1. ROS Meeting – 05/15/081Texas Nodal Program - TPTF Update Texas Nodal Transition Plan Task Force ROS Meeting Stacy Bridges, ERCOT Thursday, 05/15/08

2. ROS Meeting – 05/15/082Texas Nodal Program - TPTF Update Last month at TPTF / April 2008 During April 2008, TPTF met on:  March 31 – April 2 March 31 – April 2  April 21 – 22 April 21 – 22

3. ROS Meeting – 05/15/083Texas Nodal Program - TPTF Update Last month at TPTF / April 2008 Major Accomplishments / March 31 – April 2, 2008March 31 – April 2, 2008  Endorsement of NPRRs:  On April 1, TPTF endorsed the following NPRRs to synchronize Zonal Protocols:  NPRR105, Section 23, Texas Test Plan Team – Retail Market Testing NPRR105  NPRR106, Section 24, Retail Point-to-Point Communications NPRR106  NPRR109, Section 18, Load Profiling NPRR109  NPRR110, Section 20, Alternative Dispute Resolution Procedure NPRR110  Note: PRS recommended these NPRRs for approval on April 18

4. ROS Meeting – 05/15/084Texas Nodal Program - TPTF Update Last month at TPTF / April 2008 Major Accomplishments / April 21 – 22, 2008:April 21 – 22, 2008 Early Delivery Systems (EDS) Project:  On April 21, TPTF endorsed NPRR119, Resource Limit CalculatorNPRR119  NPRR119 revises the Low-Dispatch Limit (LDL) equation in Nodal Protocols Section 6.5.7.2 (8) to ensure that the LDL and High- Dispatch Limit (HDL) passed to Security Constrained Economic Dispatch (SCED) do not exceed the High-Sustained Limit (HSL) under any circumstance  On April 21, TPTF approved the EDS 3 Load Frequency Control (LFC) Testing Market Participant Handbook v1.02  v1.02 of the handbook revises the completion criteria for the Area Control Error (ACE) verification to account for differences in scan rates between the zonal and nodal software. The handbook criteria is synchronized with metric EMO5, Verify ACE Performance.  On April 21, TPTF endorsed the results of the seven-day ACE comparison (see Key Documents for the meeting) per metric EMO5

5. ROS Meeting – 05/15/085Texas Nodal Program - TPTF Update Last month at TPTF / April 2008 Major Accomplishments / April 21 – 22, 2008 (cont’d):April 21 – 22, 2008 Program Management Office (PMO):  On April 21, TPTF endorsed:  revisions to metric E8, ERCOT Staffed for Texas Nodal Operations  revisions to metric EMO5, Verify ACE Performance  the new metric MP20, Market Participant Ability to Submit Outage - Connectivity Test (MP20 measures the ability of Market Participants to submit Outages to the Nodal Outage Scheduler during EDS 4 Release 9.2 testing) Note: Metrics E8, EMO5, and MP20 were approved by TAC on May 8 Visit Nodal Metrics on the Nodal Transition Readiness CenterNodal Metrics

6. ROS Meeting – 05/15/086Texas Nodal Program - TPTF Update Last month at TPTF / April 2008 Major Accomplishments / April 21 – 22, 2008 (cont’d):April 21 – 22, 2008 Other—Endorsement/Approval of:  On April 22, TPTF approved the final set of changes recommended by the Day-Ahead Market (DAM) Subgroup to incorporate the Market Management System (MMS) functionality for co-optimizing self- committed units in DAM. The changes affect the MMS DAM and Supplemental Ancillary Service Market (SASM) Requirements (B2) v2.0. TPTF assigned the functionality a preliminary status of “needed for go-live” and requested that ERCOT would conduct a cost/schedule impact analysis for incorporating the changes. The TPTF requested that the MMS team would report its results back to TPTF no later than May 15, 2008. The details of the report are scheduled for discussion during the upcoming May 22-23 TPTF meeting.May 22-23  On April 22, TPTF approved revisions to Section 2 of the Commercial Systems (COMS) White Paper - Details on the Settlement of Combined Cycle Plants.

7. ROS Meeting – 05/15/087Texas Nodal Program - TPTF Update This month at TPTF / May 2008 During May 2008:  TPTF held a WebEx to discuss the Single-Entry Model Milestone on May 1May 1  TPTF met on May 5 – 7May 5 – 7  TPTF will meet again on May 22 – 23May 22 – 23

8. ROS Meeting – 05/15/088Texas Nodal Program - TPTF Update This month at TPTF / May 2008 WebEx - Single-Entry Model Milestone/ May 1, 2008:May 1, 2008 On May 1, ERCOT and Market Participants held a WebEx meeting to discuss the Single-Entry Model (SEM) Milestone, including:  The go-live date for the Single-Entry Model (SEM), which was recently moved from June 2 to July 14 owing to defects for Network Model Management System (NMMS) and delays for the Energy Management System (EMS) Common Information Model (CIM) Importer  The criteria for achieving the SEM Milestone  Market Participant Concerns

9. ROS Meeting – 05/15/089Texas Nodal Program - TPTF Update This month at TPTF / May 2008 WebEx – SEM Milestone/ May 1, 2008 (cont’d):May 1, 2008 On May 1, ERCOT and Market Participants discussed the following criteria for achieving the SEM Milestone:  Establish a complete and consistent Nodal Model by:  Confirming the ability to import NMMS ERCOT CIM  Successfully executing EMS applications  Confirming comparison of the Nodal Network Operations Model (NOM) to the Zonal NOM  Deploy the NMMS tool to production  Complete the NMMS Market Trials/ confirm ability of Transmission Service Providers (TSPs) to submit NOM Change Requests (NOMCRs)  Resolve any Severity Level 1 and 2 defects affecting NMMS Note: During the WebEx, it was noted that the SEM Milestone criteria do not include error-free CIM exchanges or requests for the Planning Model because these aspects are to be developed iteratively following go-live for the SEM.

