Detractors often say one of the big drawbacks to buying an electric vehicle (EV), such as the Nissan Leaf, is the lack of infrastructure. You still need to wire your home to charge the car's batteries and long-distance travel is dependent on recharging on the road. But what if the EV could become part of the electrical grid itself and even provide power to your home during blackouts?
Nissan is exploring that concept with a project in Japan called "Leaf to Home." It's essentially a "two-way" charging system, allowing the Nissan Leaf to be charged as usual—say, overnight when electricity is cheap and abudant—and then supply electricity from its battery back to the home when needed, such as during daytime hours when electricity is at its peak usage or during local power outages.
The system is being tested in Japan, which is still suffering from an energy shortage due to the March earthquake disasters. According to officials, the Leaf's 24 kilowatt hour (kwh) battery could store enough electricity to power a typical Japanese home for about two days. Alternatively, the Leaf could power a home for about two hours and still have enough juice to do some local drives.
Nissan hopes to have a commercial version of the Leaf-to-Home system ready for sale in Japan next year. Systems for Leaf owners in other countries, such as the United States, could follow, but would require adaptation to—and acceptance by—local power utilities.
Such mobile power storage ideas aren't new. Geeky greenies have been tinkering with such set-ups with plug-in hybrid cars and power companies have toyed with the idea as part of the development of a long-awaited "smart grid."
And while such ideas might make sense for hybrid cars, which can run their internal combustion engine to provide electricity, we'd question how useful this set-up might be for American Leaf owners.
According to the U.S. Energy Information Administration, the average U.S. household used 908 kwh of electricity per month, or about 30 kwh per day. That means the Leaf's battery—which in our experience routinely comes up short of its claimed 100-mile range — would just barely sustain a U.S. household during a day-long power outage.
Still, in an emergency or a summer power "brown out" where home air conditioners can draw a lot of power, this type of EV-to-home scheme might be appealing. What do you think?