San Francisco passes mandate for rooftop solar in new buildings


Under the new law passed, new residential and commercial buildings are required to have rooftop solar, either solar electric or solar water heating, states

[quote] The new solar bill was passed through a unanimous vote by the city’s Board of Supervisors. The mandate is an extension of an existing regulation that necessitated new building projects to allocate 15% of a building’s roof as being “solar ready”. This means that the roof area would be unshaded and cleared of any obstructions for effective solar power generation and heating.

Scott Wiener, a member of San Francisco’s Board of Directors, said: “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.

“Activating underutilized roof space is a smart and efficient way to promote the use of solar energy and improve our environment. We need to continue to pursue aggressive renewable energy policies to ensure a sustainable future for our city and our region.”

Rooftop solar

The new law states that 15% of new buildings’ surface area, will not only be reserved for solar, but it is necessary “to have solar on it.”

According to the San Francisco Examiner, the Department of Environment applied the proposal to construction projects in the pipeline in the third quarter of 2014, to gauge the impact the mandate could have.

Based on the results of the small-scale trial where 200 projects that applied the law, the new ordinance was found to have the potential to avoid over “26,000 metric tons of carbon dioxide emissions per year.”

Prior to the new bill being passed, Wiener introduced The Better Roof program, which could increase the current 24.8 MW of rooftop solar in the city by an additional 7.4 MW. The added solar energy is said to have the potential to provide electricity to about 2500 homes in the city annually.

Barry Hooper, the Department of Environment Green Building Coordinator, said that “100 percent renewable energy depends on both development of renewable energy resources and continued improvement in energy efficiency.

“This ordinance represents one more straightforward and pragmatic step toward that goal. It’s been demonstrated as being highly cost effective.”


Image credit: