1. September 2010 Wholesale Market Subcommittee Report to Technical Advisory Committee

2. 2 TAC Action Items TAC Voting Items on other Parts of the Agenda –NPRR 220 Nodal Requirement of Declaring an EEA for Reserves more than 500 MW WMS considered and voted to endorse NPRR220 as submitted. There were two opposing votes from the Independent Generator and Independent Power Marketer (IPM) Market Segments and two abstentions from the Consumer and Municipal Market Segments. All Market Segments were present for the vote. Recommend TAC Approval

3. 3 TAC Action Items TAC Possible Action Item –DME List for Competitive Constraints Absent DME list being accurate, the Market has no functional fallback position for the Competitive Constraints. IMM has expressed concerns about affiliates on the list but will not be providing edits to the list. http://www.ercot.com/gridinfo/sysplan/index WMS (CMWG) to discuss further in September; TAC Guidance on DME List would be helpful.

4. 4 In Brief Upcoming NPPRs (not on Today’s Agenda) –NPRR256, Synchronize Nodal Protocols with PRR787, Add Non-Compliance Language to QSE Performance Standards (formerly “Add Violation Language to QSE Performance Standards”) WMS (QMWG) and NATF are continuing to discuss this NPRR and will have a recommendation in the future. –NPRR: Wind-powered Generation Resource (WGR) / Intermittent Renewable Resource (IRR) Base Point Deviation WMS directed QMWG to draft an NPPR for WMS submission in September to grey box language use correct HSL, to correct the negative price issue, and to provide options to deal with other issues that cannot be correct with protocol changes.

5. 5 Working Groups CMWG –General Update – DME List for Competitive Constraints WCATF –Disbanded DSWG –No Report MCWG –Nodal Market Trial Credit Monitoring Management (CMM) Performance Discussion –Third Party Credit Administration – Other Markets –First Priority Security Interest Agreement for Congestion Revenue Rights (CRRs) –Report on Joint Meeting with CWG Nodal Credit Readiness CRR Auction Credit Requirements PSWG –No Report

6. 6 Working Groups QMWG –NPRR256 –2011 Ancillary Service Methodology WMS Recommendations –Generation Resource Energy Deployment Performance (GREDP) Calculations and other Nodal Reliability Performance Metrics –Draft NPRR: Base Point Deviation –WGR Real-Time Production Potential (RTPP) Data and Meteorological (MET) Data Update VCWG –Minor changes to the Nodal Verifiable Cost Manual MWG – No report QSTF – No report GATF – No report WCATF – No report

7. 7 Upcoming/Continuing Discussion Points Nodal Price Convergence with Zonal Nodal Test Outcomes… review and recommend

8. 8 WMS GOALSItemsWMS input/direction needed byWMS input/direction needed by Nodal Market TransitionNodal Market TransitionOn-going Market Participant Readiness Market Participant Readiness TCR to CRR Transition TCR to CRR Transition Nodal Protocol Tracebility Nodal Protocol Tracebility Nodal Parking Deck Nodal Parking Deck Nodal Test Evaluation Nodal Test Evaluation Nodal Verifiable Cost MethodologyNodal Verifiable Cost MethodologyOn-going (VCWG)On-going (VCWG) Consideration of necessary Zonal Market changesConsideration of necessary Zonal Market changesBefore Q2Before Q2 Review of Generation Adequacy in ERCOTReview of Generation Adequacy in ERCOTQ1 (GATF)Q1 (GATF) Market Issues Related to:Market Issues Related to: Credit issuesCredit issuesOn-going (MCWG)On-going (MCWG) EILSOn-going (DSWG)On-going (DSWG) Reliability & A/S Dispatch Impacts on Energy MarketsReliability & A/S Dispatch Impacts on Energy MarketsOn-going Market Event EvaluationMarket Event EvaluationOn-going Adv. meters & other demand response in A/S and Energy MarketsAdv. meters & other demand response in A/S and Energy MarketsOn-going (DSWG)On-going (DSWG) Wind & related renewable technology integrationWind & related renewable technology integrationOn-going (various WG)On-going (various WG) Criteria in Nodal for supplying A/S, Energy and Capacity MarketsCriteria in Nodal for supplying A/S, Energy and Capacity MarketsOn-going (WMS)On-going (WMS) Integration of Quick Start Resources into NodalIntegration of Quick Start Resources into NodalQSTF Power Storage DevicesOn-going (TBD) LaaR Responsive Reserve Performance Penalty On-going (DSWG)On-going (DSWG)

9. 9 QUESTIONS