The California mandate requiring solar be included with all new construction goes into effect January 1, 2020. Solar Energy Industry Association’s director of codes and standards, Joe Cain, spoke on the topic during a session September 24 at Solar Power International, going into the details of the legislation and how similar measurements are being considered elsewhere.
During that talk, Cain suggested that California as a state is a proper testbed for solar on all new construction, due to the state’s varying climate zones.
“If you look at what’s happening nationally, in the national conservation code, there are deeper climate zones,” he said. “But when you look at a California map compared to the national map, really, we have zones in California that are similar to all other zones in the U.S. So, solar’s possible anywhere in the U.S.”
California has the only statewide legislation requiring solar be built on all new construction. Some cities in the state have started acting on the mandate earlier than the January 1 start date, Cain said.
However, one east coast city predates California’s 2020 solar mandate: South Miami, Florida. The city’s commission passed the measure in July 2017 and it went into effect two months later, according to the Miami Herald. New South Miami homes now must have 2.75 kW of solar per 1,000 sq ft of the building and must be included with renovations replacing or expanding a home by 75%.
Massachusetts is considering a similar trajectory as California with two bills that were recently introduced mandating solar for all new construction projects on state-owned, commercial and residential buildings — or on renovations above $25,000.
“People are talking about a PV mandate and I’ve been reminded that it’s not really a mandate. This is a prescriptive requirement, not a mandatory measure by energy code in California,” Cain said. “In the mandatory measures, it’s not there.
The prescriptive measure in this context is a list of requirements for solar on new construction and it includes a formula to determine the minimum size of the system. However, those measures are somewhat flexible and can be supplemented with other energy considerations. Homeowners can decide to add extra insulation or install only energy-efficient lightbulbs.
“If you can get it to work, you can use no PV and all efficiency measures — but it’s extremely unlikely to work,” Cain said.
Installing battery storage with PV can also reduce the required system size. These additions are known as tradeoffs.
“Adding batteries gives you nominal flexibility to what you can design, and it will likely save you money because you can choose a cost-effective solution than if you cannot do any tradeoffs whatsoever,” Cain said.
Exceptions to the bill
There are six ways to be an exception to the California solar mandate, but a couple are standouts, Cain said. If a new building has too much shading or not enough roof space, then it can be exempt. But in those cases, there is the option to use offsite solar from community or shared solar projects. Installers will be tasked with receiving approval from the local energy commission if that’s what a customer chooses and the offsite solar systems must be available for inspection by a jurisdiction’s building department.
“But when I asked, ‘What was the proximity requirement?’ they said, ‘Well, we’re figuring it’s somewhere in the state of California,” Cain said. “As long as the bill credits are all worked out and it’s dedicated, you can still do that.
Municipal utilities in smaller California communities argued that since they offer cheaper energy rates than both larger utilities and putting solar on new homes, they should be an exception to the rule.
“Our big concern’s that they will come in and want an exception,” Cain said. “We’ve been going through a lot of considerations.”
There are 1.4 million new units built in the United States every year. It’s significant to install solar panels on just the new construction in territories that require it, Cain said.