Assumptions for the 2027-2028 TPP

 

The Integrated Resource Planning (IRP) process develops a resource portfolio(s) annually as a key input to the California Independent System Operator's (CAISO) Transmission Planning Process (TPP) base case studies, which includes a reliability base case portfolio and a policy-driven base case portfolio.  The California Public Utilities Commission (CPUC) may also transmit additional resource portfolios as inputs for sensitivity studies that test the implications of various policy futures.  This page contains documentation relevant to the development and mapping of resource portfolios for the 2027-2028 TPP.

Webinar – 06/16/2026 – IRP MAG Webinar on Potential Updates to the Busbar Mapping Methodology

  • Objectives
    • Provide an overview of the busbar mapping process and its role in the TPP
    • Familiarize stakeholders with the updates to the criteria and the criteria alignment thresholds. 
    • Give opportunity to stakeholders to ask questions and provide comments on the busbar mapping methodology and the proposed criteria. 
    • Request stakeholders’ informal written feedback to be incorporated in the final updated methodology
  • Noticing Document 
  • CPUC slides
  • CEC slides (TBP)
  • Webinar Q&A
  • Webinar Recording