report: Planned / Unplanned Outages Planned Outages –03/05/10 – 03/07/10 Maintenance activities are planned during this period in preparation for Market Trials Phase 4. Outage Scheduler (OS) and OS UI will be unavailable during this period. (note that 3/5 is typically a supported day; due to the size and scope of the release, it will necessary to bring the environment down during this period as well) Unplanned Outages –N/A

6. http://nodal.ercot.com 6 Environment Report: Known Issues Reminder: ERCOT will post known issues every Friday to the readiness center at: http://nodal.ercot.com/readiness/markettrials/os/index.html http://nodal.ercot.com/readiness/markettrials/os/index.html No new known issues this week

7. http://nodal.ercot.com 7 Standing Reports and Updates: General reminders / updates QSE Telemetry 1 point required for State Estimator still missing (~99% complete for nodal telemetry) 8 points required for SCED execution still missing (~99% complete for nodal telemetry) TSP Telemetry ERCOT is concentrating its outreach efforts on helping to resolve remaining TSP telemetry issues in time to support Market Trials Phase 5.0 On the Feb 25 Outage Scheduler call, ERCOT reported >1200 TSP ICCP points unresolved TSPs have recently provided feedback on ~700 points Next steps include model cleanups and ownership assignments The TSP Telemetry Dashboard will refresh to the Readiness Center March 9, http://nodal.ercot.com/readiness/markettrials/rtm/index.html http://nodal.ercot.com/readiness/markettrials/rtm/index.html

8. http://nodal.ercot.com 8 Standing Reports and Updates: General reminders / updates Network Model Update –Load scheduled for 3/3/2010 completed successfully yesterday – Next 2 scheduled loads are 3/17/2010 and 3/31/2010 Follow-up from last weeks call: Q: Does a notification get sent to MPs in the cases of Late Actual Start and Late Actual End? A: No. To get the warnings the MP would need to send an ad-hoc get OutageSet request with a payload that has the warningFlagQuery element populated with true. This will return the outages that have a warning against them.

9. Qualification Update 43 / 86 QSEs are qualified (unchanged from last week) 5 / 20 TSPs qualified (unchanged from last week) 20 Business days left to complete Outage Scheduler Qualification The Outage Scheduler Qualification Dashboard –The dashboard will be updated ever Friday at 7pm http://nodal.ercot.com/readiness/markettrials/os/index.html http://nodal.ercot.com/readiness/markettrials/os/index.html http://nodal.ercot.com 9

10. http://nodal.ercot.com 10 Q&A Q&A / Open Forum

11. Appendix \ Appendix http://nodal.ercot.com 11

12. http://nodal.ercot.com 12 Environment Report: Changes to Supported Environment Hours Outage Scheduler Environment Availability for February - March 2010 –The Nodal Production Environment will be available Monday – Friday from 8am – 6pm –Outside of these hours, ERCOT will be executing performance testing and patch migrations based on testing results –For those MPs that provided ERCOT test certificates, there will be test notifications sent to your listeners (where applicable) during these internal ERCOT tests –ERCOT will coordinate with MPs when submitting to avoid qualification transactions Please note that only functionality that pertains to the Outage Scheduler qualification activities has been validated and are supported –Other features (such as reports and other MIS functionality) may be present in the environment but may have issues –ERCOT is still in the process of validating features to be released in later Market Trials Phases

13. http://nodal.ercot.com 13 Standing reports and updates: General Reminders / Updates ERCOT has published the Market Trials Phase 3 Handbooks –Outage Scheduler covering Phase 3.0 http://nodal.ercot.com/readiness/markettrials/os/index.htmlhttp://nodal.ercot.com/readiness/markettrials/os/index.html –Real Time Market / LFC covering Phase 3.0 http://nodal.ercot.com/readiness/markettrials/rtm/index.htmlhttp://nodal.ercot.com/readiness/markettrials/rtm/index.html –CRR covering release Phase 3.0 http://nodal.ercot.com/readiness/markettrials/crr/index.htmlhttp://nodal.ercot.com/readiness/markettrials/crr/index.html –Settlements / COMs covering Phase 3.0 http://nodal.ercot.com/readiness/markettrials/coms/index.htmlhttp://nodal.ercot.com/readiness/markettrials/coms/index.html –Day Ahead Market (note that this contains only reference data to the 2.1 qualification as there is no Phase 3.0 scope) http://nodal.ercot.com/readiness/markettrials/dam/index.htmlhttp://nodal.ercot.com/readiness/markettrials/dam/index.html