This sounds like a joke, or a scam perpetrated on gullible greenies, but it’s not.

The technique involves the embedding of square spirals of conducting metal onto a sheet of plastic, each of which, referred to as a “nanoantenna,” just 1/25 the diameter of a human hair. The nanoantennas absorb infrared energy, which is absorbed by the earth during the day and released even hours after the sun goes down. The nanoantennas are thus able to harvest energy both during daytime hours and into the early evening. Because they can take in energy from both sunlight and the earth’s heat, the nanoantennas have a much higher efficiency (and potential applicability) than conventional solar cells.

Like the piezoelectric crowd power or rain power, I just love the idea of harvesting tiny little bits of energy efficiently enough and in sufficient numbers that the sum actually makes a difference.

(TreeHugger and Inhabitat are both great sites, by the way. If you follow those links, look around a bit while you’re there.)