Solar at Night? Soon.
Categories: Solar Technology.
“Solar at night” may no longer be an oxymoron.
Most solar panels operate at only 20% efficiency, which means that 80% of sunlight’s punch is still lost. Truly high-end cells might manage to nab 40%, which would be great - for a batting average. But all told, most companies have been willing to accept this, as a sort of solar glass ceiling. And to that end, many of them have worked to make solar panels cheaper, not better.
Scientists suggest they can manage 80%. We have nanotechnology to thank.
The Idaho National Laboratory has coated their panels with small, spiral solar microantennas, each of which is 1/25th the width of a human hair - a thousand atoms thick, which I dare say is pretty tiny. In the image above, you’re looking at a few billion of them - in an area no bigger than a tablecloth. Each square there contains about 260,000,000 of the little buggers. That’s an added convenience of being so tiny - you can place them just about anywhere, including on flexible materials like a plastic sheet.
At this scale, these antennas just about pulse with energy, soaking up even the infrared edge of the spectrum. The thing about infrared radiation, as well, is that it’s available at night, which suddenly gives stargazing a whole new meaning.
Of course, they can’t quite turn this infrared energy into electricity. They can capture it, sure, but the frequency happens to oscillate at about ten billion times a second - about 150 million times faster than most appliances can currently handle. Next step: very, very tiny converters.
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