TAS & TEPPC Update - 2026 CCTA Assumptions Vijay Satyal - RPCG Liaison, Sr. Policy Analyst & Colby Johnson - Associate Engineer, SAP Western Electricity Coordinating Council

Inputs to the WECC Common Case Resources (DWG/SWG) Process: Transmission Assumptions (RPCG) Loads (DWG) 2026 Common Case

Western Electricity Coordinating Council CCTA process Transmission topology  C Case 2026 Regional Planning Groups  Key entities Mindful of RPGs’ complying with FERC Order 1000 and their criteria Not influenced by FERC Order 1000 criteria Cost-allocation is not the focus for selection RPCG – Ideal forum for such feedback Western Electricity Coordinating Council

Project Information Portal (PIP) 1 3 We have began an outreach/sent a letter to ask for project updates from present project contacts/sponsors 2 Western Electricity Coordinating Council

Edit existing projects through interactive map *Paths shown are approximations and are provided to us in the form of Keyhole Markup Language (KML) by project sponsors/contacts Add new/edit projects through “list view”

CCTA Selection Process Review 2026 CCTA Inclusions All Prior CCTA Projects 2026 CCTA Criteria Under Constr. Not Under Constr. Newly-Submitted CCTA Projects 2026 CCTA Exclusions Western Electricity Coordinating Council

CCTA Not CCTA Criteria 1 No Yes Criteria 2 Criteria 3 Yes No No Yes Regional Significance No Project A Project … Project Z Yes Criteria 2 Under Construction Criteria 3 Financial Indicators Yes No No Yes Criteria 4 Implement. Indicators Yes No Passed RPCG Screen Criteria 5 Dependency Check N/A No CCTA Yes Not CCTA Western Electricity Coordinating Council

5 criteria used for review Criteria 1: Regional Significance Based on Voltage: 500 kV and above 200 kV or greater if “backbone”1 facility 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? 1 Backbone transmissions are facilities that provide network connectivity, typically 230-345 kV Western Electricity Coordinating Council

CCTA Process Demo: “Everett – Madison Transmission Project” Similar table to be created for all potential transmission projects This is the type of table we’d create for all potential candidates Highlighted fields will be considered in CCTA criteria/flow Western Electricity Coordinating Council

Ballot Results Neutral votes not counted In instance of a “tie”, this group to determine Western Electricity Coordinating Council

Western Electricity Coordinating Council 2024 CCTA Update Western Electricity Coordinating Council

Western Electricity Coordinating Council

Overall Feedback on Process CCTA 2026 Report by mid- Feb’ 2016 General RPCG consensus – Effective forum to give WECC feedback Review CCTA process for future improvements Criterion 3 and 4 to be reviewed and/or refined in future planning cycles Definitions Thresholds 2 / 3 hour RPCG meeting prior to late Summer TEPPC meeting Western Electricity Coordinating Council

Western Electricity Coordinating Council Acknowledgements RPCG membership – 7 month process. Gary DeShazo – Chair Jeff Hein – Vice Chair Colby Johnson and Jon Jensen – SAP team WECC – IT (Taylor A) and Business Services – Project Portal and 2026 CCTA voting survey Non-RPCG TAS-TEPPC members Western Electricity Coordinating Council

CCTA Team Contact Information Vijay Satyal – RPCG Liaison vsatyal@wecc.biz Colby Johnson – Assoc. Planning Engineer cjohnson@wecc.biz Western Electricity Coordinating Council