The Key to the Battery-Powered House

Without a way to store their power, no number of solar panels will free a home from the electrical grid. Researchers at Utah-based Ceramatec have developed a new battery that can be scaled up to store 20 kilowatt-hours–enough to power an average home for most of a day. An easy sell for solar users, but it could also allow the grid-bound to stockpile energy during less expensive off-peak hours. The new battery runs on sodium-sulfur — a composition that typically operates at greater than 600 F. Sodium-sulfur is more energetic than lead-acid, so if you can somehow get it to a lower temperature, it would be valuable for residential use, Ralph Brodd, an independent energy conversion consultant, says