Building Solar Cells Nanowire By Nanowire
The solar cell efficiency limit, known as the “Shockley Queisser Limit” (SQL) has held for many years. But recent research using nanowires seems to show that scientists will soon be able to harvest solar power at much higher levels of efficiency than SQL would dictate.
A Paradigm Shift
In the Journal of Science in January a group of scientists demonstrated that nanowires soak up or concentrate the sun’s rays at unprecedented levels.
In a more recent study in Nature Photonics Journal scientists have been getting better results by improving the quality of nanowires with a cylindrical structure and a diameter about 1/10000 of a human hair. When sun shines on these crystals it is highly concentrated, at up to 15 times higher than normal sunlight resulting in a higher conversion efficiency with each nanowire behaving as if it is gathering light from an area eight times larger than its physical size. These extremely thin nanowires increase the resonance and intensity of light.