GREDP Monitoring QSE Manager’s Working Group December 15, 2010

2 QSE Managers Working Group15 December 2010 Agenda GREDP Summary for NON-IRRs GREDP Summary for IRRs Communication to MPs

3 QSE Managers Working Group15 December 2010 GREDP Summary for NON-IRRs (12/1 – 12/13) GREDP Calculation GREDP (%) = ABS[((ATG – AEPFR)/(ABP + ARI)) – 1.0]*100 GREDP(MW) = ABS(ATG – AEPFR – ABP - ARI) Stipulations/Exclusions Must be online and released to SCED Net MW > LSL Intervals must have GREDP % < 8% or GREDP MW < 8 MW Intervals passed/Intervals scored > 85% Excludes forced outages, emergency BPs, or frequency deviations Score Summary 344 On-line and released to SCED at one point, 253 received a GREDP score 23 Resources < 85% Monthly GREDP Compliance 21 Resources < 3% of the month released to SCED 2 Resources ~ 65% of the month released to SCED 1 Data Issue 1 Resource consistently not following BPs

4 QSE Managers Working Group15 December 2010 GREDP Summary for IRRs (12/1 – 12/13) GREDP Calculation GREDP (%) = ABS[((ATG – AEPFR)/(ABP + ARI)) – 1.0]*100 GREDP MW = ATG – AEPFR – ABP – ARI Stipulations/Exclusions Must be online and released to SCED Net MW > LSL Resource must be curtailed (HSL-BP >= 2) Interval must have GREDP % < 10 or GREDP MW must be positive Intervals passed/Intervals scored > 95% Excludes forced outages, emergency BPs, or frequency deviations Score Summary 85 WGRs total, 42 received a GREDP score 29 WGRs < 95% Monthly GREDP Compliance Nearly all WGRs released to SCED ~ 100% 5 WGRs Monthly GREDP Compliance % < 20% 2 WGRs Monthly GREDP Compliance % >= 20% and < 60% 22 WGRs Monthly GREDP Compliance % >= 60%

5 QSE Managers Working Group15 December 2010 Monitoring and Communication Resources not meeting GREDP requirements ERCOT plans to contact QSEs that are responsible for these resources QSEs will be made aware and will have an opportunity to improve their score First GREDP report will be released in the first week of January. Report is available on the MIS Compliance and Disclosure > Compliance Reports – QSE > “Monthly Energy Resource Deployment Report” Protocol View > Section 8 > (4) > “Monthly Energy Resource Deployment Report” Proper venue to discuss appropriateness of the GREDP Metric