1. Lead from the front Texas Nodal http://nodal.ercot.com 1 Market Trials Call Bi-Weekly Update Sept 18, 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 Anti-trust Admonition Day-to-day operations summary –Planned and Unplanned ERCOT outages of Sandbox Standing reports and updates –General Reminders / Updates –SEM go-live update –Focused Input Testing Question and Answers/General Discussion Deep Dive Topic (different topics each meeting as needed) - No Deep Dive this Week 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. Lead from the front Texas Nodal http://nodal.ercot.com 4 Day-to-day operations summary: Planned / Unplanned Outages of EDS Planned Outages –No planned outages to report Unplanned Outages –No unplanned outages to report

5. Lead from the front Texas Nodal General Reminders / Updates Reminder: ERCOT is requesting test digital certificates issued by voluntary MP’s: –See appendix for details Reminder: Sandbox EIS1.19 available for testing –See appendix for details Reminder: Market Trials / MRS –Date / Time: 10/8 9:00am – 1:00pm –Austin Met Center Rm #206 –Agenda and presentation to be posted 10/2 to the ERCOT calendar: http://www.ercot.com/calendar/2009/10/20091008-EDS http://www.ercot.com/calendar/2009/10/20091008-EDS Reminder: Request for Updates to QSE Nodal Contact Information –See appendix for details

6. Lead from the front Texas Nodal General Reminders / Updates – EIS 1.19 Update ERCOT released an update to the EIS 1.19 and associated XSD’s on 9/10/09 –Changes to the XSDs as a result of defects found during integration testing –For full details, please refer to the updated EIS 1.19 specification and related XSDs The EIS 1.19 URL: http://nodal.ercot.com/readiness/sandbox/documents/index.htmlhttp://nodal.ercot.com/readiness/sandbox/documents/index.html XSDs URL: http://nodal.ercot.com/readiness/sandbox/websvc/index.htmlhttp://nodal.ercot.com/readiness/sandbox/websvc/index.html High Level Summary of changes are as follows: –ErcotCommonTypes.xsd: Changed the MWSingleDecimal regular expression field width to 4 Introduced TotalTmPoint to handle MarketInfo reports of total values which need no constraints Changed the ErcotPrice field width from 4 (9999.99) to 6 digits (999999.99) Added DSCM to the enumeration of Reason Code used in Three Part Offers BidSet –ErcotInformation.xsd Assigned TotalASSchedule to ASServicePlan and TotalASOffers simplified and allows large numbers –ErcotInformationTypes.xsd Added System parameters complex type Added TotalASSchedule using TotalTmPoint removing the input MW constraints to handle large numbers –ErcotForecast.xsd Corrected typo: WGRPP in type enumerations –ErcotAwards.xsd Added unbounded InsufficiencyReport container

7. Lead from the front Texas Nodal Technical Communications Workshop Synopsis – The technical communications workshop is designed to assist developers with the implementation of web service interfaces to the ERCOT Market Systems Target audience is developers and technical support personnel that are chartered with the implementation of web service interfaces to ERCOT The 2009 Technical Communications Workshop will take place on 10/28/09 –Currently this is scoped for a ½ day session –This duration may be extended based on the following: ERCOT will accept additional topics from MP’s (send topics to eds3@ercot.com)eds3@ercot.com MP’s will also be provided the opportunity to present on technical subjects as well (volunteer in advance) Current Agenda (High Level): –Setting up basic client (no security) –Implementing security –Setting up a listener –Maintenance –Special Topics (requested by Market Participants) To view and example of the detailed agenda (may vary year to year) view last year’s agenda / presentation here: http://www.ercot.com/calendar/2008/09/20080903-TCW http://www.ercot.com/calendar/2008/09/20080903-TCW

