The Fraunhofer Institute for Solar Energy Systems ISE claims to have achieved 68.9% conversion efficiency of IIIV solar cells that can be used in laser power transmission systems.
“In this new form of energy transfer, called optical power, the laser energy is sent to the photovoltaic cell through the air or optical fiber, and its characteristics match the power and wavelength of the monochromatic laser,” the scientists said. explained. “Compared with traditional copper cable power transmission, light power systems are especially suitable for applications that require electrically isolated power supplies, lightning protection or explosion protection, electromagnetic compatibility or complete wireless power transmission. For example.” The
laser energy transmission system is not much different from the energy transmission system based on microwave technology. These systems convert energy into a transmitter, which produces directional electromagnetic radiation, which is then absorbed by the receiver. The latter can convert this energy into electricity, heat or hydrogen. These systems can be used to monitor wind turbines and high voltage lines, as well as fuel sensors in aircraft fuel tanks and passive optical networks. The
battery is built from a layer that grows on a gallium arsenide substrate, then is removed and then a high reflection mirror is applied to the back of the remaining ultrathin semiconductor structure. The reflector is optically optimized using a combination of ceramic and silver, and the cell absorber is based on nitrogen-doped gallium arsenide and p-type aluminum gallium arsenide.
“This thin film method has two obvious advantages in terms of efficiency,” explains Henning Helmers, director of the Fraunhofer ISE research team. “First, the photons are trapped in the battery and the absorption of photon energy near the band gap is maximized, while at the same time, heating and transmission losses are minimized, making the battery more efficient. Second, the additional photons generated internally through radiation recombination are efficiently captured and recovered. This prolongs the effective life of the carrier, thus further increasing the tension.
Other Fraunhofer ISE researchers achieved a 35.9% conversion efficiency of silicon-based monolithic triple junction IIIV solar cells in April. In August 2020, the institute announced that it would grow directly on silicon. The conversion efficiency of tandem solar system IIIV cell is 25.9%. The cell is an improved version of the IIIV solar cell with an efficiency of 34.5%. The cell is manufactured by a process called direct wafer bonding, in which the IIIV layer is first deposited on gallium aluminum arsenide (GaAs)
Researchers at the University of Tampere in Finland recently developed a multiple junction solar cell IIIV, which is said to have the potential to reach an energy conversion efficiency close to 50%. The National Renewable Energy Laboratory (NREL) announced last year that the efficiency of tandem battery kits using IIIV materials was 32.9.