Physicists at North Carolina State University say they have found a way to increase the energy handling capacity of solar cells, a discovery that could dramatically improve photovoltaic cell function and productivity in solar panels. As reported on the NC State web site, the new technique improves the connections between stacked solar cells, which should improve the overall efficiency of solar energy devices and reduce the cost of solar energy production. The new connections can allow these cells to operate at solar concentrations of 70,000 suns worth of energy without losing much voltage as “wasted energy” or heat.
By inserting a very thin film of gallium arsenide into the connecting junction of stacked cells the physicists say they can virtually eliminate voltage loss without blocking solar energy, according to Dr. Salah Bedair, a professor of electrical engineering at NC State.
Photovoltaic energy companies are interested in using lenses to concentrate solar energy, from one sun (no lens used) to 4,000 suns or more. But if the solar energy is intensified to 700 suns or more the connecting junctions used in existing stacked cells begin losing voltage. And the more intense the solar energy, the more voltage those junctions lose, thereby reducing the conversion efficiency.