The governor of California has signed an ambitious climate change bill that aims to increase the use of renewable electricity and make buildings more energy efficient.
"California has taken groundbreaking steps to increase the efficiency of our cars, buildings and appliances and provide ever more renewable energy," Governor Jerry Brown said at the signing ceremony.
"With SB 350, we deepen our commitment."
The bill aims for California to generate 50 percent of its electricity from renewable resources such as wind and solar energy by 2030.
It also calls for buildings in the West Coast state to become twice as energy efficient by 2030.
"Today, California is laying the groundwork for a healthier and sustainable future for all of our families," state senator Kevin de Leon said.
"We are showing the world through innovation how we can transition and increase access to renewable energy while cleaning up the air we breathe, especially in our most polluted communities."
The legislation had suffered a major setback last month when it had to be amended to remove a component that would have required reduced petrol consumption on California roads.
Oil companies had opposed the measure, launching a fierce lobbying campaign that included television and radio ads.
California is the largest US state by population – the third largest state by area – and often is seen as a trendsetter for the rest of the country.