It’s A Beautiful Day In The Net-Zero Neighborhood
Net-zero homes are homes that are so energy efficient that the homeowner only has to add a renewable energy source, typically solar, to enable the building to generate as much energy as it uses. Some home builders have found their niche in building energy-efficient homes and have scaled up to building net-zero neighborhoods. This is true in California, partly due to new targets. The California Energy Efficiency Strategic Plan aims to have 100% of all new homes in the state be zero net energy – ZNE, as the state calls it – by 2020.
Net-zero neighborhoods are possible because they can be built in a way that is relatively affordable and also because they do not negatively affect the electric grid. That’s according to research from the Electric Power Research Institute (EPRI). The independent, nonprofit organization, which has offices in Palo Alto, Calif., and other cities, recently took part in a pilot project in Fontana, Calif. The project focused on 20 new suburban homes in a subdivision, called Sierra Crest, built with energy-efficiency features such as LED lights, advanced water heaters, dual-pane windows and more.
Ram Narayanamurthy, technical executive for energy utilization at EPRI, says the research was twofold. One goal was to see whether it would be feasible economically to scale up to a net-zero neighborhood. It was important to look at home buyers who can afford regular homes, not the more upscale, feature-rich custom homes.
“You want to work with real people that are buying homes, not just energy enthusiasts,” says Narayanamurthy, who was also the project manager at Fontana. “These are normal homes, 1,900 to 2,900 square feet, and the U.S. average is 2,400 square feet for new homes.”
The home buyers got a slight price break because they allowed EPRI and the project partners, builder Meritage Homes and the California Public Utilities Commission, to examine the homes’ energy use and grid integration. The homes have all been built, and the first occupants moved in by March of this year.
One of the barriers to buying a net-zero home, much less building a net-zero neighborhood, was cost.
“The cost of PV is a chief concern builders have right now in trying to get to net zero,” Narayanamurthy says. “It does increase the first cost. The question of affordability comes in. If people qualify for a certain price, does it push people out of being able to afford new homes?”
The second goal was to see how the homes would affect the local distribution grid. Narayanamurthy says EPRI is still working with Southern California Edison to measure grid impacts. The homes use solar, which has its own issues with backflow into the grid, but these homes are extremely energy efficient, so there is a reduced amount of peak load that the homes pull from the grid, he says.
“The goal is to find the balance point between energy efficiency and solar,” he says. “When we get to 2020 in California, solar is probably going to be the most prevalent local generation source.”
All 20 of the homes at Sierra Crest have SunPower rooftop solar panels, or will have them completed soon. SunPower is working with Meritage Homes on other net-zero neighborhoods. One that is coming soon is Meritage Homes Encanto in Southern California. Also, at The Cannery, a mixed-use community that The New Home Company built on the former Hunt-Wesson tomato cannery site, residents can upgrade to net-zero living, including with SunPower solar.
