Energy efficiency standards are among the most mundane things to consider when planning green residential buildings powered by solar.
Yet California’s latest update to its Title 24 requirements, which mandates that residential buildings be zero net energy by 2020 and commercial buildings do so by 2030, has complicated even further the process for installing solar. This seems especially true for multi-unit affordable housing complexes, which battle greater energy loads in proportion to more limited roof space — and stringent government funding requirements.
Since the standards went into effect on July 1, companies such as Promise Energy and Everyday Energy, which specialize in solar for low-income and affordable housing—are playing key roles in helping architects and developers keep an eye on these requirements and make sure they comply with these state regulations.
“Where the rubber meets the road is where you have building policies and code trickling down … and the market that needs to implement them is too busy doing business as usual,” said Adam Boucher, Promise Energy CEO. “Promise Energy has become experts in meeting those codes and connecting the dots because our market relies on them.”
There’s a number of examples that illustrate the issue when applied to affordable housing developments, according to Andy Mannle, Promise Energy’s vice president of strategic development.
Multifamily unit buildings have more energy needs due to a greater number of residences — yet have a smaller roof space to generate that amount of solar energy per family, he said.
Developers, architects and others who take on publicly funded affordable housing complexes also must adhere to strict deadlines and budgets.
And because the buildings need to last a long time, they are required to be even more energy-efficient than current building code, according to Mannle, so that they don’t get out of date.
“So it’s not enough to say that you want a super-green building,” said Mannle. “You need to get the whole team together early on in the process and get up to speed on the nuances of the solar system so that the design is developed from the roof down.”
That’s what firms like Promise Energy do on affordable housing projects. During the design and construction process, they keep an eye on anything that might interfere with what’s needed to make a solar system work — such as repositioning or suggesting another location of air vents that are tall enough to introduce shading to solar PV panels.
Mannle says that constantly changing codes, solar equipment technology and pricing ratchet up the complexity even more.
And the state’s new software used to calculate whether a building meets its Title 24 energy efficiency requirements has made it more difficult for energy consultants to maximize a building’s efficiency, according to Nehemiah Stone, an energy consultant with expertise in multifamily units.
“In past, [the energy consultant] used to be able to do 5 to 6 barometric runs in 15-20 minutes,” he said. “Now, one run takes 20 minutes to complete. As a result, you can’t give the architect and developer the same level of expert advice.”
Solar apartments photo courtesy of Gish Apartments by way of USGBC.