The lithium-ion rechargeable batteries currently found in mobile phones, cameras and other consumer electronics are about to power entire homes. The first battery-operated houses are expected to be available for sale in Japan later this year.
At first glance, Daiwa's battery-operated house, with its rooftop solar panels, appears quite conventional.
But inside, this 2600 square foot home in Saitama near Tokyo quickly reveals itself to be a model in energy efficiency.
Daiwa calls it the Eco-house. It's connected to the grid, but is designed to provide it's own electricity for 14 uninterrupted hours each day. The difference between this and other solar powered homes, is the rechargeable lithium-ion battery that stores the electricity generated each day by the rooftop panels.
The power is distributed throughout the house by a centralised computer system which also keeps the home-owner informed of daily energy useage. Daiwa's Saeki Yoshinori says the system also offers energy saving suggestions.
Saeki Yoshinori, General Manager of Daiwa House Industry Co. Ltd. said "Advised by this monitor, residences can choose whether they're going to sell the stored electricity to the local grid or use it up in the house to reduce CO2."
The company believes it's energy management system will reduce carbon dioxide emissions by 65 percent. And as the technology improves, it says household electricity bills will
disappear entirely. At a cost of more than $600, 000 however, the house is not cheap. But Daiwa says the price of the technology will come down over time and that power storage and management will save homeowners money in the long run.
Saeki Yoshinori said "By enhancing the electricity storing technologies, we would be able to make this house fully self-sustainable with the energy generated in the house in the near future."
Daiwa's Eco-houses are expected to go on sale by April next year.