Theoretically solar cells can harvest about 33.5 percent of energy from sunlight. But practically no current solar technologies have ever reached close to this high efficiency rate. Indeed, there is a huge gap between the amount of power the existing solar cells reap and what can be really achieved. How to abridge the gap? A team of researchers at the University of California, Berkeley has coined up a counter-intuitive concept that can provide an efficiency of a whopping 26 percent.
The solar researchers under Eli Yablonovitch, electrical engineer professor at the UC Berkeley, have conceived the idea of designing solar cells to be more like LEDs. The shining solar cells can absorb more photons and thus provide more energy efficiency, the researchers claim. In fact, what the researchers have demoed is that the better solar panels at emitting photons, the higher the energy they can generate, explains Yablonovitch.
Years back, solar scientists found that solar cells can really have a maximum efficiency rate of around 33.5 percent. That means 33.5 percent of power from sunlight can be turned to electricity. However, most of current solar panel technologies fall far short of the maximum efficiency rate achievable. It is here the Berkeley researchers wanted to find out a method that can reduce the gap between the theoretical and practical limits.
Based on the study results Alta Devices, a PV manufacturing firm co-founded by Yablonovitch, has developed prototype of the LED-like solar cell from gallium arsenide (GaAs). The illuminating solar panel has broken all efficiency records with its 26 percent rate. Yablonovitch promises that more advances in technology will take it to 30 percent in coming years. The researchers will demonstrate the technology at the Conference on Lasers and Electro-Optics in San Jose, Calif.