Brett Wangen Director of Engineering, Peak Reliability ECC Update 3/22/2017 WECC MIC/OC Joint Meeting Brett Wangen Director of Engineering, Peak Reliability

Current ECC Project Status Real-time situational awareness phase is available for Peak, TOP and BA operators Lessons learned to be addressed in future releases Improve data organization, clear solutions (not just information) for operators Auto define elements based on real-time assessments Benefit of RT situational awareness – provide method for monitoring unique outage constraints, identifying/validating operating plans.

Qualified Path Management Progress ECC supporting Unscheduled Flow Mitigation Plan functionality for Qualified Paths ECC accuracy benefits over webSAS Zonal Source to Sink Colors represent the “zones”

webSAS/ECC Parallel Operations March 1 – June 1 Peak working with BAs to implement detailed mapping between scheduling and operations worlds webSAS users getting access to the ECC ~90% of BAs have access to ECC Peak producing comparison reports for review and discussion (ECC vs. webSAS) Transition plan includes review/acceptance of parallel ops results by UFAS.

Initial Findings of Parallel Operations Tag Name TDF(%) ECC PACE_TAG1_NEVP 10.4 WACM_TAG2_PNM 14.3 PACE_TAG3_LDWP 10.6 WACM_TAG4_WALC 11.5 WACM_TAG5_PSCO 44.7 WACM_TAG6_PSCO WACM_TAG7_PSCO WACM_TAG8_WALC WACM_TAG9_SRP 12 Source to Sink TDFs from ECC ECC/webSAS Differences Source and sink zones same in webSAS (0%) 13 Exempt from curtailment due to crossing phase shifter 18 Source and sink BAs same in ECC (0%) 46 Scheduled MW is 0 21 Zones in webSAS show less than 10% TDF 56 DC Line Mapping Mismatch between ECC and webSAS Total tags in the report 182 Summary of differences found between webSAS and ECC curtailments

Next Steps – Future Hour Initial use case Qualified Paths – what is going to happen next hour? Objective – reduce need for step 3 & 4 actions by having awareness of next hour flows Functionality not limited to Qualified Paths Today, Qualified Path Operators can’t accurately predict if next hour needs relief provided Future hour functionality in the ECC will use real-time snapshots and apply load forecast, scheduled outages, and generator output

= Calculating Value ECCRT + ECCQP + ECCFH – TOP-007-WECC-1 There is a clear cost (reliability and dollars) to adjusting phase shifters and making curtailments based on Qualified Path SOLs Transition to the ECC paradigm will reduce those costs because of Real-time data and assessments driving actions No proxy Path SOLs ECC accuracy and capabilities ECCRT + ECCQP + ECCFH – TOP-007-WECC-1 = INCREASED RELIABILITY AND EFFICIENCY

An Ongoing Paradigm Change “A” is the current state “B” is move of webSAS to ECC “C” implements ECC future hour “D” defines the expanded use of ECC State A TOP-007-WECC-1 webSAS State B No TOP-007-WECC-1 ECC supporting QPs/WIUFMP State D No TOP-007-WECC-1 ECC supporting QPs/WIUFMP Future Hour Info ECC expanded use beyond QPs State C No TOP-007-WECC-1 ECC supporting QPs/WIUFMP Future Hour Info Acknowledge that class 1 and 2 have concerns over policy

TOT 3 Example Based on Nov 2016 Path 36 – TOT 3 Seven lines at 345, 230, and 115kV Thermally limited Limit dynamic based on local generation levels and DC flow and direction Limiting contingencies dependent on generation and DC; generally loss of line or generation results in facility rating exceedances November 2016, TOT 3 WIUFMP actions triggered 20 hours of Step 3 phase shifter operations 14 hours of Step 4 curtailments involving Path 36 Represents both reliability risk and decrease in efficiency

Applying Path 36, November 2016 to Paradigm Change State D No TOP-007-WECC-1 ECC supporting QPs/WIUFMP Future Hour Info ECC expanded use beyond QPs State C No TOP-007-WECC-1 ECC supporting QPs/WIUFMP Future Hour Info State B No TOP-007-WECC-1 ECC supporting QPs/WIUFMP State A TOP-007-WECC-1 webSAS Reliability benefit low low/medium medium high Efficiency benefit Step 3 COPS hours 20 hours ~8 hours N/A Step 4 Curtailments 14 hours ~6 hours Target Date Current June 1, 2017 Q4 2017/ Q1 2018 Q4 2018 State C based on 60% number we have been discussing

ECC Task Force Enable the development of ECC by providing technical, regulatory and policy related input to Peak Upcoming meetings April 3 and 4, CAISO May 4 (webinar) June 13 and 14, Portland (tentative)