By Lacey Johnson and ClimateWire March 7, 2012
Nearly 40 percent of the nation’s energy is consumed by homes and commercial buildings, which means that making them more efficient would not only save money but also drastically reduce carbon emissions. So a handful of builders are taking the idea one step further: Why construct a building that uses less energy when we can make one that uses no energy at all?
That’s the philosophy behind “net-zero” buildings, and they have been springing up all over the country in recent years. By the purest definition, a net-zero building produces all the renewable energy it needs on site, drawing no more power from the grid than it gives back.