1. October 22, 2007 TPTF Meeting Early Delivery Systems Status Update and Forecast Daryl Cote/John Webb/John Hall

2. 2 2 Texas Nodal Program UpdateOctober 22, 2007 EDS Status Update 2007 2008 SCED R5.1SCED R5.3: RT ICCPSCED R5.4: LMP Post SepOctNovDecJan Feb SCED R5.2 ICCP Fail-over / P2P R3: SE / Telemetry Criteria (SE Tuning) R4: NOMCR / Network Model verification E1 R2 E2 R3 E2 R4 E3 R5 E3 R6 LFC R6.1: ACE E3 R7 CRR R7.1 E4 R9 R9 6-month LMP Posting SE Verification RT ICCP NOMCR Checkout Network Model Verification EDS 1 Exit Criteria % of MPs % of Points Comments MPs have completed PtP checkout and topology review for all submitted Nodal points 87% (85%) 97% (97%)  33 of 38 MPs tested. 99% completion projected to Oct 31 th.  1 QSE will ‘work-around’ to provide ICCP during October. Final test by mid-Nov (~500 pts).  Risk - coordination and modeling of SGR and CC units. ERCOT has completed local failover testing with each MP82% (74%) n/a  31 of 38 tested. 2 to complete by Oct 31 st.  2 MP will test in November and 3 in December ERCOT has completed Alarm Processing configuration and testingn/a80%  Alarm processing testing will be completed once all PtP testing is completed. ERCOT has completed all PtP process documentation to support checkout for new construction / future changes to telemetry 90%  Final process handoff and transition to Operations planned for November. Outstanding ICCP issues <= 3% per MP79% (82%) n/a  Overall error rate ~2%.  26 of 33 MP tested are at or below 3% error rate.  Last report was a reporting error. Quality Code Retesting32% (0%) n/a  Quality Code migrated to EDS on 9/29  12 MPs regression tested with quality code fix Reporting Legend: % in parentheses are from the last update

3. 3 3 Texas Nodal Program UpdateOctober 22, 2007 R4: NOMCR / Network Model verification EDS Status Update 2007 2008 SCED R5.1SCED R5.3: RT ICCPSCED R5.4: LMP Post SepOctNovDecJan Feb SCED R5.2 ICCP Fail-over / P2P R3: SE / Telemetry Criteria (SE Tuning) E1 R2 E2 R3 E2 R4 E3 R5 E3 R6 LFC R6.1: ACE E3 R7 CRR R7.1 E4 R9 R9 6-month LMP Posting SE Verification RT ICCP NOMCR Checkout Network Model Verification EDS 2 Release 3 Exit Criteria % Complete Comments TSP/QSE data points reasonably conform to Telemetry and SE Performance criteria 0% All QSEs that completed p2p are providing real-time feeds. Working with LCRA to request calculated points vs. new telemetry. Dependant on EDS1 p2p, issues resolution, quality code patch. SGR/CC unit issues remain to be modeled/mapped by ERCOT. ERCOT Operations have operating procedures in place to address performance issues 30% (30%) 8 of 27 procedures have been updated. The remaining will be completed when Release 3 processes are verified. Network Security Analysis functions are verified and ERCOT Operations have procedures in place to manage 76% (30%) SE STAT is 90% tested; Contingency Analysis is 95% tested; Dynamic Ratings is 30% tested; RTMONI is 90% tested ERCOT SE is tuned and meets performance criteria15% (10%) SE is solving but requires real time data feeds Load Modeling restructured, load adaptation and bus load forecast verified 20% (20%) Scheduled to begin 10/31. Progress result of work in FAT environment EDW reports correctly post to MIS and can be accessed0%SE Performance reports are completing FAT testing. Telemetry reports will be provided using a workaround until early 2008. EDW reports have been verified within ERCOT and by MPs0%Telemetry and State Estimator standards in approval process. Reporting Legend: % in parentheses are from the last update

4. 4 4 Texas Nodal Program UpdateOctober 22, 2007 EDS Status Update 2007 2008 SCED R5.1SCED R5.3: RT ICCPSCED R5.4: LMP Post SepOctNovDecJan Feb SCED R5.2 ICCP Fail-over / P2P R3: SE / Telemetry Criteria (SE Tuning) R4: NOMCR / Network Model verification E1 R2 E2 R3 E2 R4 E3 R5 E3 R6 LFC R6.1: ACE E3 R7 CRR R7.1 R9 6-month LMP Posting SE Verification RT ICCP NOMCR Checkout Network Model Verification EDS 2 Release 4 Entry Criteria % Complete Comments NMMS Phase 1C has completed FAT Testing0%Pre-FAT stopped due to critical bugs, # of issues during ERCOT model load substantially reduced MIS/NMMS link has completed ITest and is installed in EDS25% (25%) Currently testing Citrix connection at ERCOT and security layer to MIS. Scheduled completion on 10/15 NMMS is installed in EDS0% EMS Nodal Importer has completed ITest and is installed in EDS0%Scheduled for a February 2008 release into the EDS environment; will not migrate until MMS importer also available NMMS database has been successfully loaded with: ERCOT NOM database; ICCP modeling point database; Ownership / operatorship data 0%Currently working with TSPs/MPs (and ERCOT working groups) on data information for loading. Waiting on NMMS Phase 1C delivery to install and configure data NMMS database is placed under full change control0%Once data is loaded and verified by MPs, DB will be under ERCOT change control. Reporting Revised start date is Nov 12 th Legend: % in parentheses are from the last update

