Technical Advisory Committee

1. Technical Advisory Committee Presentation to the ERCOT Board of Directors February 20, 2007

2. Today’s TAC Report • Three PRRs. • Changes to BOD approval processes. • Emergency Interruptible Load Service (EILS) update. • Task Force Comings and Goings • 2006 TAC Accomplishments and Goals for 2007.

3. PRR 691 – Nodal Implementation Surcharge Verifiable Costs

4. PRR 691 – Nodal Implementation Surcharge Verifiable Costs No Impact Impact Description Item Reviewed Budget Staffing Computer Systems Impact absorbed with current processes Business Functions Grid Operations Credit Monitoring/ Liability

5. PRR 694 – Modification of Certain Board Approvals

6. PRR 694 – Modification of Certain Board Approvals No Impact Impact Description Item Reviewed Budget Staffing Computer Systems Business Functions Grid Operations Credit Monitoring/ Liability

7. TAC/BOD Process Changes in PRR 694 • No longer approved by the BOD: • Exemptions from compliance with metering protocols. • Changes among load profiling methodologies, models, and implementation timelines. • A PRR passed by TAC will continue to the BOD on the current schedule if: • No project is required; or • An associated project can be accommodated in the current budget cycle.

8. TAC/BOD Process Changes in PRR 694 (con’t) • A PRR passed by TAC will be held before moving to the BOD for approval if: • An associated project cannot be completed within the current budget cycle. • The PRR will be held in the “unfunded project list” until the BOD approves a new budget that accommodates the project or the project priority is changed. • The unfunded project list will be reviewed by TAC each quarter. • All projects on the unfunded project list for 2 years will be re-evaluated by PRS.

9. PRR 695 – Unaccounted for Energy (UFE) Analysis

10. PRR 695 – Unaccounted for Energy (UFE) Analysis No Impact Impact Description Item Reviewed Budget Staffing Computer Systems Business Functions Grid Operations Credit Monitoring/ Liability

11. Recommended TAC Actions • Approval • PRR 691– Nodal Implementation Surcharge Verifiable Costs • PRR 694 – Modification of Certain Board Approvals • PRR 695 – Unaccounted for Energy (UFE) Analysis

12. Emergency Interruptible Load Service (EILS)--Update • In fall of 2006, TAC charged the WMS with developing an EILS. • 1000 MW of interruptible load. • Deployed between EECP steps 3 and 4. • Baseline and performance fully measurable. • WMS has developed four possible PRRs to provide EILS (one developed by ERCOT), which are now pending at PRS.

13. Emergency Interruptible Load Service (EILS)—Update (con’t) • WMS in January failed to pass the following resolution (0-15-2): “At this point in time, WMS is confident an Emergency Interruptible Load Service is a necessary component of ERCOT’s EECP toolbox to avoid firm load shed.” • PRS at its January meeting passed with two opposed the following resolution: “PRS concurs with ERCOT that curtailing voluntary firm load in emergency conditions is preferable to shedding firm load on an involuntary bases. However, PRS is not yet convinced that such a program is appropriate for two reasons: 1. The market has changed since April 17, 2006; 2. Whether it can be implemented for a cost commensurate with the value of lost load (VOLL) associated with rotating outages during emergency conditions.” Therefore, at this time, PRS declines to recommend approval or rejection of any PRRs related to EILS until questions related to the need and efficacy of such a service are more firmly established…

14. Emergency Interruptible Load Service (EILS)—Update (con’t) • PRS questions referred to ROS: • What is the statistical likelihood, given ERCOT Operator flexibility in the EECP process, that EILS will be utilized as envisioned prior to firm Load shedding? • Rate the impact of each of the EILS PRRs on ERCOT’s Loss of Load Probability (LOLP). • Evaluate the EILS PRRs’ procurement methodologies. What is the appropriate amount of EILS to procure, if any? • Evaluate the EILS PRRs’ deployment methodologies. Address any concerns that arise from deployment and recall. • What other alternatives to EILS, such as procuring additional existing Ancillary Services, could be utilized to achieve similar results?

15. Emergency Interruptible Load Service (EILS)—Update (con’t) • PRS questions referred to ERCOT Staff: • What is the statistical likelihood, given ERCOT Operator flexibility in the EECP process, that EILS will be utilized as envisioned prior to firm Load shedding? • Rate the impact of each of the EILS PRRs on ERCOT’s LOLP. • What alternatives to EILS were examined by ERCOT, if any, and why was EILS pursued instead of those other options? • Has the Value of Lost Load (VOLL) been determined for the April 17, 2006 load shedding event? If so, please share the methodology and results of that study. If not, why not?

16. Emergency Interruptible Load Service (EILS)—Update (con’t) • PRS assigned the WMS to define the following: • The benefit of each proposal. • The cost based on the EILS PRRs. • Changes in Market since April 17, 2007.

17. Emergency Interruptible Load Service (EILS)—Update (con’t) • PRS will consider the 4 EILS PRRs at it’s meeting Wednesday after receiving input from ERCOT, ROS, and WMS. • In early February, the PUC issued a proposed rule adopting an EILS. • Based on ERCOT’s proposal. • Costs capped at $17 million for 2007. • Designed to sunset October 1st if certain conditions are met. • Stakeholders are directed to develop a long-term solution.

18. Task Force Comings and Goings • Disbanded: • RMS • Mass Transition Task Force (MTTF) • Terms and Conditions Task Force (TCTF) • COPS • Commercial Protocol Review Working Group (CPRWG) • WMS • Emergency Interruptible Load Task Force (EILTF) • Created: • COPS • Settlements and Data Aggregation Working Group (SDAWG) • WMS • Renewables and Transmission Task Force (RTTF)