Because of such policies, the most populous US state has frequently been at odds with President Donald Trump's aggressive rollback of policies to combat climate change. According to the AP, the mandate still needs final approval from the state's Building Standards Commission, which will likely happen.
It cited Bob Raymer, technical director for the California Building Industry Association (CBIA), as saying that now 15% to 20% of new single-family homes have solar.
The rule will take effect in January 2020. They are collectively expected to reduce the state's greenhouse gas emissions by 700,000 metric tons over three years, a level equal to taking 115,000 cars off the road, according to state officials.
All told, the new code is meant to save Californians a net $1.7 billion on energy bills, while advancing the state's efforts to build-out renewable energy, the commission said.
Over the life of these new homes, residents could still see larger returns on their investments.
California is already ahead of schedule with its long-term energy goals: the California Public Utilities Commission reported that they will likely meet the 2030 goal 10 years ahead of schedule.
"Adoption of these standards represents a quantum leap in statewide building standards", said Robert Raymer, technical director for the California Building Industry Association.
California has struggled with an affordable housing crisis in recent years. The state's new rate structure beginning in 2019 also gives an incentive to use energy storage during high-peak times when prices will be vastly more expensive. Some economists say home and rent prices will continue to grow in 2018.
California, the most populous state, with almost 40 million people, has positioned itself as the nationwide leader on clean energy, pushing for more electric vehicles on the roads and lower emissions from homes and commercial buildings. But over the past decade, California has averaged less than half of that. The requirement would only apply to newly constructed homes, not existing ones, although many homeowners are choosing to install solar panels with the help of rebate programs.