KIER sets a 26.7% record for a perovskite-CIGS tandem solar cell

Here's the efficiency wire. The Korea Institute of Energy Research has put 26.7 per cent on a perovskite-on-CIGS tandem cell, and Germany's Fraunhofer Institute for Solar Energy Systems has certified the number. The U.S. National Laboratory of the Rockies — NLR, the lab that used to answer to NREL — has parked the same result on its Best Research-Cell Efficiencies Chart. EurekAlert carried the National Research Council of Science and Technology release; Solar Now carried the same note around 4–5 September 2026. The prior mark was 26.3 per cent. Korea just moved it.