10. ROS Meeting – 05/15/0810Texas Nodal Program - TPTF Update This month at TPTF / May 2008 WebEx – SEM Milestone/ May 1, 2008 (cont’d):May 1, 2008 On May 1, ERCOT and Market Participants discussed the following concerns:  Market Participants will be non-compliant with applicable Nodal Protocols when Section 3 becomes effective in July 2008 per the Nodal Protocol Transition PlanNodal Protocol Transition Plan  TSPs expect to need more time to verify/synchronize the NOM with their systems than what will be provided between SEM go-live and the 168-Hour Test  Market Participants are concerned that the delayed SEM Milestone could affect the Texas Nodal Market Implementation Date Note: On May 8, TAC requested that a meeting be scheduled to address the above concerns and to establish a common understanding between ERCOT and Market Participants regarding what entails NOM validation.May 8 These issues will be discussed at the NDSWG on May 20.May 20

11. ROS Meeting – 05/15/0811Texas Nodal Program - TPTF Update This month at TPTF / May 2008 Major Accomplishments / May 5 – 7, 2008:May 5 – 7, 2008  Endorsement of NPRRs:  On May 5, TPTF endorsed:  NPRR 117, Resource Registration Clarification NPRR 117  NPRR123, Inadvertent Energy Account Revision NPRR123  On May 5, TPTF endorsed:  NPRR107, Nodal Emergency Interruptible Load Service (EILS) NPRR107  NPRR111, Timelines for Response by ERCOT to Transmission Service Provider (TSP) Requests NPRR111  NPRR118, Synchronization of Zonal Protocols for Section 14 NPRR118  On May 7, TPTF endorsed:  NPRR120, Corrections and Clarifications for Real-Time Settlements NPRR120  NPRR122, Simplify Ancillary Services Settlement Formulas NPRR122  Draft NPRR, CRR Settlements Revenue Equalization (this draft NPRR has been posted as NPRR130)NPRR130

12. ROS Meeting – 05/15/0812Texas Nodal Program - TPTF Update This month at TPTF / May 2008 Upcoming Agenda Items / May 22 – 23, 2008:May 22 – 23, 2008 Nodal Program Updates:  Nodal Program Update/ Nodal Timeline Update  PMO Readiness Update  Quality Center Update Nodal Project Updates:  Infrastructure (INF) Update  Discuss Critical Cyber Assets (CCAs) and Critical Infrastructure Protection (CIP) training  Review disposition of comments for the INF Market Participant Identity Management (MPIM) Requirements v3.2

13. ROS Meeting – 05/15/0813Texas Nodal Program - TPTF Update This month at TPTF / May 2008 Upcoming Agenda Items / May 22 – 23, 2008 (cont’d):May 22 – 23, 2008 Nodal Project Updates (cont’d):  EDS Update:  Review disposition of comments for the Texas Nodal Market Go- Live Procedure v0.06  Review disposition of comments for the EDS Emergency Operations Test Plan v0.01  MMS Update  Discuss vendor impact studies to incorporate changes for:  co-optimization of self-committed Resources in DAM  NPRR102, Implementation of PUC Subst. R. 25.505(f), Publication of Resource and Load Information NPRR102

14. ROS Meeting – 05/15/0814Texas Nodal Program - TPTF Update This month at TPTF / May 2008 Upcoming Agenda Items / May 22 – 23, 2008 (cont’d):May 22 – 23, 2008 Other Agenda Items:  Market Rules Update  Review comments for recently "nodalized" protocol sections:  NPRR114, Section 11, Data Acquisition and Aggregation NPRR114  NPRR126, Section 19, Texas Standard Electronic Transaction NPRR126  NPRR129, Section 15, Customer Registration NPRR129  Review disposition of comments for NOGRRs  NOGRR018- Synchronization of OGRR204, Hotline Technology Update * NOGRR018  NOGRR019- Synchronization of OGRR206, Black Start Satellite Phones * NOGRR019 * Note: During the May 5-7 meeting, TPTF requested the opportunity to comment on “nodalizations” of the Operating Guides.

15. ROS Meeting – 05/15/0815Texas Nodal Program - TPTF Update This month at TPTF / May 2008 Upcoming Agenda Items / May 22 – 23, 2008 (cont’d):May 22 – 23, 2008 Other Agenda Items:  Review Draft NPRR Language for Outage file formats for the  Network Operations Model, Section 4.2.3 (a)  Annual Planning Model, Section 3.10.2 (3)  CRR Network Model, Section 3.10.3 (5)  Review NPRR124, Resource Node Updated Definitions, and discuss whether the existing Nodal Protocol definition for Resource Node should be revised to incorporate descriptions of specific Resource Node typesNPRR124  NPRR128, Combined-Cycle Power Blocks with Multiple Voltage Interconnections NPRR128  Review draft NPRR to clean up Section 7 for Flowgate Settlements  This draft NPRR adds clarifications to the flowgate definition and related settlement formulae.

16. ROS Meeting – 05/15/0816Texas Nodal Program - TPTF Update Future TPTF Meetings / June 2008 Future TPTF Meetings / June 2008:  June 9 – 10, 2008  June 23 – 25, 2008

17. ROS Meeting – 05/15/0817Texas Nodal Program - TPTF Update Questions? Please direct questions or comments to: Stacy Bridges sbridges@ercot.com 512.248.6709