Coating helps solar panels soak up more sun

By Julie Steenhuysen

CHICAGO (Reuters) - A new type of reflective coating can make solar panels far more efficient, soaking up nearly all available sunlight from nearly any angle, U.S. researchers said on Monday.

Current solar panels -- which convert energy from the sun into electricity -- absorb only about two-thirds of available sunlight.

But surfaces treated with a coating developed at Rensselaer Polytechnic Institute in Troy, New York, can harvest 96.2 percent of sunlight.

"That is a tremendous savings," Rensselaer's Shawn-Yu Lin, whose study appears in the journal Optics Letters, said in a telephone interview.

Lin said the technology addresses two main problems in current solar cells. It captures more colors of solar spectrum and it captures light from all angles.

"If you look at a solar panel, it looks a bit bluish," Lin said. That is "telling you not all of the blue color is being absorbed. It should look totally dark."

The other problem is that solar panels work best when sun shines directly on them. To solve this, large solar arrays mechanically shift position throughout the day -- much like sunbathers on a beach.

Lin and colleagues think they have found a better solution.