In the world of energy, the Holy Grail is a power source that's inexpensive and clean, with no emissions. Well over 100 start-ups in Silicon Valley are working on it, and one of them, Bloom Energy, is about to make public its invention: a little power plant-in-a-box they want to put literally in your backyard.You'll generate your own electricity with the box and it'll be wireless. The idea is to one day replace the big power plants and transmission line grid, the way the laptop moved in on the desktop and cell phones supplanted landlines.Two boxes can power the average high-consumption home and one box can power the average low-consumption home, at least that's the claim being made by K.R. Sridhar, founder of Bloom Energy, on the 60 Minutes show on CBS. The original technology comes from an oxygen generator meant for a scrapped NASA Mars program that has been converted, with the help of an estimated $400 million in private funding, into a fuel cell.Bloom's design feeds oxygen into one side of a cell while fuel (natural gas, bio gas from landfill waste, solar, etc) is supplied to the other side to provide the chemical reaction required for power. The cells themselves are inexpensive ceramic disks painted with a secret green "ink" on one side and a black "ink" on the other. The disks are separated by a cheap metal alloy, instead of more precious metals like platinum, and stacked into a cube of varying capabilities - a stack of 64 can power a small business like Starbucks.Now get this, skeptics: there are already several corporate customers using refrigerator-sized Bloom Boxes. The corporate-sized cells cost $700,000 to $800,000 and are installed at 20 customers you've already heard of including FedEx and Wal-mart - Google was first to join this green energy party, using its Bloom Boxes to power a data center for the last 18 months. Ebay has installed its boxes on the front lawn of its San Jose location. It estimates to receive almost 15% of its energy needs from Bloom, saving about $100,000 since installing its five boxes 9 months ago - an estimate we assume doesn't factor in the millions Ebay paid for the boxes themselves. Bloom makes about one box a day at the moment and believes that within 5 to 10 years it can drive down the cost to about $3,000 to make it suitable for home use, which sounds awfully expensive. Nevertheless, Bloom Energy will go public with details on the 24th of February.Via: Engadget