Multi-Year Analysis of Renewable Energy Impacts in California: Results from the Renewable Portfolio Standards Integration Cost Analysis; Preprint

California's Renewable Portfolio Standard (RPS, Senate Bill 1078) requires the state's investor-owned utilities to obtain 20% of their energy mix from renewable generation sources. To facilitate the imminent increase in the penetration of renewables, the California Energy Commission (CEC), in support of the California Public Utility Commission (CPUC), initiated a study of integration costs in thecontext of RPS implementation. This effort estimated the impact of renewable generation in the regulation and load-following time scales and calculated the capacity value of renewable energy sources using a reliability model. The analysis team, consisting of researchers from the National Renewable Energy Laboratory (NREL), Oak Ridge National Laboratory (ORNL) and the California Wind EnergyCollaborative (CWEC), performed the study in cooperation with the California Independent System Operator (CaISO), the Pacific Gas and Electric Company (PG&E), and Southern California Edison (SCE). The study was conducted over three phases and was followed by an analysis of a multi-year period. This paper presents results from the multi-year analysis and the Phase III recommendations.