A Honda–Not the car but the experimental house. When its solar panels make more energy than it consumes, it can power an electrical Honda pictured below.
With electricity it’s all about storage. That’s what a battery does. It stores electricity. The bigger the battery, the more electrical storage. The more advanced the battery’s storage technology, the more efficient the battery is. Nickel cadmium is not as efficient as lithium-ion but it’s cheaper. So anything that runs on a battery has to be re-charged by an available electric current. That current is typically supplied by an electric utility. Easy enough.
For alternative energy sources, like solar or wind, once the sun goes down or the wind stops, other sources are needed, especially if it’s to heat or cool your home. And vice versa for your car. Once the battery loses its charge, it needs more electricity. Car meet house; house meet car.
Now carmakers are coming up with a way to store that electricity generated by altnerative energy–car batteries–that can then be used for home electricity. Sound strange?
Honda is introducing an experimental house with technologies that allow the dwelling to generate more electricity than it consumes. Ford, Tesla Motors, and Toyota are developing similar technologies.
The Honda experimental home is a 1,944-square-foot dwelling with a 10 kilowatt-hour lithium-ion battery pack. A smaller version sits next to the electric Honda Fit parked nearby.
How does it work?
The home battery pack sits next to a bigger white box called the Home Energy Management System. It decides when to tap into the 9,5-kilowatt solar panel array on the roof to charge the car’s battery. Otherwise it stores the solar energy for the home’s use.
When all is going well, the house is off the grid. The home can also send electricity to the grid.
Compared with a “normal” house, the experimental house with a smart battery and solar panel hook-up generates a surplus of 2.6 megawatt-hours a year versus consuming 13.3 megawatt-hours a year.
The Home Management System has to do a lot of calculations, though. It has to know what the load need is, when to send electricity to the car and what the weather is. The house also uses geothermal heating and cooling.
This is not a simple undertaking. Even the concrete is different. The Honda home uses pozzolan, a volcanic ash, to reduce the carbon footprint of concrete. And the L.E.D. lights have to be color-adjusted to mimic natural daylight and at night so they don’t bother the dwellers’ eyes with the deep blue hues that are really annoying, as anyone who has stareed into one of those L.E.D. headlamp lights.
Electric utilities have been slow to connect such syst3ems to the grid, arguing that homeowners could use batteries to store electricity when rates are low and sell it back when rates are high.
Cars that return electricity to the home or grid is on the drawing boards but not yet ready for prime time. But it’s coming, automakers say.
Batteries are one of the keys to the Internet of Things. In the meantime, cars and homes will make up a big piece of the puzzle and the attempts to decrease our carbon footprint and utilize alternative energy sources.
Here’s the piece in full by reporter Todd Woody: http://www.nytimes.com/2014/03/25/business/car-companies-take-expertise-in-battery-power-beyond-the-garage.html