1. April 1, 2008 TPTF Early Delivery Systems Status Daryl Cote

2. 2 2 TPTF4/1/2008 Agenda EDS 2 –Release 3: State Estimator TSP Dashboard Load Status Wind QSE Dashboard SE results (March vs Feb) –EDS 2 Release 4: NOMCR EDS 3 –Release 5: SCED –Release 6: LFC –Release 7: CRR EDS 4 –Release 8: Coms –Release 9: DAM / RUC / SASM

3. 3 3 TPTF4/1/2008 TSP Dashboard

4. 4 4 TPTF4/1/2008 Convergence Rate MVAR tolerance remains at 30. Working to identify reactive curves that need to be adjusted so that MVAR can be set to 15 also

5. 5 5 TPTF4/1/2008 Load Status

6. 6 6 TPTF4/1/2008 EDS 2 – Wind Output from QSEs This data is required to support AWS TrueWind’s forecast tuning

7. 7 7 TPTF4/1/2008 QSE Dashboard

8. 8 8 TPTF4/1/2008 State Estimator 30 day Comparison Metric Zonal 2-28 Zonal 3-27 Nodal 2-28 Nodal 3-27 Buss Observability 98.198.094.795.3 Branch with MW measurement mismatches across 2 ends Line Only Line >5748189104 Line >1514172925 Line >2534149 Max68.738.4-219.4-98.1

9. 9 9 TPTF4/1/2008 State Estimator 30 day Comparison II Measurement Availability Zonal 2-28 Zonal 3-27 Nodal 2-28 Nodal 3-27 Analog Measurements Available Mapped-Non SI% 95.595.988.690.0 Topology Monitoring Unit Forced Remove 323427 Load Forced Remove 14162234

10. 10 TPTF4/1/2008 Next Steps Complete Telemetry Reporting Remedy Application issues ERCOT build redundant servers at Met Center

11. 11 TPTF4/1/2008 Release 4 – NMMS / NOMCR 2007 2008 SepOctNovDecJan Feb R4: NOMCR / Network Model verification E2 R4 NOMCR Checkout Network Model Verification  NMMS/NOMCR overview training has been completed by the market participants  Citrix connections and digital certificates have been successfully installed and validated for 100% of the market participants  Onsite NMMS training and scripted scenario execution completed by:  AEP, Rayburn, STEC, and College Station  Onsite training to occur week of 4/7 for:  CenterPoint & Greenville  Onsite training to occur week of 4/14 for:  Austin Energy, Garland, CPS San Antonio  All MP to complete onsite training week of 5/19

12. 12 TPTF4/1/2008 EDS SLA Metrics This data only describes HW. March number should include applications. Reports are posted at: http://nodal.ercot.com/readiness/index.html EDS - SLA Metrics Summary (February 2008) http://nodal.ercot.com/readiness/index.htmlEDS - SLA Metrics Summary (February 2008)

13. 13 TPTF4/1/2008 Release 5 - SCED 2007 2008 SCED R5.1SCED R5.3: RT ICCPSCED R5.4: LMP Post SepOctNovDecJan Feb SCED R5.2 E3 R5 6-month LMP Posting RT ICCP EDS 3 Release 5 Exit Criteria % Complete Comments Daily submissions of COP, TPO, and OS~90%Temporary performance fix to be included in MMS3 Average submissions are in the 90% range Issue encountered with MMS caused outage from 3/19 to 3/26; SPPs still not being published Upgrade of EMS broke EMS – MMS; resolved on 3/26 SCED Inputs verified: HRL, LRL, SURAMP, SDRAMP, HDL, LDL; GTBD, ICCP 90% (80%) GTBD within ~200 MW of Zonal SCED Outputs verified: QSE’s ability to receive Resource Base Points and LMPs via ICCP 90% (60%) Base Point and LMPs (with 5 decimals being sent over ICCP) Base Point and LMP calculation verified for Resources with Offer Curves or Output Schedules 100% (100%) Reports100% (100%) Reports related to SCED are available in draft form on MIS and https://nodaleds.ercot.com/nodalercot/readiness/reports/publicreports.htm l https://nodaleds.ercot.com/nodalercot/readiness/reports/publicreports.htm l LMPs verified for Reasonability and posted to MIS for Market Participant review100% (100%) Completed on Feb 15 th. The calculation of the LMPs are reasonable given the input data, but the input data needs improvement. Legend: % in parentheses are from the 2/22 TPTF update

