California has enacted ambitious goals for reductions in energy consumption and greenhouse gas emissions.  As part of an effort to better understand the impact of potential policies that may be used to reach these goals, this talk will describe work in progress to implement a model of the California energy system embedded within the GCAM (formerly MiniCAM) national and global integrated assessment  model.  This effort will result in a consistent model of the California energy system that is subject to consistent boundary conditions provided by the GCAM representation of the national and global energy systems and climate policies. Some issues specific to modeling the California energy system will be discussed, including building equipment efficiency and electricity trade.