1. Protocol Revision Subcommittee Presentation to the ERCOT Technical Advisory Committee May 4, 2007

2. PRS Summary 6 PRRs for Approval 6 PRRs for Approval Non-System Changes – IAs only Non-System Changes – IAs only 2 NPRRs for Approval 2 NPRRs for Approval 1 Notice of Rejection; 1 Withdrawal 1 Notice of Rejection; 1 Withdrawal Updates Updates Nodal NPRR Implementation Process Nodal NPRR Implementation Process PRR Appeals Process PRR Appeals Process “Pens Down” on Zonal Wholesale System Changes “Pens Down” on Zonal Wholesale System Changes

3. PRR 701 – Enabling of Stranded Capacity During Alerts -- URGENT Purpose (PSEG, IGEN) Allows QSEs to represent previously stranded capacity as available and capable of being included in their capability during an Alert Benefit May provide ERCOT incremental on-line capacity during alerts Market Impact N/A System Change NoN/A AssumptionsN/A PRS Vote PRS recommended approval with 1 opposed and 3 abstentions; all market segments were present Effective Date June 1, 2007

4. PRR 701 – Enabling of Stranded Capacity During Alerts -- URGENT Item Reviewed Description NoImpact Credit Monitoring/ Liability Budget Staffing Computer Systems Business Functions Grid Operations Impact

5. PRR 709 – Scarcity Pricing Mechanism Purpose(ERCOT) Incorporates scarcity pricing mechanism including offer caps. ERCOT Staff is currently performing these calculations. Benefit Conforms to PUC Subst. R. 25.505(g) Market Impact N/A System Change NoN/A AssumptionsN/A PRS Vote PRS recommended approval unanimously; all market segments were present Effective Date Effective July 1, 2007

6. PRR 709 – Scarcity Pricing Mechanism Item Reviewed Description NoImpact Credit Monitoring/ Liability Budget Staffing Computer Systems Business Functions Grid Operations Impact

7. PRR 710 – Validation Tests Update Purpose (Reliant Energy, IPM) Removes requirement to post exception reports stemming from the Load Profile Type and Weather Zone validation tests to the MIS Benefit Corrects current protocol language Market Impact N/A System Change NoN/A AssumptionsN/A PRS Vote PRS unanimously recommended approval; all market segments were present Effective Date July 1, 2007

8. PRR 710 – Validation Tests Update Item Reviewed Description NoImpact Credit Monitoring/ Liability Budget Staffing Computer Systems Business Functions Grid Operations Impact

9. PRR 711 – Update of ERCOT Protocols to Comply With NERC Name Change Purpose(ERCOT) Updates protocols references to NERC; reflects name change. Benefit Conforms protocols to current NERC name. Market Impact N/A System Change NoN/A AssumptionsN/A PRS Vote PRS unanimously recommended approval; all market segments were present Effective Date July 1, 2007

10. PRR 711 – Update of ERCOT Protocols to Comply With NERC Name Change Item Reviewed Description NoImpact Credit Monitoring/ Liability Budget Staffing Computer Systems Business Functions Grid Operations Impact

11. PRR 712 – Local Congestion Replacement Reserve Payment Methodology Purpose (ERCOT on behalf of WMS) Modifies RPRS local congestion payment method to be identical to OOMC; inserts a “Max” function in the start-up and operating calculations. Benefit Consistency in settlement between the two similar services. Market Impact N/A System Change NoN/A AssumptionsN/A PRS Vote PRS recommended approval with 1 opposing and 1 abstention; all market segments were present Effective Date July 1, 2007/upon system implementation

12. PRR 712 – Local Congestion Replacement Reserve Payment Methodology Item Reviewed Description NoImpact Credit Monitoring/ Liability Budget Staffing Computer Systems Business Functions Grid Operations Impact Managed w/in current budget Minor Lodestar modification under current budget

13. PRR 716 – Self-Provision of Emergency Interruptible Load Service -- URGENT Purpose (CPS Energy, Muni) Amends EILS protocol to allow for self-provision by all QSEs; addresses PUC Subst. R. 25.507(i); update ERCOT forms following initial RFP Benefit Allows QSEs to self-provide EILS Market Impact May increase LRS cost to QSEs not self-providing System Change NoN/A AssumptionsN/A PRS Vote PRS recommended approval by segment vote of 5.667 to 0.333 with 5 abstentions; all market segments were present Effective Date June 1, 2007

