Back in 2013, Honda worked with UC-Davis to launch a smart home project that would consume zero net energy. It was a bold experiment and a technical IoT marvel. Human dwellers occupied the home along with over 230 built-in sensors. Both provided a wealth of data and feedback that yielded several surprising results. Foremost was the importance of collecting data in a real-life environment, analyzing it and then acting on that analysis to try out new conditions and improved technologies. Six years later, the data and details of this project have been compiled into 5 key lessons learned, which will be reviewed shortly.
First, a bit of background on the beginnings of this project are needed. Before the smart house could be built, all aspects of its design, operation and sustainability had to be understood and balanced. Even the home’s site selection was chosen to ensure the best exposure for the rooftop solar panels. Every detail of the overall design was similarly reviewed with a collaborative team consisting of an architect, HVAC designer, electrical/electronic and mechanical engineers, construction certification members, and Honda experts. Heating, cooling, lighting, operation of appliances, and water reuse activities were designed together to support zero net energy consumption while allowing the occupants to live comfortably.
From the human occupant perspective, the goal was not to significantly change specific behavior patterns. For example, if the occupants had to wash dishes, shower or run laundry, then the home had to respond immediately. If the timing of these activities required excessive use of the energy grid, then the Honda-designed Home Energy Management System (HEMS) would intervene to allow them to continue their daily routine, as well as return extra power to the grid if possible.
The HEMS, located in the smart home’s garage, was a hardware and software system that monitored, controlled and optimize electrical generation and consumption throughout the home’s microgrid. It stored solar energy during the day and was capable of “listening” to the grid to ensure power was only drawn at the most carbon-efficient times.
![]() |
Image Source: Honda Smart Home System – HEMS and EV in Garage |
The project has proven to be a success. Located on the West Village campus of the University of California, Davis, the home as annually produced more energy from renewable sources than it consumes annually, including enough energy to power smart car (e.g., a Honda Fit EV) for daily commuting. Energy management systems were essential to maintaining efficient heating, cooling and lighting systems within the house.
Other sustainability factors, such as water-use, were also managed and controlled. The result a home with three times more water-efficiency than a typical U.S. home.
Proof of the zero-net energy consumption is available from yearly data accessible to anyone on everyone on the download tab of the Honda Smart Home site.
![]() |
Image Source: Honda Smart Home – Data |