By now you may have seen those little mini solar-powered phone and gadget chargers for sale for about 50 bucks or so, giving you juice whenever and wherever you need it... well, so long as it's not cloudy, and there's no trees or flagpoles in your way, and you've got about an hour to wait for enough of a charge to make a 10-minute call. In other words, the technology is still a little cumbersome, but that's about to change.
The brains at Sandia National Laboratory in Albuquerque have developed some new solar cells that seem just to good to be true -- they're smaller, cheaper and put out more juice than conventional photovoltaics now on the market, but that's not even the cool part. Our favorite characteristic of the glitter-sized cells is that they can bend. And no, that's not a typo, the cells are glitter-sized, or about 20 microns thick - one-fifth the thickness of a human hair - by .25 to 1 millimeter across.
"We've identified more than 20 different effects that come about by making the cells really small," Sandia Research Scientist Greg Nielson tells Daniweb. "The ability to do conformal (or pliable) PV, like putting photovoltaics into a cell phone case."
He says other effects include more efficient energy production and the ability to continue producing electricity without 100 percent direct sunlight. One of the shortcomings in those chargers now on the market is that they require an absolute direct path between the sun and its panels, unobstructed by even the most fleeting shadow. A chain of Sandia's tiny solar cells will be able to keep making power when some of the cells are shaded. That's great news for portable applications like cell phones, laptops or cars, because it means that as long as sunlight is available, the PV cells will continue soaking up rays and converting them to juice without having to constantly worry about orientation towards the sun.
Of course, we don't often leave our smartphones and laptops just lying out in the sun, they're often stowed in pockets or backpacks. But that's no problem either with the new more flexible tiny cells, because they could conceivably be applied to clothing, backpacks, tents or just about any other material that we do put in the path of sunlight as we travel around. Imagine, one day your solar photovoltaic shirt could come with a pocket that doubles as a charging station.
Nielson says there's been significant interest from both tech companies and the government in the technology, and he anticipates we can expect to see it first available for "portable outdoor use" like on cell phones, tents and cars. He also says he expects it to be competitive in the market in a mass production situation, because the smaller cells mean lower material costs.
Image by Murat Okandan, courtesy Sandia Labs.