South Korea-based solar cell and module manufacturer Qcells has announced achieving a 28.6% tandem solar cell efficiency on a full-area M10-sized cell that can be scaled for mass manufacturing.

The CalLab at the Fraunhofer Institute for Solar Energy Systems (ISE) verified the company’s claims.

Qcells’ new tandem solar cell technology comprises a perovskite layer on the top and the company’s proprietary Q.ANTUM technology layer on the bottom. The solar top layer is designed to capture high-energy light, and the bottom layer captures the lower-energy light passing through.

The value is a total-area measurement on a full-area M10-sized (roughly .36 square feet or 330.56 cm²) cell produced on Qcells’ R&D pilot line in Germany using a standard industrial silicon wafer that can be interconnected into an industrial module.

This design aims to improve ‘power per area’ to generate the same energy as conventional solar systems using fewer solar panels.

This approach to tandem development focuses on commercial processes and tools that readily scale to mass manufacturing rather than attempting to show proof of concept in a lab-scale environment.

Qcells began developing the large-area tandem technology in 2023. It said the breakthrough has the potential to further reduce the cost of solar energy and the land footprint needed for solar projects, making solar even more affordable, accessible, and sustainable.

In September, researchers from the Huazhong University of Science and Technology in China claimed to have developed an all-perovskite tandem solar cell with a record power conversion efficiency of 28.49%.

Earlier this year, researchers at the National University of Singapore announced a  27.1% energy conversion efficiency from a novel triple-junction tandem solar cell.

In June this year, researchers at Fraunhofer ISE developed a Tunnel Oxide Passivated Contact solar cell in the large-area M10 silicon wafer format, achieving an efficiency of 24%.