8. Lead from the front Texas Nodal http://nodal.ercot.com 8 SEM Go-Live Update SEM Go-Live for TSPs was Monday, Aug 31 8am ERCOT is applying NOMCRs to zonal production and nodal test systems TSPs verifying network model, and submit changes to ensure consistency and alignment of the model with TSP native systems. –Verification over next 5 months prior to integrated market trials Note that Network Model file is only available to TSPs –Model posting for QSEs discussion on agenda for NATF Sept 29 Agreement to discontinue weekly SEM market calls and work issues through NDSWG –Plan is for bi-weekly (every 2 weeks) NDSWG Web-Ex Objective to work and prioritize modeling issues and activities related to the SEM implementation

9. Lead from the front Texas Nodal 10/14/2015 http://nodal.ercot.com 9 This FIT Update includes the following discussion items:  Near-term FIT Windows  FIT III Week 15 Results  Nodal Telemetry Outreach Update  Convergence Trends (Running Results Summary for FIT III) Standing reports and updates: Focused Input Testing (FIT) Update

10. Lead from the front Texas Nodal http://nodal.ercot.com 10 FIT Update: Near-term FIT Windows Next FIT testing will take place 9/22 – 9/24 (see the Sept 17 Market Notice) Reminder: remaining FIT windows will only review telemetry and State Estimator convergence. The SCED inputs will be removed from FIT until further notice. The 2009 FIT Calendar is posted at: http://nodal.ercot.com/readiness/eds3/documents/r6/eds_3_lfc_fit3_calendar_20 09_v2.ppt http://nodal.ercot.com/readiness/eds3/documents/r6/eds_3_lfc_fit3_calendar_20 09_v2.ppt FIT III Assessment reports are posted at: http://nodal.ercot.com/readiness/eds3/documents/index.html http://nodal.ercot.com/readiness/eds3/documents/index.html ALL TIMES ARE CENTRAL DurationStart date and timeEnd date and time 27 hrs (3x9) Sept 22 - 8:00 AMSept 24 - 5:00 PM 27 hrs (3x9) October 6 - 8:00 AMOctober 8 - 5:00 PM 27 hrs (3x9) October 20 - 8:00 AMOctober 22 - 5:00 PM

11. Lead from the front Texas Nodal Key Numbers and Issues:  96% Test Average Convergence; 92% or higher for 26 of 27 Test Hours; 100% for 21 of 27 Test Hours. The majority of issues that arose during the test were attributable to Zonal-Nodal mismatches and missing Nodal telemetry.  On Sep 8, convergence started low at 23.08% for Hour Ending (HE) 0900 owing to bus mismatches, erroneous breaker statuses, and multiple telemetry issues that accumulated during the non-Business Hours preceding testing. During HE 1300, convergence dipped to 92.31% due to bad Nodal telemetry and mis-mapped SCADA points. ERCOT-side Manual Replacements (MRs) were made to correct these issues.  On Sep 9, convergence rates achieved 100% for all test hours, although ERCOT-side MRs were made throughout the test to adjust for missing Nodal telemetry, Zonal-Nodal mismatches, erroneous breaker status, and other telemetry issues.  On Sep 10, ERCOT discontinued MRs (see details on next slide). http://nodal.ercot.com 11 FIT Update: State Estimator - FIT III Week 15

12. Lead from the front Texas Nodal  On Sept 10, ERCOT discontinued ERCOT-side MRs for the first time during a FIT window.  The ERCOT State Estimator (SE) continued to solve during test hours with convergence rates comparable to those achieved during previous FIT windows.  Factors contributing to this success included:  Code enhancements that deployed to the Nodal production environment in August  ICCP updates that were recently submitted by Market Participants (MPs)  Robustness of the SE software http://nodal.ercot.com 12 FIT Update: State Estimator - FIT III Week 15 (continued) On Sept 10, ERCOT discontinued making MRs for Nodal telemetry  The SE convergence performance on Sept 10 promotes confidence that the software has matured to a point that ERCOT may continue to conduct future FIT windows without the need to facilitate SE solutions via ERCOT-side MRs.  The Sept 10 success may be seen as a good indicator of SE solution capability, but more work is needed in the area of measurement quality (see next slide).

