Tiny Battery Traps Solar Power To Run An Entire House

(this was mailed to me by a friend)

A small disc could be the solution for the efficient and cheap storage of the sun’s energy. A Utah-based company has found a new way to store solar energy – in a small ceramic disk which can store more power for less. Researchers at Ceramatec have created the disk, which can hold up to 20-kilowatt hours, enough to power an entire house for a large portion of the day.

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.

Ceramatec’s new battery runs at less than 200°F. The secret is a thin ceramic membrane that is sandwiched between the sodium and sulfur. Only positive sodium ions can pass through, leaving electrons to create a useful electrical current.

Ceramatec says that batteries will be ready for market testing in 2011, and will sell for about $2000. The disk has not yet been manufactured for residential use, but the creators have spoken  optimistically about the possibility.

The convergence of two key technologies — solar power and deep-storage batteries — has profound implications for oil-strapped the US.

“These batteries switch the whole dialogue to renewables,” said Daniel Nocera, professor of energy at the Massachusetts Institute of Technology who sits on Ceramatec’s advisory board. “They will turn us away from dumb technology, circa 1900 — a 110-year-old approach — and turn us forward.”