Photovoltaic panels generate all the home’s electricity, sending surplus energy back to the grid. All the home’s systems—hot water, HVAC, and radiant heating—are integrated, electric-based, and powered by the PV panels on the roof. The only use of natural gas is at the cooking range, which draws from a 50-gallon propane tank. With the exception of the propane tank, the home is net-zero in terms of its energy consumption. Photographer: Matthew Millman