University of Utah researches have developed a thin glass film that could boost the overall efficiency of solar cells to more than 50%. To achieve the increase in efficiency researches at the U have created a film that is five times thinner than a human hair. It can separate the broad-spectrum rays of sunlight into individual colors, sort of like a prism.
Current solar cells usually only absorb the energy of light from very narrow wavelengths, which means the rest of the energy from the other wavelengths is wasted as heat. This problem puts a theoretical limit on how efficient a solar cell can be, but the new film essentially gets around that limitation by directing specific wavelengths to materials in the cell that are best suited to capture them. University of Utah Electrical engineering professor Rajesh Menon says increasing solar cell efficiency will be key to decreasing energy costs in the future.
“In other words, for the same cost you are now producing more energy," he says. "So, if you think along those lines the impact of efficiency on the cost of solar power can be quite significant. It can have almost a multiplicative effect.”
Menon says the next step in the process is to work with materials researchers to create the right kind of solar cell that can best take advantage of their film and after that,
“I’m extremely terrible at predicting the future, but I would guess in five to 10 years it is possible to come up with a working commercial prototype system,” he says.
The technology also has several other potential applications, including generating brighter, more power-efficient LCD displays, and better low light performance for digital cameras.