Last Updated May 9, 2018 4:19 PM EDT
SACRAMENTO, Calif. - California may start requiring solar panels on new homes and low-rise apartment buildings built after 2020, the first such mandate nationwide and the state's latest step to curb greenhouse gas emissions.
The California Energy Commission on Wednesday approved a requirement for solar panels on new homes starting in 2020. The commission estimates they would add an average $10,500 in construction costs for a single-family home but generate about $16,000 in energy savings. The standards also include requirements concerning ventilation and indoor air quality.
The measure now moves toward final approval later this year by the state's Building Standards Commission.
The Energy Commission vote coincides with the release of a report from the California Environmental Protection Agency that details the many ways climate change is affecting the state, leading to increases in air temperatures, larger wildfires and frequent dry years.
California has pushed for more electric vehicles on the roads and fewer emissions from residential and commercial buildings, positioning itself as the nationwide leader on clean energy, pushing.
"This is going to be an important step forward for our state to continue to lead the clean energy economy," said Kelly Knutsen, director of technology advancement for the California Solar and Storage Association.
Few industry groups outwardly oppose the plan after working for years with the commission to shape the regulations. But Republican legislative leaders said Californians can't afford to pay any more for housing in the state's already extremely expensive market.
"That's just going to drive the cost up and make California, once again, not affordable to live," said Assemblyman Brian Dahle, the chamber's Republican leader.
The state updates its building codes, including energy efficiency standards, once every three years.
The requirement does include exceptions when solar panels aren't feasible -- such as on a home shrouded in shade -- or cost effective. Installing storage batteries or allowing community-shared solar generation are available options. 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.
The California Building Industry Association supports the solar panel requirement after years of working with the energy commission to refine it, said Robert Raymer, the association's technical director.
"On the one hand, we would prefer that this had been put off for a few more years, but the fact is that the California Energy Commission has been working on this, with us, for the past 10 years," he said. "We know this is coming, we did everything we could to push down compliance costs and increase design flexibility."
About 117,000 new single-family homes and 48,000 multifamily units will be built in 2020, the commission estimates.