In a historic move, California has become the first state in the country to require solar panels on nearly all new homes.

On May 9, 2018, the California Energy Commission (CEC) unanimously approved standards that, among other things, mandate the installation of solar energy systems on all new residences and major home renovations on buildings under three stories, starting on January 1, 2020. In the event the building is not suitable for a rooftop solar array, the standards require that the homes have access to community solar or offset energy usage through additional efficiency gains, while some homes may be exempt entirely.

The standards were approved as part of a broader update to the Building Energy Efficiency Standards, which are a part of the state’s energy code. Such efficiency standards also apply to everything from current ventilation systems to indoor air quality. California updates the efficiency standards every three years.

“This is an undeniably historic decision for the state and the U.S.,” said Abigail Ross Hopper, president and CEO of the Solar Energy Industries Association. “California has long been our nation’s biggest solar champion, and its mass adoption of solar has generated huge economic and environmental benefits, including bringing tens of billions of dollars of investment into the state.”

The CEC estimates that the standards will provide homeowners with a net savings in their electricity bills of about $40 per month.

For further information on the topic, click here to see the CEC’s press release.