RPCG – CCTA Process Vijay Satyal & Colby Johnson Reliability Planning & System Adequacy April 28, 2015 W ESTERN E LECTRICITY C OORDINATING C OUNCIL

RPCG Update from Chair/Vice-Chair Purpose – Soliciting input on - potential transmission projects with probability of being in-service in the next 10 years – Assist with best-estimates on transmission topology – Stakeholder driven to reflect diversity of views 2 W ESTERN E LECTRICITY C OORDINATING C OUNCIL

CCTA Process Critical for WECC interconnection-wide planning Criteria-driven process (quantitative & subjective) Stakeholder input before submittal to TAS Valuable for future planning for Regional Planning Groups 3 W ESTERN E LECTRICITY C OORDINATING C OUNCIL

Why is this valuable? Inaccurate data/assumptions on transmission projects Inconsistency in modeling assumptions Potential under/over-estimation of transmission utilization/congestion levels 4 W ESTERN E LECTRICITY C OORDINATING C OUNCIL

2024 CCTA Process February 2013: 2024 CCTA process initiated May 2013: Project sponsors requested to update information in the WECC Project Information Portal (PIP) March – September 2013: Develop and revise 2024 CCTA 5 W ESTERN E LECTRICITY C OORDINATING C OUNCIL

2024 CCTA Process Results 6 W ESTERN E LECTRICITY C OORDINATING C OUNCIL

2026 Common Case Development Timeline (Tentative) 7 W ESTERN E LECTRICITY C OORDINATING C OUNCIL 2026 Common Case Tentative: 2025 HS Powerflow 2026 CCTA 2026 Load Forecast March April May June July August HS Powerflow2026 CCTA2026 Load Forecast

8 W ESTERN E LECTRICITY C OORDINATING C OUNCIL Today FebMarAprMayJunJulAugSepOctNovDec 2015 Project Kickoff In-person meeting CCTA Process Kickoff Update Project Portal Develop and Revise CCTA Assumptions Aug 15Sep 15 Final CCTA review 2026 Common Case Kickoff

2024 CCTA Selection Process 9 W ESTERN E LECTRICITY C OORDINATING C OUNCIL Project Screening and Selection Process 2024 Common Case Transmission Assumptions Regional significance Project Development Indicators RPCG 10-year plans WECC Project Information Portal (PIP) 2024 CCTA Information Gathering Process

2024 CCTA Process and Selection 10 W ESTERN E LECTRICITY C OORDINATING C OUNCIL RPCG

2024 CCTA Criteria Criteria 1: Regional Significance Based on Voltage: greater than or equal to 500kV or 345kV; greater than or equal to 200kV if backbone element (e.g., eastern edge of Western Interconnection) Criteria 2: Construction Status Is the project currently under construction? Criteria 3: Financial Indicators Financial questions added to project survey to indicate if the project has financial commitment Criteria 4: Implementation Status Indicators Environmental Impact Status (EIS – if required) questions added to survey Criteria 5: Project Dependency Is this project dependent upon another transmission project to be completed and used for its intended purpose? If so, did the dependent project pass the CCTA criteria? 11 W ESTERN E LECTRICITY C OORDINATING C OUNCIL

Questions/Discussion Continue with same process as before? Add/Update? – Other metrics for review Better way to do things? – Flexibility in process improvement – Timeliness – Replicability 12 W ESTERN E LECTRICITY C OORDINATING C OUNCIL

13 Vijay A Satyal – Sr. Energy Policy Analyst, Reliability Planning Colby Johnson – Associate Engineer, System Adequacy Thank you & Questions?