As cartoonist Walt Kelly's character Pogo said, “We have met the enemy, and he is us.” Indeed two major sources of U.S. CO2 emissions are cars and homes—most of us drive, and we all live in homes—cars and homes account for 44 percent of U.S. greenhouse gases.
Honda, known for cars, is making its mark in homes with the opening of the Honda Smart Home US on the West Village Campus of the University of California, Davis. The Honda Smart Home saves more than 11 tons of CO2 compared to its conventional-home cousins.
Intelligent-home management is part of the environmental savings: The Honda Home Energy Management System (HEMS) “maximizes the home’s energy efficiency while communicating with the electric utility to improve grid stability.” The home also supasses California’s 2020 target for net zero energy residential consumption.
The home’s resident will also drive the Honda Fit EV (electric vehicle).
The home produces more energy on-site from renewable resources than it annually consumes.”Honda Smart Home is expected to generate a surplus of 2.6 megawatt-hours of electricity over the course of a year, while a comparable home will consume approximately 13.3 megawatt-hours. This results in a net offset of nearly 13,100 pounds of CO2 per year, even when taking into account California’s relatively clean electricity.”
The home is also three times more water-efficient than a typical U.S. home, a great feature, especially now that California has declared drought measures. The home showcases Honda’s vision “for sustainable, zero-carbon living and personal mobility.” The home will function as a living laboratory. It took roughly a year to complete the fully-furnished home, which will now serve as a residence for a person selected from the Davis community.
The West Village neighborhood, where the home is located, “is the largest planned zero net energy housing development in the United States,” It opened in 2011 and is home to the “university’s internationally-recognized research centers focused on energy efficiency, sustainability and transportation.”
Honda’s HEMS is the heart of the home. Their “proprietary hardware and software system ... monitors, controls and optimizes electrical generation and consumption throughout the home’s microgrid”—its circulation system. A 10kWh battery in the garage uses the same lithium-ion-cell batteries that power the Fit to save the energy produced by solar panels on the 9.5kW photovoltaic (PV) system. Storing power produced during daylight, allows the home to operate at night with little to no extra power needed from the traditional electric grid. Because most people work or attend school outside the home, peak demand for most homes is after dark. “HEMS leverages the battery to balance, shift and buffer loads to minimize the home’s impact on the electric grid.” The house also feeds power into the grid. HEMS will enable Honda to “evaluate the second life, or re-use, of EV batteries in grid applications, home-to-grid (H2G) connectivity and other concepts.”
The home also features geothermal radiant heating and cooling with eight 20-foot deep boreholes that help the home use the earth’s stable temperature and radiant floors and ceilings to keep the home comfortable throughout the year.
Cement, “concrete’s glue,” Honda says, is the largest factor that accounts for the about five percent of global man-made CO2 emissions from concrete. Possolan, a naturally occurring material, replaces half of the cement that would otherwise be used. Post-tensioning the slab also requires less cement.
Inside, LED lighting provides illumination at night. Honda worked with researchers from the California Lighting Technology Center to explore new circadian color control logic that mimics natural shifts in daylight that occur from morning to night. Amber hallway lights, for example, provide enough light to navigate halls during the night, without altering night vision. The result is that people can easily go back to sleep after waking in the night. Blue-rich light during the day, on the other hand, “helps put body and mind in an alert and energetic state.” At night, blue-light disrupts sleep and is why sleep experts advise people to stop using all electronic devices with screens that emit blue light or to put filters over the screens to change the light color.