San Francisco pushes a new California law even further. California currently requires all new buildings under 10 floors to have 15% of their rooftops designated as solar-ready, which means they must be in the sun and wired for future use. Yesterday, the San Francisco Board of Supervisors one-upped the law with a requirement that the buildings actually have solar, not just be solar-ready.

“By increasing our use of solar power, San Francisco is once again leading the nation in the fight against climate change and the reduction of our reliance on fossil fuels,” Supervisor Scott Wiener said in a statement. “Activating underutilized roof space is a smart and efficient way to promote the use of solar energy and improve our environment."

The new legislation will go into effect in January 2017. Wiener says the Board of Supervisors is also looking at alternative requirements such as living roofs if developers aren't keen on installing solar.

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