The CIS-based thin-film solar cell (about 0.5cm2) (source: Solar Frontier)
[Click to enlarge image]

Solar Frontier KK (Daiba, Minato-ku, Tokyo) announced Dec 20, 2017, that it has achieved a conversion efficiency of 22.9% with a CIS-based thin-film solar cell in a joint research with New Energy and Industrial Technology Development Organization (NEDO, national research and development agency).

The cell measures about 1cm2. The efficiency of 22.9% is the world's highest conversion efficiency of thin-film solar cell, according to Solar Frontier. The efficiency was confirmed at National Institute of Advanced Industrial Science and Technology (AIST) in November 2017.

The efficiency is 0.3 points higher than the previous world record that the Center for Solar Energy and Hydrogen Research Baden-Wurttemberg (ZSW) of Germany set with a 0.5cm2 cell (22.6%) in February 2016.

Solar Frontier achieved the efficiency record through such technologies as CIS absorber engineering and enhanced surface treatment of the absorber layer.

In February 2017, Solar Frontier announced that it had achieved a conversion efficiency of 19.2% with a CIS-based thin-film solar cell sub-module measuring 30 x 30cm and an efficiency of 19.8% with a mini-module measuring 7 x 5cm. The conversion efficiency of 19.2% is equivalent to 210-220W (per panel). At that time, the company said that the commercialization of high-efficiency (200W per panel) products was coming into sight by applying such results to the production line of Kunitomi Plant in Miyazaki Prefecture.

The latest cell conversion efficiency of 22.9% can realize a solar panel with an output higher than 260W, which is equivalent to the efficiency of crystalline silicon solar panels. The future challenge is to apply the high-efficiency technologies to production lines.