14. 14 TPTF4/1/2008 Recent Issues with LMPs Poor quality of ICCP data will cause SE & TCM to not publish results to MMS; therefore stale LMPs & BPs or uniform LMPs EMS – MMS interface shuts down daily (reported Oracle issue); therefore stale LMPs & BPs COP / TPO / OS submissions to SCED are sufficient EMSMMS Market Participant Starting in Mid-April, ERCOT will contact MPs Real-Time desks when data issues cause SE / TCM failures. This will be done 24x7 1 2 3 1 2 3

15. 15 TPTF4/1/2008 Release 6 - LFC 2008 JanFebMarAprMay Jun E3 R6 R6.1: ACE & RLC EDS 3 Release 6.1 Exit Criteria % CompleteComments Test Time Scheduled (Phase 1 and 2)100% (100%) Dates have been set with all QSEs with Resources. Completed Test Form Received back from MP100% (80%) All QSEs tested RLC Validation Completed100% (71%) Full completion pending regression test of SPR 1643 and 2211 Emergency Base-Point Validation Completed100% (33%) ERCOT issue has been resolved and QSEs that conducted testing when the issue existed have been contacted to setup a regression test EM05 verify ACE PerformanceTBD% (0%) Data submitted to TPTF for review Legend: % in parentheses are from the 2/22 TPTF update R6.2: QSE TestingR6.3: TST

16. 16 TPTF4/1/2008 Release 6 - LFC 2008 JanFebMarAprMay Jun E3 R6 R6.1: ACE & RLC EDS 3 Release 6.2 Exit Criteria % CompleteComments Testing time scheduled100% (0%) 6.2 pre-test conducted (dry-run)20% (0%) Garland P&L, NRG, STEC, Suez Individual QSE UDBP and Regulation10% (0%) Garland P&L, STEC Constant Frequency Operation Test10% (33%) Garland P&L, STEC Responsive Reserve Service Schedule Test10% (0%) Garland P&L, STEC Legend: % in parentheses are from the 2/22 TPTF update R6.2: QSE TestingR6.3: TST ~ 50% of the AS schedules and responsibilities being provided accurately via ICCP. 6.3 testing can not commence without this data. QSEs wishing to accelerate their 6.2 test date are encouraged to do so.

17. 17 TPTF4/1/2008 LFC 6.3 pre-Test Prior to R6.3 (total system test) the market desires an open loop test to validate SCED dispatch. Approach to accomplish this: –QSEs w/ Resources submit Excel files with EOC, OS, INC/DEC on 4/8 that deconstruct Zonal activities for Operating period 4/7 7-9am –Perform open loop test on 4/25 from 7-9am –Perform open loop test on 5/5 from 10-noon –Perform open loop test on 4/12 from 4-6pm ERCOT to provide QSEs with settlement impact resulting from OOME and Local Balancing had units followed SCEB BP Please refer to details provided during the 3/14 workshop: http://www.ercot.com/calendar/2008/03/20080314-EDS3-6.html http://www.ercot.com/calendar/2008/03/20080314-EDS3-6.html

18. 18 TPTF4/1/2008 Target Dates for 6.3 Tests Week of June 16 th – 2 hour test Week of July 7 th – 8 hour test Week of July 28 th – 48 hour test

19. 19 TPTF4/1/2008 Release 7 - CRR EDS 3 Release 7 Status% CompleteComments Release 7.1 Connectivity and Submissions100% (0%) 56 of 71 completed tests Release 7.2 Scripted Monthly Auction100% (0%) 50 participants successfully submitted bids (91% participation) Release 7.3 unscripted Monthly Auction100% (0%) 40 participants successfully submitted CRR Market Credit Limit (71% participation) 43 participants successfully submitted self-created bid portfolios (75% participation) 39 participants participated in bilateral trade activity – initiated or accepted trades (69.64% participation) Readiness Metric CRR3 Completed Jan 08Feb 08Mar 08Apr 08May 08Dec 07 CRR–R7.0CRR–R7.1CRR–R7.2CRR–R7.3 CRRR7.4 CRR–R7.5 (TBD) Jan 08Feb 08Mar 08Apr 08May 08Dec 07Jan 08Feb 08Mar 08 Apr 08 May 08Dec 07 CRR–R7.0CRR–R7.1CRR–R7.2CRR–R7.3CRR–R7.5 (TBD) Release 7.4 Scheduled to begin 4/7; possibility of delayed completion CRR team to discuss configuration limitations with TPTF on 4/2 Legend: % in parentheses are from the 2/22 TPTF update

