ROLE OF RPS CALCULATOR IN >33% RPS STATEWIDE TRANSMISSION PLANNING? 1

Role of RPS Calculator - Background Assuming that the CAISO special study will explore potential transmission needed to facilitate a significantly higher amount of renewable energy, the RPS Calculator will need to generate the portfolios to be studied, as procurement to meet this goal has not yet taken place Due to declining procurement, a single “policy-preferred” portfolio is produced from the calculator for the LTPP-TPP process as the “base case” for the CAISO’s transmission planning, along with portfolios reflecting different procurement trajectories CAISO proceeds to develop its “policy-based” transmission plan based on a least-regrets approach and uses other policy portfolios to validate the least-regrets determination 2

“Role of Calculator” Roundtable Purpose: – Discuss the role the RPS calculator plays with regards to California achieving its renewable energy goals most cost effectively, with the least impact to the environment, and in a reliable manner Operating assumption for roundtable discussion: – Assume 50% RPS by 2030 for the purpose of this conversation – Parties should not consider the assumption to be the CPUC’s official position on a >33% RPS target – Incremental RPS generation would be studied as EO 3

Role of RPS Calculator - Questions  Given the much larger 50% RPS “net short”, should the CAISO separately study transmission needs based on multiple reasonably plausible patterns of development?  Should the CAISO Special Study focus on exploring potential >33% RPS transmission lines of least-regret?  If yes, how many and what type of portfolios should the RPS Calculator produce for the CAISO special study?  What changes, if any, are required to the interagency coordination and stakeholder processes? 4