The Stuggart-based scientists achieved this record by defeating Japanese-made cell with 0.3%. The Fraunhofer Institute for Solar Energy Systems ISE has confirmed the results.
The present development is testament of the fact that thin-film solar PVs based on copper iridium gallium diselenide has increased in efficiency in the past three years than it has been in the past 15 years.
With increase in efficiency, the cost of the solar PV manufacture comes down and makes it more and more affordable for deployment.
The new thin-film solar PV was manufactured at the laboratory’s coating plant using co-evaporation method.
The thin-film has an area of about 0.5cm2, which is a standard size for test cells. But, the efficiency rate could be increased by improving the manufacturing process at several points. These include post-deposition of CIGS surface with alkaline metal compounds being added into this layer.
The momentum to improve thin-film solar panel efficiency between 1998 and 2013 was very less with about 0.1% improvement per year. But from 2013, the rate of percentage improvement has gone up from 0.1% to 0.7% per year.
With these achievements, the institute is confident that thin-film solar PVs will become a good contender for silicon-based solar PVs which has been dominating the solar market until now.
But, the researchers at the institute believe that there is still plenty of untapped potential in the technology behind CIGS solar cells.
ZSW board member and Head of the Photovoltaics division, Prof. Michael Powalla said:"I expect that we can achieve up to 25 percent efficiency in the years ahead."
ZSW has plans to introduce the new advancement from laboratory to factory with its industry partner Manz. Manz is a Reutlingen-based engineering firm offering turnkey manufacturing lines for CIGS thin-film solar modules.
