'3D solar' panel works underground

A research team at Georgia Tech makes a game-changing breakthrough for the solar industry -- fiber optic solar cells that can work indoors (or even underground).

Fri, Nov 20 2009 at 8:33 PM EST

Photo: Georgia Tech

November has been a breakthrough month for the solar industry. On the heels of an announcement by an Australian research team that broke the 43 percent efficiency barrier in solar PV technology, another team at the Georgia Institute of Technology headed by Dr. Zhong Wang pioneered a new kind of solar cell that uses fiber optics to generate electricity.

This is one of the biggest breakthroughs in the industry, promising an eventual "liberation" from the traditional solar panel and the potential to produce electricity without having to max out your south-facing roofs with heavy and expensive rigid solar cells.

The researchers call it "3D" solar because protons are allowed to move in multiple directions via a bundle of transparent fiber optic cables coated with zinc oxide. The tips of the cable bundle would be exposed to direct sunlight, and as the photons collected moved through the cables, they generate electricity. Then each photon bounces back, allowing the cable to collect additional energy missed in the first pass.

The polymer cables are tiny (just slightly thicker than human hair) but they provide a low-cost method of producing electricity on demand. A single 10 centimeter cable can produce 0.5 volts, and a 10 watt light bulb could be powered by a 10-cm long bundle (equivalent to handful of human hair — 10,000 cables).

What the cables lack in efficiency (3-8 percent) they make up for in ease of production, low temperatures and no silicon. And because the cables are protected from outdoor weather, they could be made from cheap plastic. A great use, in my book, for petroleum.

via: ABC Australia