The California Energy Commission is on the verge of adopting changes to the 2008 Building Energy Efficiency Standards (title 24). From American Architectural Manufacturers Association:

“The proposed 2013 standards focus on several key areas to improve the energy efficiency of newly constructed buildings (as well as additions and alterations to existing buildings), help reduce electricity demand reductions during critical peak periods and enable simple and efficient future solar system installations. This is expected to save California residents and businesses hundreds of millions of dollars in energy costs over the next decade, as well as benefit the environment.”