Electric power generation is the second-largest category of greenhouse gas emissions in California, next to transportation. California's administration, legislature, and energy regulators have adopted aggressive targets for renewable energy due to heavy reliance on natural gas as a fuel for electric generation, which will result in profound changes in markets and system operations. The growth of renewable in-state generation involves an increasing reliance on intermittent, often remote resources, which requires new transmission and increases ancillary service requirements. To the extent that achieving California's renewable energy goals requires imports of intermittent resources, new challenges emerge for coordination among system operators throughout the western states. New reliance on demand response and energy storage technologies are important contributors to solving these issues.