A team of researchers from AVANCIS, a solar module manufacturer in Munich, Germany, has broken the 20% efficiency barrier for CIGS thin-film modules measuring 30 cm x 30 cm. The previous record, also set by AVANCIS, was 19.8%. The new efficiency of 20.3% was independently certified by the National Renewable Energy Lab.

The company’s researchers made essential improvements to the materials used in the solar panels, including optimizing a material called Ga-rich Cu (In, Ga) (S, Se)2 through a special chemical process. They also treated the material with sodium after it was deposited and used a special zinc-based buffer that did not contain cadmium.

The advancements in the manufacturing process can be applied to AVANCIS’ ongoing product series, which means they can make more solar panels with these improvements. The company said these large solar panels give architects much freedom to design solar facades. Its color technology allows the panels to have dynamic colors, creating an interplay of light and color in architectural designs.

In March, Midsummer, a Swedish developer, in collaboration with researchers at the University of California, Los Angeles, developed a four-terminal perovskite-CIGS tandem solar cell that has demonstrated an efficiency of 24.9%. This is the highest efficiency ever achieved for a CIGS solar cell.

The development of more efficient CIGS solar cells is a major step forward for the solar industry. CIGS solar cells are thin, flexible, and lightweight, making them ideal for a variety of applications, including building-integrated photovoltaics (BIPV) and rooftop solar systems. The higher efficiency of these new cells will make them more cost-competitive with other types of solar cells, such as crystalline silicon cells. This could help to accelerate the adoption of solar energy and contribute to a cleaner, more sustainable future.