Net-zero energy homes

Net-zero homes, as the name implies, produce as much energy as they consume, but remain a sliver of the new home construction market. Estimates put present-day net-zero homes in the U.S. at 5,000 though California is expected to add the greatest number in the near future. Though California has taken greater steps in recent years with a new requirement in December that accelerates the adoption of the net-zero approach stipulating that “most new homes and multi-family residential buildings up to three stories high to include solar rooftop panels beginning in 2020.”California’s approach is the first time any state has built this type of requirement into the building code.

The two methods for reducing the carbon footprint on the electric grid according to Charles Kibert, professor of Florida’s College of Design Construction and Planning beyond just zero-energy homes are a low-carbon grid and better renewable energy storage. The cost of storage solutions like Tesla’s Powerwall and offerings from Germany’s Sonnen (now acquired by Shell) may be dropping but are still not a mainstream option for most; which is why being connected to the grid remains imperative. It’s also why the utility industry is watching net-zero and home energy efficiency closely.

For utilities, the net-zero home could be an advantage particularly if net-zero homes have the means and intelligence, as part of a system, to be as energy-efficient as possible during times of peak demand on the grid. Net-zero or simply highly efficient building materials, coupled with behind the meter generation and storage could in theory bring greater stability to the grid. California’s net-zero experiment, both on the policy side (inside building codes) and the technology side (see the various building materials and hardware and software systems at work) will undoubtedly serve as a test bed that other states will draw upon.