The minimum amount of solar power required by the new standards wouldn't be enough to meet all the needs of most homes.
The proposal before the commission seems to address one of the state's most pressing issues - reducing greenhouse gas emissions - while exacerbating, at least in the short run, another: the increasingly high cost of housing.
"This will be nothing short of historic for our state and for our country", said Bernadette Del Chiaro, executive director of the California Solar & Storage Association, an industry group. The California Energy Commission hearing room was packed full on Wednesday as the commission voted unanimously in favor of the proposed rule.
New home builds account for about one percent of the state's total residences per year, according to Delforge, so don't expect to see swaths of solar panels popping up on roofs across the state just yet. "Until we tackle that problem, doing things like requiring solar panels on new construction is a band aid, ' he said".
The new standards "focus on four key areas: smart residential photovoltaic systems, updated thermal envelope standards (preventing heat transfer from the interior to exterior and vice versa), residential and nonresidential ventilation requirements, and nonresidential lighting requirements", said California Energy Commission spokesperson Amber Beck.
The rules now go to the state Building Standards Commission, where they were expected to easily win approval.
As of the end of 2017 only 20% of new homes in California was provided for the installation of solar panels.
All the new buildings below 10 stories in San Francisco are already mandated to fit the solar panels. A National Association of Realtors survey for the fourth quarter of 2017 listed four California markets among the nation's five most expensive. It goes into effect January 1, 2020, and includes all condominiums and apartment buildings up to three stories high.
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The mandate is part of California's "Energy Efficiency Strategic Plan", which includes the goal that both residential and commercial construction be zero net energy by 2030-meaning the buildings' annual energy usage is either less than or equal to the renewable energy generated onsite.
In fact, the state itself generates so much solar and wind power that it must sometimes halt production at some facilities or give the electricity away to other states to avoid overloading the electric grid.
The Energy Commissioners is taking a significant step to continue its push for lowering greenhouse gas emissions - using the sun as its saver.