5. 5 5 Texas Nodal Program UpdateOctober 22, 2007 EDS Status Update 2007 2008 SCED R5.1SCED R5.3: RT ICCPSCED R5.4: LMP Post SepOctNovDecJan Feb SCED R5.2 ICCP Fail-over / P2P R3: SE / Telemetry Criteria (SE Tuning) R4: NOMCR / Network Model verification E1 R2 E2 R3 E2 R4 E3 R5 E3 R6 LFC R6.1: ACE E3 R7 CRR R7.1 E4 R9 R9 6-month LMP Posting SE Verification RT ICCP NOMCR Checkout Network Model Verification EDS 3 Release 5 Exit Criteria % Complete Comments QSEs w/ Resources able to submit COP, TPO, OS, INC/DEC100% (100%) MP2 100% & MP3 100% for SCED R5.1 testing. Completed on 10/1. R5.2: 64% of COPS submitted; 57% of TPO submitted SCED Inputs verified: HRL, LRL, SURAMP, SDRAMP, HDL, LDL; GTBD, ICCP 0%Expected to be operational in EDS Nov 1 st SCED Outputs verified: QSE’s ability to receive Resource Base Points and LMPs via ICCP 0%Verifications to begin November 1 st. ICCP Data being confirmed (e.g. Hub & Load Zone LMPs vs just generation specific LMPs) Base Point and LMP calculation verified for Resources with Offer Curves or Output Schedules 0%Verifications to begin November 1 st. Reports0%Preliminary reports to be available Nov 1 st : See next slide Remaining reports by 11/15: see next slide LMPs verified for Reasonability and posted to MIS for Market Participant review0% Reasonableness criteria to be communicated in SCED Handbook R5.3 Reporting Legend: % in parentheses are from the last update EMS – MMS interface migrated to EDS for testing to support R5.3 start. Resolving data issues

6. 6 6 Texas Nodal Program UpdateOctober 22, 2007 SCED Reports – Expected Delivery Schedule Expected Delivery Nov 1 st –LMPs on Resource Nodes –SPPs on each hub and load zone –Shadow Prices –Binding transmission constraints Expected Delivery Nov 15 th –15 min avg. of Loads on Electrical Buses –Status of breakers and switches –Transmission flows and voltages –Transformer flows, voltages and tap position –Voltage schedule Sample reports posted to Nodal Readiness Center for Nov 1 st reports. Mock Data used for sample reports.

7. 7 7 Texas Nodal Program UpdateOctober 22, 2007 EDS Deliverables CRR Handbook LFC Handbook SCED handbook (R5.2) SCED handbook (R5.3)* Initial Review (EDS workshop / WebEx / TPTF) 8/279/12 10/10 8/28 Post for TPTF8/279/289/1410/12 TPTF Vote9/2510/229/2510/22 *R5.4 was not updated in the SCED handbook as previously communicated. Expect to publish that in early November. We still expect to publish the EDS 4 Testing Approach in early November Legend: indicates completion

8. 8 8 Texas Nodal Program UpdateOctober 22, 2007 MP Activities TSPs: –Confirm Electrical Buses, SPPs, etc. –Register for NOMCR training / testing Developing training curriculum and will distribute – notice was held until a revised start date could be estimated –Local ICCP failover test (Now) QSEs with Resources –Submit SCED inputs via web services for your entire portfolio (now) –Ensure your Nodal ICCP feed is operational (Now) Start providing new ‘Nodal ICCP’ points –Local ICCP failover test (Now) –Validate Resource specific Base Points and LMPs (Nov ‘07) –Use Nodal Sandbox for next set of web services (Now)

9. 9 9 Texas Nodal Program UpdateOctober 22, 2007 MP Activities (cont.) QSEs without Resources –Validate your application against new web services (Now) CRR Account Holders –Complete registration forms to participate in CRR testing activities NOIE - Dec 1 st ’07 (PCRRs) WGRs – Dec 1 st 07 (MCFRIs) CRR Account Holder – Jan 15, 2008 NOIEs –Notify ERCOT of their intention to establish a NOIE Load Zone for Early Delivery System (EDS) testing purposes only – Dec 1 2007