Today's solar cells have two major barriers. They only absorb about 67% of sunlight and can only work at specific angles. But now, researchers at the Rensselaer Polytechnic Institute have made breakthroughs on both problems with a new antireflective coating that increases that number to a stunning 96%.

"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, the professor of physics at Rensselaer who led the research project.  "Our new antireflective coating makes this possible." The research is detailed in an article in the journal Optics Letters.

Researchers on the project created a 7-layer cake of 50-100 nanometer coatings that allows the cell to absorb all wavelengths of light from all angles. The team believes their sun sponge could render mechanized solar panels - which follow the sun to maximize energy - simply unnecessary.

I'm not sure how these gains translate into actual solar cell efficiency, but to me this sounds like the kind of technology that could make widespread rooftop PV a reality.