Over the past year and a half, a team of more than 100 Cal Poly students has worked to build a home that would enable the owner to pay no electricity bills, make water use efficient and have power left over to run an electric car.
Such homes are the wave of the future in California, which has a state policy goal of achieving “net zero” residential building standards by 2020 — meaning that newly built homes would supply all their own energy needs over the course of a year through onsite renewable energy, such as solar power.
The Cal Poly INhouse project is a 1,000-square-foot home with a 700-square-foot patio that features creatively designed bifacial solar panels with energy-absorbing cells on both the top and bottom of the panels. The panels not only take in sunlight from above but collect rays that are reflected off the deck from below.
The home also maximizes water use with a roof that redirects storm water runoff and a system that cleans and recycles graywater.
“INhouse goes to show that in order to live sustainably, there are a couple of key things you need, but you don’t have to make comfort sacrifices or completely change your lifestyle,” said Alyssa Parr, a co-project coordinator.
The students from 12 different majors at Cal Poly — including architecture, engineering and business — will truck the home to Irvine in four sections to compete in the national Solar Decathlon competition from Oct. 8-18.
The university last competed in the event, held every two years by the U.S. Department of Energy and the National Renewable Energy Laboratory, in 2005. Cal Poly placed third overall and currently displays that 2005 home on campus near the university’s architecture classrooms.
The team will be judged in 10 categories — architecture, market appeal, engineering, communications, affordability, comfort zone, appliances, home life, commuting and energy balance.
Cal Poly’s team has raised $520,000 in cash and donated materials, and expects to meet its goal of $650,000 by the start of competition.
The home has cost more than $350,000 to build; the additional funds will be used for transporting the structure and for hotel and other costs related to attending the competition.
In addition to a $50,000 grant from the Department of Energy, the team has received donated materials and construction help from multiple companies. Numerous university alumni, parents and friends have pitched in.
Sandy Stannard, a faculty adviser and architecture professor at Cal Poly, said that homes such as the one Cal Poly has designed and built aren’t that much more expensive than homes that aren’t energy efficient.
“So much of this is in the design,” Stannard said. “If you use a smart design that creates less reliance on heating and cooling, you can save a lot of energy because you don’t need to turn on the air conditioning or heater.”
Stannard said homes can be designed so resourcefully that at times they’re contributing energy to the grid that provides power statewide.
Beyond the solar panels and water systems, the home features redwood screening, decks and planters; bamboo interior flooring and cabinetry; and kiln-dried lumber with a low moisture content used for framing. Kiln-dried wood prevents mold and mildew.
“People have put an incredible amount of effort into this,” Parr said. “Students have worked day and night on the side just to keep things moving, hold meetings and meet deadlines. We’ve learned a lot, and we want to teach people a lot about what we’re doing.”