Alta Achieves 31.6 percent Solar Energy Efficiency Record
According to testing by NREL the USA's National Renewable Energy Laboratory, Alta Device's new dual-junction solar cell is the world's most efficient 1-sun cell at 31.6 percent efficiency. This is the seventh overall solar efficiency record that Alta Device has set since 2010.
Alta has achieved this latest record by modifying its basic single-junction GaAs material. The company's dual junction technology builds on the basic GaAs approach, but implements a second junction (or layer) with InGaP.
Because InGaP uses high-energy photons more efficiently, the new dual-junction cell generates more electricity from the same amount of light.
Alta believes its technology now redefines how solar technology can be used, in particular, for the UAV (unmanned aerial vehicle) market due to the increased power-to-weight ratio.
"Our goal has always been to enable solar power to be useful in configurations and applications that have never before been possible," said Rich Kapusta, Alta Devices chief marketing officer. "The UAV application is an important example of how this happens."
As an example, on a typical HALE (high altitude long endurance) UAV aircraft, Alta's solar material requires less than half of the surface area and weighs one-fourth as much while providing the same amount of power as competing thin film technologies.
These savings open UAV designers to a variety of alternative design options, according to Alta. Additional batteries can be installed on the vehicle, providing longer operational life spans and flight times than originally considered. Alternatively, payload functionality can be tailored for higher speed or longer distance wireless communications.