In 2010, in the nippy environs of northeastern Canada, a family of six submitted to an experiment. Their task: spend one year living in one of the most energy-efficient homes built in North America. The house in New Brunswick looked like others except for the solar panels on the roof. But by year's end, there was a more substantial difference — it was the only house on the block with a nonexistent energy bill, according to the Atlanta Journal Constitution.
"The house we built generated enough electricity for two families," said Tom Black, vice president of Eco Plus Group USA, which partnered with Bosch to create the home.
Fast forward two years, and they have done it again, building the first Bosch Net Zero home in the United States at Serenbe in Chattahoochee Hills, near Atlanta. The house, through the use of geothermal heat and solar voltaic panels, is designed to generate more electricity than it uses. The excess energy is stored on the distribution grid of GreyStone Power Corporation, where it is redistributed as needed. At the end of the year, the series of energy credits and debits tracked by GreyStone should be at or near zero.
Net zero or zero net energy homes are among the latest buzzwords in green building. According to the U.S. Department of Energy (DOE), the term applies to any ultra-efficient home that uses comprehensive building science measures and energy-efficient components so most or all of the energy consumed annually can be easily offset. Homeowners are left with substantially reduced utility bills, as well as less noise, improved indoor air quality and durability.
Homes consume more than 20 percent of total energy used in the U.S., according to the DOE. As of May, more than 12,000 homes built by 250 builders around the country carry the DOE Challenge Home label, which indicates a home has been built to a set of specifications making it zero-net energy ready.
After an invitation by Gov. Nathan Deal to visit Georgia, Black was introduced to Steve Nygren, co-founder of Serenbe. When Black arrived at the 1,000-acre community and model for balanced development, he knew it would be the perfect place for the Bosch home.
At about 1,700 square feet, the bilevel three bedroom, two-and-a-half bathroom home features a number of Earth-friendly elements, including Forest Stewardship Council certified engineered hardwood floors, EPA WaterSense certified Toto plumbing and fixtures and Bosch appliances.
Bosch also created the suite of products that make the home a zero net energy house.
"It is hard to find a company that could make everything and would stay in business," Black said. Other companies, he said, could sell one aspect, but Bosch was able to provide a full system including 18 solar panels that react chemically with ultraviolet rays to generate electricity. The company also makes the geothermal pump, which heats and cools the house from below ground where the temperature is more consistent than the air used by traditional air pumps.
A good amount of the home's $499,000 price can be attributed to the geothermal heat pump. The higher the tonnage of the pump, the deeper its well needs to be, Black said, and digging wells is expensive. But a net zero system should pay for itself in five to six years, Black said, and federal and state tax credits help offset costs. As the trend continues, consumers may see net zero homes as low as $210,000, he said.
Already, Eco Plus — a company founded last year — has built 20 Bosch Net Zero homes in North America, with six in Georgia, including one more under construction at Serenbe.
"There are a lot of good technologies, but some are hard to live with," Black said. "This is what we have put together, and we are still perfecting it."
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