20. 20 TPTF4/1/2008 EDS 4 Release 9.1 2008 JanFebMarAprMay Jun E4 R9 R9.1: DAM/RUC Submission TestingR9.3:R9.4: DAM/ Adj Period, RT R9.2: Outage Scheduler Legend: % in parentheses are from the 2/22 TPTF update Those not completed with 9.1 will be Red for Readiness Metric MP8 after 3/31. EDS 4 Release 9.1 Exit Criteria% Complete Comments Intent to Participate Sent86% (83%) Sign-Up Testing Window Scheduled86% (81%) See next slide MP8 - QSE Ability to Submit Transactions Via MIS 86% (32%) MP9 – QSE Ability to Submit Web Service Transactions 100% (23%) Of those who indicated desire to use Web Services

21. 21 TPTF4/1/2008 EDS 4 Release 9.1 Ambridge Energy* Aquila Citadel Energy Products Clearview Electric Glacial Energy Kansas City Power and Light National Power Company Sitara Energy Texpo Power Urban Energy Source WCW International QSEs that have not signed up for a testing window for EDS4 (as of COB 3/28/08)

22. 22 TPTF4/1/2008 EDS 4 Release 9.2 2008 JanFebMarAprMay Jun E4 R9 R9.1: DAM/RUC Submission TestingR9.3:R9.4: DAM/ Adj Period, RT R9.2: Outage Scheduler Legend: % in parentheses are from the 2/22 TPTF update Release 9.2 Kickoff webex conducted on 3/27 Testing to occur from 4/15 through 6/13 EDS 4 Release 9.2 Exit Criteria% Complete Comments Test Window ScheduledMarket notice sent requesting TSPs and QSEs with Resources schedule a test window by 4/4. 10 MPs have responded to date (as of 3/31) Completed Scripted Testing Participate in Performance testing Participate in Dual Entry days (prior to 168hr test)

23. 23 TPTF4/1/2008 EDS 4 Release 9 timeline as showed in the approved handbook FebMarAprMayJunJulJanAug 9.1 - DAM/RUC Submission testing 9.3 - Initial DAM/RUC Exec 9.4 - Exec DAM, Adj Period, RT Ops 9.5 - Pre-Test for 168 hour test Final assembly and testing of all deliveries, integration and functionality Implement final MMS delivery to include Baseline 1 and 2 changes Testing of relevant portions of MIS/EDW/Extracts Test of EECP, DST, Compliance monitoring and tools Execute DAM without any significant error of DAM for 7 consecutive days and provide settlement statements Execute two Operating Days without interruption along the full market timeline with no critical failures ERCOT and QSEs execute nodal timeline in parallel to zonal market Begin Adj Period activities – SASM/HRUC Submit all transactions for DAM, Adj Period and RT Ops Download reports for DAM/DRUC/HRUC/SASM Performance testing of DAM Stub data as needed for DAM, Adj Period and RT activities Execute market timeline for 7 consecutive days QSEs submit transactions to DAM/RUC Post pre-DAM/RUC exec data (A/S Obligations, LF) Execute DAM and RUC Test MMS integration with NMMS and EMS Communicate results to QSEs (MIS and notifications) Test QSE ability to receive notifications, prices, awards Stub in other data as needed DAM/RUC database for MP EDS Activities Verify QSEs ability to submit, modify, cancel, and retrieve submission items using MIS/User Interface and/or Web Services MMS2 DAM / RUC Submission Items MMS2 CIM Integration EMS-MMS Integration MMS3 (MMS2 + SASM, CIM Imp) MMS4 Settlements integration All Integration points addressed MIS/EDW Integration

