Bloom Energy has been testing a new device that can generate power on the spot, without being connected to the electric grid, that's inexpensive and clean, with no emissions. It is called the Bloom Box.

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.

Will we have one in every home someday?  Lesley Stahl from 60 Minutes reports.

K.R. Sridhar invited "60 Minutes" correspondent Lesley Stahl for a first look at the innards of the Bloom box that he has been toiling on for nearly a decade.

Looking at one of the boxes, Sridhar told Stahl it could power an average U.S. home.

"The way we make it is in two blocks. This is a European home. The two put together is a U.S. home," he explained.

"'Cause we use twice as much energy, is that what you're saying?" Stahl asked.

"Yeah, and this'll power four Asian homes," he replied.

"So four homes in India, your native country?" Stahl asked.

"Four to six homes in our country," Sridhar replied.

"It sounds awfully dazzling," Stahl remarked.

"It is real. It works," he replied.

He says he knows it works because he originally invented a similar device for NASA. He really is a rocket scientist.

"This invention, working on Mars, would have allowed the NASA administrator to pick up a phone and say, 'Mr. President, we know how to produce oxygen on Mars,'" Sridhar told Stahl.

"So this was going to produce oxygen so people could actually live on Mars?" she asked.

"Absolutely," Sridhar replied.

When NASA scrapped that Mars mission, Sridhar had an idea: he reversed his Mars machine. Instead of it making oxygen, he pumped oxygen in.

He invented a new kind of fuel cell, which is like a very skinny battery that always runs. Sridhar feeds oxygen to it on one side, and fuel on the other. The two combine within the cell to create a chemical reaction that produces electricity. There's no need for burning or combustion, and no need for power lines from an outside source.

In October 2001 he managed to get a meeting with John Doerr from the big Silicon Valley venture capital firm Kleiner Perkins.

"How much do you think, 'I need to come up with the next big thing'?" Stahl asked Doerr.

"Oh, that's my job," he replied. "To find entrepreneurs who are going to change the world and then help them."

Doerr has certainly changed our world: he's the one who discovered and funded Netscape, Amazon and Google. When he listened to Sridhar, the idea seemed just as transformative: efficient, inexpensive, clean energy out of a box.