14. PRR 716 – Self-Provision of Emergency Interruptible Load Service -- URGENT Item Reviewed Description NoImpact Credit Monitoring/ Liability Budget Staffing Computer Systems Business Functions Grid Operations Impact Managed w/in current budget May require minor system modifications

15. PRR Summary PRRs Recommended for Approval PRRs Recommended for Approval PRR 701 – Enabling of Stranded Capacity During Alerts -- URGENT PRR 701 – Enabling of Stranded Capacity During Alerts -- URGENT PRR 709 – Scarcity Pricing Mechanism PRR 709 – Scarcity Pricing Mechanism PRR 710 – Validation Tests Update PRR 710 – Validation Tests Update PRR 711 – Update of ERCOT Protocols to Comply with NERC Name Change PRR 711 – Update of ERCOT Protocols to Comply with NERC Name Change PRR 712 – Local Congestion Replacement Reserve Payment Methodology PRR 712 – Local Congestion Replacement Reserve Payment Methodology PRR 716 – Self-Provision of Emergency Interruptible Load Service (EILS) -- URGENT PRR 716 – Self-Provision of Emergency Interruptible Load Service (EILS) -- URGENT

16. NPRR 046 – Real-Time ICCP Communications Only Purpose(ERCOT) Requires all real-time communications will use ICCP. Benefit Ensures that required data volume can be supported and meet data quality requirements. Market Impact N/A System Change NoN/A AssumptionsN/A PRS Vote PRS unanimously recommended approval; all market segments were present Effective Date N/A

17. NPRR 046 – Real-Time ICCP Communications Only Item Reviewed Description NoImpact Credit Monitoring/ Liability Budget Staffing Computer Systems Business Functions Grid Operations Impact Managed w/in current budget and schedule

18. NPRR 054 – Update of Nodal Protocols to Comply with NERC Name Change Purpose(ERCOT) Updates protocols references to NERC; reflects name change; companion NPRR to PRR 711. Benefit Conforms protocols to current NERC name. Market Impact N/A System Change NoN/A AssumptionsN/A PRS Vote PRS unanimously recommended approval; all market segments were present Effective Date N/A

19. NPRR 054 – Update of Nodal Protocols to Comply with NERC Name Change Item Reviewed Description NoImpact Credit Monitoring/ Liability Budget Staffing Computer Systems Business Functions Grid Operations Impact Managed w/in current budget and schedule

20. NPRR Summary NPRRs Recommended for Approval NPRRs Recommended for Approval NPRR 046 – Real-time ICCP Communications Only NPRR 046 – Real-time ICCP Communications Only NPRR 054 – Update of Nodal Protocols to Comply with NERC Name Change NPRR 054 – Update of Nodal Protocols to Comply with NERC Name Change

21. Other PRR Status NPRR056 – Modify Competitive Load Zones NPRR056 – Modify Competitive Load Zones Rejected by segment vote of 4.0 to 1.0 with 5 abstentions; Coop Segment was not present Rejected by segment vote of 4.0 to 1.0 with 5 abstentions; Coop Segment was not present PRR 715 – Simplifying the Dispute Process PRR 715 – Simplifying the Dispute Process Withdrawn by the submitter Withdrawn by the submitter

22. PRS Activity Summary Established task forces to address the following topics: Established task forces to address the following topics: PRR Appeals Process (TAC assignment) PRR Appeals Process (TAC assignment) PRR 719 Review PRR 719 Review

23. PRS Activity Summary “Pens Down” on Zonal Wholesale System Changes “Pens Down” on Zonal Wholesale System Changes Recognized that the number of PRRs requiring zonal wholesale system changes has slowed Recognized that the number of PRRs requiring zonal wholesale system changes has slowed Deferred discussion until close of legislative session Deferred discussion until close of legislative session

24. PRS Activity Summary Nodal NPRR Implementation Process Nodal NPRR Implementation Process PRS determined existing protocols allow it to defer action on NPRRs not determined to be needed for “go live” PRS determined existing protocols allow it to defer action on NPRRs not determined to be needed for “go live” ERCOT PMO and TPTF process will determine NPRRs needed for “go live” and determination will be reviewed by PRS ERCOT PMO and TPTF process will determine NPRRs needed for “go live” and determination will be reviewed by PRS PRS needs to develop a process for consideration of deferred NPRRs when “go live” + 1 version is structured PRS needs to develop a process for consideration of deferred NPRRs when “go live” + 1 version is structured