24. 24 TPTF4/1/2008 Proposed revisions to EDS 4 Release 9 timeline FebMarAprMayJunJulJanAug 9.1 - DAM/RUC Submission testing 9.3 - Exec DAM/RUC/SASM 9.4 – Integration and Preparation for 168 hour test Final assembly and testing of all deliveries, integration and functionality Implement final MMS delivery to include Baseline 1 and 2 changes Performance testing of DAM Execute DAM, DRUC, HRUC, SASM CIM Integration between NMMS, MMS and EMS Test of EECP, DST, Compliance monitoring and tools Testing of relevant portions of MIS/EDW/Extracts Execute DAM without any significant error of DAM for 7 consecutive days and provide settlement statement Execute two Operating Days without interruption along the full market timeline with no critical failures ERCOT and QSEs execute nodal timeline in parallel to zonal market DAM/RUC database for MP EDS Activities Verify QSEs ability to submit, modify, cancel, and retrieve submission items using MIS/User Interface and/or Web Services QSEs submit transactions to DAM/RUC Post pre-DAM/RUC exec data (A/S Obligations, LF) Execute DAM and RUC Communicate results to QSEs Test QSE ability to receive notifications, prices, awards Stub in other data as needed Execute SASM/HRUC capabilities in May 08 MMS2 DAM / RUC Submission Items MMS3 CIM Data Stub MMS4 Settlements integration All Integration points addressed MIS/EDW Integration MMS 3 and MMS 4 will be deployed earlier to the EDS environment to enable market testing

25. 25 TPTF4/1/2008 What does it mean for ERCOT and MPs FebMarAprMayJunJulJanAug 9.1 - DAM/RUC Submission testing 9.3 - Exec DAM/RUC/SASM 9.4 – Integration and Preparation for 168 hour test MMS2 EIP MMS UI MMS 3 Stub CIM + other data EIP Awards query MMS UI upgrades MMS 3 EIP Notifications UI Notifications MMS-OS Integration EMS-NMMS-MMS Integration Implement last EMS delivery MMS-CMM integration MIS CDR Compliance monitoring Submit, modify, retrieve, cancel bids and offers Submit transactions to DAM and RUC Download DAM Awards Participate in DAM, Adj period and RT Ops testing Receive DAM Award notifications Validate Settlements stmts Participate in DAM performance test Verify new Day Ahead and RT reports Extract support Adapt to Baseline1/2 Market Submission changes in MMS4 Participate in DAM and settlement of 168 hour test Participate in DST and Failover testing Participate in EECP test Provide environment for uploading bids and offers Execute DAM / RUC Enable downloads of awards Produce DAM settlement stmts Execute DAM / RUC/HRUC/SASM Produce DAM settlement stmts Enable notifications Conduct DAM performance test Run market timeline for 7 consecutive days Conduct 168 hour test of DAM EECP DST and Failover Compliance monitoring MMS 4 EMS-MMS Integration MMS - S&B Integration MMS - NMMS integration CSI Execute DAM / RUC/HRUC/SASM Implement B1 & B2 submission items Settlements Integration Current day reports and EDW extracts will be deployed according to the DAG schedule ERCOT Market Participant

26. 26 TPTF4/1/2008 A Go-Live Plan is being developed that will encompass key activities/actions post the successful completion of the 168-Hr test Key Elements of the plan include:  ERCOT and Market Participant engagement expectations  Communications and ongoing health checks during the go-live period  Phased staging of production submission during cut-over  Planned regression test of Nodal LFC  Software environment controls (migration freeze)  Contingency planning and guidelines for switch of control back to zonal Next StepsTarget Completion Date Complete ERCOT reviewApril 7 th Present to TPTF for VoteMay 5 th Present to TAC for VoteJune 5 th Present to BoDJune 17 th

27. 27 TPTF4/1/2008 EDS Deliverables DAM/RUC R9.4 EECPGo-LiveDST Post for TPTF Comment Apr 25Apr 7April 10May 8 Comment CloseMay 1Apr 14April 24May 16 TPTF VoteMay 5Apr 21May 5May 22/23 Legend: indicates completion

28. 28 TPTF4/1/2008 Questions?