1. Transmission Outage Process April 2003

2. Purpose In compliance with the Protocols and the Electric Reliability Council of Texas (ERCOT) Operating Guides, ERCOT implements the following Transmission Outage Approval Process.

3. Goals 1.Reliable operation 2.Maximize availability of the transmission system 3.Provide the electric market in ERCOT with information 4.Support good utility practice

4. Types Of Outages Planned New/Relocated Tentative Forced

5. Tentative Outage Request Type The new “Tentative Outage” request type will be received with an inactive format “information only”. Preferred firm dates must be entered and the outage must be changed to a “Planned” request type before it enters the outage approval process. Tentative Outages will provide the flexibility to enter long range outages without firm dates. This will better provide information for the Rolling Twelve Month Outage Plan and allow better overall coordination between ERCOT and TSP’s.

6. Forced Outage: (Immediate) An Outage initiated by protective relay, or manually in response to an observation by field personnel or the TSP System Operator that equipment poses a threat to personnel or equipment. The TSP may remove such equipment from service immediately and notify ERCOT of its action.

7. Level 1 Outage: Equipment that must be removed from service within 24 hours to prevent a potential Forced Outage, but may be removed immediately, if necessary.

8. ERCOT actions to a Forced Outage Transmission and Security Operator will: run a Security Analysis study withdraw previous approvals of other outages or implement constraint management guidelines if needed

9. Transmission Outages submitted for approval appear immediately on the ERCOT Public website in the Proposed Transmission Outages folder. After ERCOT Approval, the outage moves to the Approved Transmission Outages folder. Tentative Transmission outages are listed in Proposed Transmission Outages folder. Forced Transmission outages are listed in Approved Transmission Outages folder. Posting Of Market Data To ERCOT Website

10. Approval Timeline 3 1 45 40 35 30 25 20 15 10 9 8 7 6 5 4 2 4 30 Planned Start Day of Outage

11. Peak demand conditions Present generation patterns Planned generation Outages Other Planned transmission Outages Forced Outages ERCOT Considerations

12. ERCOT Concerns Transmission Loading under contingency conditions Voltage under contingency conditions Good Utility Practice

13. Alternatives to Rejecting An Outage Remedial Action Plans Adjust Timing of Outage Temperature Adjustments to Ratings Generation Requirements Generation Limitations Special Protection Schemes

14. Reject Approve Outage Approval Flowchart

15. Rejection Notice Identify specific reliability concerns Suggest possible remedies

16. Withdrawal of Approval Reliability Standards Cannot be Met Information Supplied & Documented

17. Outage Coordinator Timeline

18. 06:00 Morning Outage Transmission Security Meeting Discuss Monday & Tuesday outages Analysis for Wednesday Outages Coordination details and operation requirements finalized Engineering Group consulted for any concerns with limits Outages approved/rejected. Outage notes Created, printed and distributed 15:00 Evening Outage Transmission Security Meeting Discuss Tuesday & Wednesday outages. Outage Coordinator Timeline

19. Planning 12 Month Planned Outage Program –Required Seasonal Updates VIA Outage Scheduler Transmission Coordinator Meetings –Minimum 2 per year( Spring & Fall Seasons) Other meetings as required –

20. 2002 Active Outages 22,569 submitted for Approval

21. 2002 Transmission Outages

22. 2002 Transmission Outage Requests

23. 2002 Analysis

24. Plan for 2003 Study Transmission Outages that are over 5 continuous Days in length in greater detail. Coordinate RMR and Transmission Outages Improve 12 Month Outage Plans Upgrade Transmission outage website to help market identify outages that have impact.

25. Actual Start And Actual End Times Entries Circuit Breaker Line Identification Electronic Forced/Level I Form Outage Scheduler Enhancements

26. Questions ???