Nano coating ensures near perfect absorption of sunlight

November 4th, 2008 - 2:08 pm ICT by IANS  

Washington, Nov 4 (IANS) A nanoengineered reflective coating on silicon solar cell, which otherwise absorbs only two-thirds of the sunlight, boosts it by another third to tap the valuable energy. This huge gain was consistent across the entire spectrum of sunlight, from ultraviolet to visible light and infrared, and moves solar power a significant step forward towards economic viability.

The new antireflective coating developed by Rensselaer Institute researchers thus helps overcome two major hurdles blocking the progress and wider use of solar power.

“To get maximum efficiency when converting solar power into electricity, you want a solar panel that can absorb nearly every single photon of light, regardless of the sun’s position in the sky,” said Shawn-Yu Lin, professor of physics at Rensselaer and a member of the university’s Future Chips Constellation, which lead the project.

An untreated silicon solar cell only absorbs 67.4 percent of sunlight - meaning that a third of that energy is unharvestable. It is a major barrier hampering the proliferation and widespread adoption of solar power.

After a silicon surface was treated with Lin’s new nanoengineered reflective coating, the material absorbed 96.21 percent of sunlight - meaning that only 3.79 percent of the sunlight was unharvested, according to a Rensselaer press release.

This same is true of conventional solar panels, which is why some industrial solar arrays are mechanised to slowly move throughout the day so their panels are perfectly aligned with the sun’s position in the sky.

Without this automated movement, the panels would not be optimally positioned and would therefore absorb less sunlight.

Lin’s discovery could antiquate these automated solar arrays, as his antireflective coating absorbs sunlight evenly and equally from all angles.

Results of the year-long project were published this week by Optics Letters.

Related Stories

Tags: , , , , , , , , ,

Posted in World |