13. Lead from the front Texas Nodal  To date, the outreach effort has focused primarily on Market Participants who are missing the largest share of ICCP points in Nodal.  ERCOT teams are now preparing to work with MPs to address a broader scope of missing points and clean-up issues.  The ERCOT Advanced Network Applications, ICCP, Client Services, and EDS teams have scheduled a series of weekly internal meetings through the end of 2009 to discuss outreach progress and to coordinate follow-ups with MPs.  As the outreach effort progresses, the quality of measurements used in each SE solution is expected to improve, along with overall confidence in SE solutions.  Information regarding the outreach effort and upcoming FIT windows will continue to be communicated via market notices, stakeholder meetings, and the regularly scheduled EDS market calls (http://www.ercot.com/committees/nodal/eds/).http://www.ercot.com/committees/nodal/eds/ http://nodal.ercot.com 13 FIT Update: Nodal Telemetry Outreach Update ERCOT began a Nodal Telemetry Outreach on August 31, 2009 to help MPs to correct Nodal telemetry issues in time for market trials. MPs may submit questions about the telemetry outreach to EDS3@ercot.com with “Nodal Telemetry Outreach” in the subject line.EDS3@ercot.com

14. Lead from the front Texas Nodal http://nodal.ercot.com 14 FIT Update: Current Telemetry Issue Process  For telemetry issues during FIT, contact a Shift Engineer at 512-248-6345.  For telemetry issues outside of FIT, contact EDS3@ercot.com.EDS3@ercot.com

15. Lead from the front Texas Nodal LFC10/14/2015 FIT Update: High-Level View of the ICCP Change Process 15 The TML process for QSE ICCP Service Requests and an example of the ICCP Change Request Form are posted at: http://nodal.ercot.com/readiness/eds1/documents/index.html

16. Lead from the front Texas Nodal LFC10/14/2015 FIT Series WeekDateDay 1Day 2Day 3Convergence Avg % for all Test Hours 100% Convergence Achieved FIT IIIWeek 1Feb 24 – 26, 200975.4578.8692.8582.3909 of 27 hrs Week 2Mar 10 – 12, 200996.8292.9798.4196.0720 of 27 hrs Week 3Mar 24 - 26, 200985.4594.9894.7091.7114 of 27 hrs Week 4Apr 07 - 09, 200997.1392.6097.4495.7221 of 27 hrs Week 5Apr 21 – 23, 200987.4789.8795.6591.0008 of 27 hrs Week 6May 05 – 07, 200994.3494.4791.8793.5613 of 27 hrs Week 7May 19 – 21, 200996.8197.3697.0497.0718 of 26 hrs* Week 8Jun 02 – 04, 200988.4784.0993.2988.6210 of 27 hrs Week 9Jun 16 – 18, 200997.4586.1495.5993.0613 of 27 hrs Week 10Jun 30 – Jul 2, 200994.9189.8986.6690.4911 of 27 hrs Week 11Jul 14 – 16, 200991.0184.7097.4991.0614 of 27 hrs Week 12Jul 28 – 30, 200995.9194.7393.6694.7718 of 27 hrs Week 13Aug 11 – 13, 200994.7294.6597.3795.5819 of 27 hrs Week 14Aug 25 – 27, 200996.5193.2599.0796.2821 of 27 hrs Week 15Sep 08 – 10, 200990.6010096.3395.6421 of 27 hrs FIT Update: Convergence Trends – FIT III 16 * One hour was removed from the Week 7 test results to accommodate a nodal database load.

