Assumptions for the 2025-2026 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 2025-2026 TPP.