But its inventor says what's inside the box can supply the world with clean, cheap energy, reports CBS News Correspondent John Blackstone.
Following its television Sunday, the Bloom Box at eBay's headquarters in San Jose, Calif.
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"The core of our technology is simply sand," Bloom Energy founder K.R. Sridhar said at Wednesday's unveiling.
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The sand is the raw material used to make wafers that can make electricity.
Bloom's fuel cell works like this: Oxygen is pumped in on one side and natural gas on the other. The two combine inside the cell to create a chemical reaction that produces electricity. No burning, no combustion, no power lines from outside.
Bloom's founder has persuaded some big names that by making them out of sand he can make fuel cells that are efficient and inexpensive.
"Will it work for 10 or 20 years without something going wrong? We'll find out," former Secretary of State, Gen. Colin Powell, a Bloom Energy board member, said Wednesday.
Bloom Energy says the best proof that its fuel cells work is in the ones already working like those at eBay's headquarters, but Bloom is not the only company pursuing this kind of technology.
One of Bloom's many competitors, UTC Power has built fuel cells for some supermarkets, a casino and even a high school, but they are expensive. Now the race is on to see who can make them affordable.
A half-dozen big companies have already bought Bloom Boxes at a cost of $700,000 to $800,000. But Sridhar's goal is a $3,000 box that anybody can use to power their home.
"There's always the hope that the price will come all the way down like they did on computers," said University of California Berkeley physicist Richard Muller.
But even the Bloom Box's inventor says home use is 10 years away.
"Don't start signing up for orders yet," said Sridhar. "This is a product of the future."
A future that's at least a decade away.
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