17. Lead from the front Texas Nodal http://nodal.ercot.com 17 Q&A Q&A / Open Forum

18. Lead from the front Texas Nodal http://nodal.ercot.com 18 Appendix

19. Lead from the front Texas Nodal http://nodal.ercot.com 19 Telemetry Issue Resolution and ICCP Change Process (originally presented 9/18/09)

20. Lead from the front Texas Nodal http://nodal.ercot.com 20 FIT Update: Current Telemetry Issue Process  For telemetry issues during FIT, contact a Shift Engineer at 512-248-6345.  For telemetry issues outside of FIT, contact EDS3@ercot.com.EDS3@ercot.com

21. Lead from the front Texas Nodal LFC10/14/2015 FIT Update: High-Level View of the ICCP Change Process 21 The TML process for QSE ICCP Service Requests and an example of the ICCP Change Request Form are posted at: http://nodal.ercot.com/readiness/eds1/documents/index.html

22. Lead from the front Texas Nodal http://nodal.ercot.com 22 QSE Information Update Request (originally presented 9/04/09)

23. Lead from the front Texas Nodal QSE Information Update Request As we near Market Trials, ERCOT is asking that all QSE’s and TSP’s update needed information Each MP will receive an email by the end of next week directing them to the attached spreadsheet The spreadsheet will have inputs for the following: –Primary / Back-up contact information for each of the functional areas (e.g. DAM, RTM, ICCP, Settlements, CRR….), Accountable Executive, Authorized Rep and Nodal Project Manager We ask that at least 1 back-up be provided for each area There is space to add up to 3 back-ups –Listener URL for notifications sent from ERCOT to MP’s (this is to confirm what we already have on file is correct) –Email address where notification failure alerts will be sent

24. Lead from the front Texas Nodal http://nodal.ercot.com 24 ERCOT Certificate Request (originally presented 9/04/09)

25. Lead from the front Texas Nodal ERCOT Certificate Request ERCOT is requesting test digital certificates issued by voluntary MP’s: –Agenda and presentation to be posted 10/2 to the ERCOT calendar: http://www.ercot.com/calendar/2009/10/20091008-EDS http://www.ercot.com/calendar/2009/10/20091008-EDS –Aug 27, 2009 ERCOT released all nodal roles to the production MPIM (Market Participant Identity Management) –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. –NEW: This user should have the “web services” checkbox checked when creating the 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 by October 1, 2009

26. Lead from the front Texas Nodal http://nodal.ercot.com 26 NODALTEST Certificates Expiration (originally presented 8/07/09)

27. Lead from the front Texas Nodal Standing reports and updates: Certificates (reminder) NODALTEST Certificate Expirations –All NODALTEST certificates will expire over the next several months –These certificates will not be renewed –In order to continue to test in the sandbox, MP’s may use any valid ERCOT certificate –When the Nodal Production environment is deployed in October, MP’s will use their current (zonal) certificate. –MP USA’s will need to add the appropriate Nodal roles depending on the testing that user will perform –Note: Nodal roles will not have an affect on zonal system usage

28. Lead from the front Texas Nodal http://nodal.ercot.com 28 Creation of the Nodal Implementation Team (originally presented 6/12/09)

29. Lead from the front Texas Nodal Standing reports and updates Program Update – Creation of the Nodal Implementation Team (NIT) –At its June 4, 2009 meeting, TAC created the Nodal Implementation Team (NIT) which will be a vehicle for stakeholder engagement in the Nodal program. –In preparation for the NIT initial meeting, the TPTF email distribution list has been discontinued and has been replaced by the NIT distribution list (NIT@lists.ercot.com)NIT@lists.ercot.com If you were previously subscribed to the TPTF distribution list, no action is needed as TPTF subscribers were automatically migrated to the NIT distribution list. If you were not previously subscribed to the TPTF distribution list and would like to subscribe to the NIT distribution list, please access the ERCOT distribution list management website at http://lists.ercot.comhttp://lists.ercot.com –Meeting materials, agenda, and WebEx information will be distributed as soon as they are available –First Meeting will take place on Monday, June 22, 2009 9:30 am – 4:30 pm –The NIT Charter was distributed via email to NIT@lists.ercot.comNIT@lists.ercot.com The charter is embedded below for your review:

30. Lead from the front Texas Nodal http://nodal.ercot.com 30 Review of Overall Registration Data Project Schedule (originally presented 5/22/09)

