Its electricity and water heating is wholly powered by photovoltaics, it uses recycled and energy efficient construction materials, and it is extensively equipped with water conservation equipment. Campaigners hope all new homes in California will be powered solely by renewable energy like the SOLARA development (Copyright Community HousingWorks) The SOLARA development in California, which officially opened last year, is what green campaigners hope will become the model for all new homes in the state. Last week a draft bill passed another hurdle in the California Assembly which environmentalists hope will bring this dream closer to being reality. The Residential Zero Net Energy Bill, which will require all new residential buildings to be net zero energy by 2020, was approved by the assembly's Natural Resources Committee. The bill, which was written by assembly member Lori Salda