Engineers from Stanford University used basic physics to improve solar panel efficiency. A transparent overlay made of patterned silica releases excess heat and cools down the panels.
Excessive heat affect solar panels efficiency. When heat is radiated away, more photons can be converted into energy.
"Our thermal overlay allows sunlight to pass through, preserving or even enhancing sunlight absorption, but it also cools the cell by radiating the heat out and improving the cell efficiency", said Professor Shanhui Fan who led the research team with doctoral candidate Linxiao Zhu and research associate Aaswath P. Raman. The study debuted in the journal Proceedings of the National Academy of Sciences.
The rise in solar panel use is a big achievement in the quest for alternative energy sources. As more and more people find new ways to use solar panels in their daily lives, excess heat damages its efficiency level. The hotter the panels get, the less energy you get. The discovery of a 'cooling' system is ingenious.
The Stanford team placed a thin layer of patterned silica on traditional solar cells. The transparent layer does not disrupt the visible sunlight that powers up the cells. It acts as a net that captures the heat and radiates the thermal energy away from the solar cells.
The team tested the solar panels with the transparent overlay on Stanford University's rooftop. The findings revealed that the transparent overlay can cool the panels by 22 degrees Fahrenheit or -6 degrees Celsius. The cooling action increases the solar energy by 1 percent. While some think 1 percent is a small feat to ponder, this increase is considered a substantial surge in solar energy production. The team added that the addition of this transparent coating work best in dry environments.
"Our photonic crystal thermal overlay optimizes use of the thermal portions of the electromagnetic spectrum without affecting visible light so you can radiate heat efficiently without affecting color", said Zhu. Cars that make use of this alternative energy source can use the transparent overlay to help 'cool' down the unit and increase performance. A scaled-up version of their prototype will definitely affect the efficiency of solar panels used by large-scale industries.