The rooftop solar array is about twice the size of one typically found on a comparable suburban home. The amount of electricity generated by the solar panels and stored in the battery pack allows the home to operate independent of the power grid, if necessary.

Image A homeowner can use an iPad to wirelessly control and monitor the solar home’s functions. Credit... Thor Swift for The New York Times

The home sends excess electricity to the grid. And if the utilities become overloaded, say, in the summer when temperatures spike and everyone turns on their air-conditioners, the local electricity provider can send a signal directing the home to send solar electricity to the grid to help avert blackouts.

A similar size home would consume 13.3 megawatt-hours of electricity a year while the smart home would generate an estimated surplus of 2.6 megawatt-hours annually, according to Honda.

“We can get our carbon footprint below zero,” said Michael Koenig, the project leader for the Honda Smart Home, as he stood in the living room of the airy, light-filled house while a rerun of “McHale’s Navy” played on a large flat-screen television embedded in a wall.

He held an iPad that wirelessly controlled all the home’s functions, from lighting to the power systems, and that showed the house generating 4.2 kilowatts of electricity on a partly sunny morning while consuming 0.84 kilowatt.

“The system will calculate the household electricity load for the day based on the home’s history as well as the expected solar output and it’ll only buy power at the lowest price,” Mr. Koenig said.

The Honda Fit EV in the garage has been modified to accept energy directly from the solar array, too.