31. Lead from the front Texas Nodal http://nodal.ercot.com 31 Review of Overall Registration Data Project Schedule http://nodal.ercot.com 31 Each window will be broken into 3 iterations with heightening levels of data quality goals All non-PUN RE’s will submit during 1 of 2 windows (except Wind) Each non-PUN RE will request one of the two windows between 5/22/09 and 6/5/09 via email to nodalmarkettransition@ercot.comnodalmarkettransition@ercot.com Some RE’s may be moved to a different window based on volume Planning and Protection data will be rolled in for the remaining windows (see next slide) All Wind resources will submit during the second window 2009 MAR APR MAY JUN JUL AUG SEP OCT NOV DEC Private Use Network Transmission Data Collection Window 1 - Non-Wind* RE’s 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 Window 2 - Wind RE’s Transmission and Planning / Protection Data Collection - Iteration 1 - Iteration 2 - Iteration 3 MP-10 Phase 2 Final Validation SEM GO-LIVE 8/31 EIS 1.19 to EDS 8/10 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

32. Lead from the front Texas Nodal Registration Data Collection Update Iteration 3 of the Private Use Network Transmission Data Collection closes on 5/19/09 Current Production Quality Metric is 96.5% (goal is 98% by 5/19) 5/22/09 9:30AM – 11:00AM ERCOT will host a kick off for the next leg of the Nodal Registration Data Collection project Changes to Load Resource Registration The kick off meeting will cover the following topics: –Transmission data collection (review for non-PUNs / non-Wind) –Planning and Protection data review (inclusive of Private Use Networks) –Review of registration activities for the remainder of 2009

33. Lead from the front Texas Nodal http://nodal.ercot.com 33 Nodal API sub-group Report, by Transaction, Completion Confidence (originally presented on 2/6/09)

34. Lead from the front Texas Nodal http://nodal.ercot.com 34 Standing reports and updates: Nodal API sub-group (originally presented on 2/6/09) TPTF Action – Report, by Transaction, Completion Confidence –Each Transaction will be classified into 3 confidence levels –RED – Confidence low – high risk of change in the 1.18 and/or 1.19 releases –YELLOW – Changes should be limited to non-structural changes (e.g. enumeration changes) –GREEN – Any Changes will be limited to defects. –Note that if there are no changes in 1.18 and significant change in 1.19, a transaction will be marked as RED for both. It will retain that color until all changes are complete.

35. Lead from the front Texas Nodal http://nodal.ercot.com 35 Standing reports and updates: Nodal API sub-group (originally presented on 2/6/09)

36. Lead from the front Texas Nodal http://nodal.ercot.com 36 Standing reports and updates: Nodal API sub-group (originally presented on 2/6/09)

37. Lead from the front Texas Nodal http://nodal.ercot.com 37 Verifiable Cost Submission (originally presented on 4/17/09)

38. Lead from the front Texas Nodal http://nodal.ercot.com 38 Verifiable Cost Submission (originally presented on 4/17) WMS Approved Verifiable Cost Submission Timelines: Simple Cycle Greater than 90MW June 30, 2009 Simple Cycle Less than or Equal to 90MW July 31, 2009 Gas Steam Non-Reheat Boiler Aug 31, 2009 Gas Steam Reheat BoilerSep 30, 2009 Gas Steam Super Critical BoilerOct 31, 2009 Combined Cycle Less than or Equal to 90MW Nov 30, 2009 Combined Cycle Greater than 90MW Dec 31, 2009 Coal, Lignite Jan 31, 2010 Nuclear, Hydro and Renewable Feb 28, 2010 Reciprocating Engines Feb 28, 2010

39. Lead from the front Texas Nodal http://nodal.ercot.com 39 Verifiable Cost Submission ERCOT plans to roll out verifiable cost training: Verifiable Cost Training will cover: –What are Verifiable Costs –What data need to be submitted –Who is required to submit the data forms and supporting information –Where, when and how are Verifiable Costs used Current Plans: –Instructor Led Training during May/June –One session each in Austin, Houston and Dallas Please send any comment to nodaltraining@ercot.comnodaltraining@ercot.com