I’ve done a couple of different keyword searches and found no mention of this onsite. Sorry if it has already been covered.
While photovoltaic panels hold great potential for supplying clean power, that potential is only realized when sunlight hits the cells directly. Solar installations often use tracking motors to move the panels as close to perpendicular to the sun as possible. Being more complex than just panels on a roof, those systems are consequently more subject to breakdowns.
Stanford University’s Nina Vaidya and Olav Solgaard set out to solve the “tracking” problem with no moving parts and, serendipitously, solved a second solar challenge: clouds.
Using lenses with layers of decreasing size the researchers were able to increase the effectiveness of solar cells under angled light and the diffused light of a cloudy day.
Their Axially Graded Index Lens, or AGILE, uses diffraction to concentrate light, not unlike the Fresnel lens of a lighthouse lamp. While the graded lenses do reduce direct, perpendicular light by 10%, they increase angled and diffuse light sufficiently to triple the effectiveness of solar cells.
The AGILE concept is a revolution in photovoltaics that will lead to smaller, cheaper and vastly more efficient installations at every scale while reducing the industry’s ecological footprint.
Watch this space.
Stanford press release