A new concentrating photovoltaic (CPV) device developed by Germany’s Fraunhofer ISE has pushed the efficiency of solar power further than before, reaching 41.4 percent efficiency. That’s the highest rate of conversion efficiency for a solar device to date.
In tests Fraunhofer and partners, including Soitec have created devices that have converted more of the sun’s power into electricity—converting 46 percent of the sun’s energy into electricity, but in test conditions. The new device developed by Fraunhofer, with support from the EU’s CPVMatch, project uses special optics to concentrate the sun on multi-junction solar cells, allowing them to convert more of the sun’s light into electricity across a 122 cm square device.
“In CPVMatch, we have addressed all production steps for concentrator modules starting from the materials, through cell fabrication and production systems, and up to the challenges facing module manufacturing,” said Dr. Gerald Siefer, project head and group leader of III-V Cell and Module Characterization at Fraunhofer ISE.
Silicon solar panels continue to dominate installations across the world. But high-concentration photovoltaic (HCPV) devices, such as this one, could be used in certain circumstances, particularly those with high direct normal irradiance.
“We are extremely pleased about these results that pave the way for further efficiency increases in the concentrator technology,” says Dr. Andreas Bett, institute director of Fraunhofer ISE. “Photovoltaics is booming worldwide, and we see great potential for this particularly efficient module technology. It significantly decreases the use of resources for energy conversion per unit area and thus contributes to more sustainability.”
The HCPV devices, which use PV cells with three or more junctions, absorb light from different spectra of the sun. By sandwiching the layers into one device it maximizes the amount energy that can be harvested in a minimum amount of space, using a minimum amount of materials. When coupled with optical concentrators they’re able to harness even more of the sun’s light. To increase their ability to harness even more of the sun’s light, the modules are mounted on a two-axis tracking system, following the sun as it moves across the sky.
The research institute said that in developing the new HCPV concentrator over the past 3.5 years, it achieved two important results. First, it created multi-junction solar cells with new materials and manufacturing processes. Second it improved optics for the HCPV device through modifying the optics by making use of achromatic lenses.Tweet