Late last month, Nissan announced that starting in April its new electric car, the Leaf, would be used as an emergency power supply for a new office-condominium high-rise in Shinjuku managed by Sumitomo Real Estate. In the event of a disaster that resulted in a power failure, Leaf cars could be connected to the building's electrical system through outlets specially installed for recharging electric vehicles and then the cars' stored power could be used to supply electricity to the building for up to 42 hours for emergency services such as recharging cell phones and illumination. As a side note, the building also has a special hall that can be converted into a shelter for people in Tokyo who cannot return home during a disaster.

Though this is just a corollary benefit of the Leaf, Nissan's announcement stresses the idea that electric vehicles could offer a wider range of purposes than just mobility. A number of new housing communities that are being developed with "smart grid" technologies have homes with EV charging stations. As with the Sumitomo building, these stations not only provide electricity for charging the battery of an EV, they also accept electricity from an EV that can be used in the home.

Such news is being stressed as more carmakers enter the EV field. Mercedes Benz Japan said it will start selling its own electric car, Smart, as early as August due to consumer demand. It will be the first foreign EV sold in Japan. At the moment the price hasn't been determined, but an executive with the company has said it will be competitive with domestic EVs. The Leaf's sticker price is about ¥4 million, but with the restart of the government's eco car subsidy, a consumer could take it home for about ¥3 million. The Mitsubishi EV, the MiEV, is even cheaper. After subtracting the subsidy it would cost a little less than ¥2 million.