1. © ERCOT 2004 1 2003 and 2004 Fleet Deployment and Settlements WMS Meeting August 19, 2004 Ino Gonzalez ERCOT Settlements igonzalez@ercot.com www.ercot.com

2. © ERCOT 2004 2 Fleet Cost Summary 2

3. © ERCOT 2004 3 Fleet MWh Summary 3

4. © ERCOT 2004 4 Fleet MWh Summary 4

5. © ERCOT 2004 5 Location of Deployment 5

6. © ERCOT 2004 6 Percent Fleet Deployment by Location 6

7. © ERCOT 2004 7 2004 Plant Deployment and Settlements 7

8. © ERCOT 2004 8 Plant Cost Summary 8

9. © ERCOT 2004 9 2004 Plant Summary 9

10. © ERCOT 2004 10 Fleet Deployment Settlement Process 10

11. © ERCOT 2004 11 What are Fleet Instructions? QSE 1 --- decrease generation in the North Zone by 100 MW for interval ending 9:15. QSE 2 --- increase generation in the Houston Zone by 100 MW for interval ending 9:15. Increase/Decrease Generation ERCOT-Wide by 100 MW Have output of plant 1 at or below 450 MW. [This is not a fleet instruction.] 11

12. © ERCOT 2004 12 High Level ---What is being done by the ERCOT Settlements Group ? Create ZIDUPADJ’S and ZIDDNADJ’s to reflect the Fleet Instruction to ensure URC is calculated correctly. [Done before the Initial is run.] Determine if the QSE followed the “Fleet Instruction”. Identify which type of units were moved in order to follow the Fleet Instruction. (assume economic dispatch.) Create and import unit fuel type payments* (premium) to the QSE for following “fleet instruction”. * QSEs received Balancing Energy Payments via the Resource Imbalance 12

13. © ERCOT 2004 13 Additional Fleet Settlement Information For more detail information on the Fleet Settlement process, please review the “ERCOT Fleet Settlement Procedures” located at: http://www.ercot.com/Participants/MarketBulletins.htm 13

14. © ERCOT 2004 14 QUESTIONS, DISCUSSION