California governor Jerry Brown has put the final rubber stamp on “landmark” legislation that mandates that 50% of the state’s electricity is from renewable sources, along with a raft of other measures aimed at meeting climate goals.

The governor signed the documents yesterday at an event held at the Griffith Observatory, which overlooks Los Angeles. The bill, SB350, demands a doubling of energy efficiency in buildings in terms of savings, as well as an increase in the Renewables Portfolio Standard of the state from 33% to 50% by 2030.

“California has taken ground-breaking steps to increase the efficiency of our cars, buildings and appliances, and provide ever more renewable energy. With SB 350, we deepen our commitment,” Brown said.

Some of the original aims of the bill were however tempered from earlier proposals. The bill was amended to drop a requirement to halve petroleum use for mobility, for instance.

Additionally, while solar groups including the Solar Energy Industries Association (SEIA) greeted the bill as a “huge win”, the group’s vice president has said that in order to meet greenhouse gas (GHG) emissions’ targets of 40% reduction in 15 years’ time, even more renewables would be required beyond the RPS targets.

“Rising sea levels will impact homes, businesses, infrastructure, our national security, and our economy. That's why SB 350 is so important to our future. With SB 350 California is leading by example. It sets the course for our state, for the nation and for the world. There will come a time when climate change deniers finally pull their heads out of the sand. When that day comes, they can look around and see that California will be in better shape because we put SB 350 in place today,” Toni Atkins, speaker of the California State Assembly, said.

Brown also signed a pact with Chilean president Michelle Bachelet at the end of last month making a mutual commitment to combating climate change.