Researchers at the King Abdullah University of Science and Technology (KAUST) Photovoltaics Laboratory (KPV-Lab) of the KAUST Solar Center, a leading institute of research excellence in the Kingdom of Saudi Arabia, claimed on 13 April that it has produced a perovskite-silicon tandem solar cell with a power conversion efficiency of 33.2%, which was confirmed by the European Solar Test Installation (ESTI) as the top of the National Renewable Energy Laboratory’s (NREL) Best Research-cell Efficiency List.

The team has been working on the perovskite-silicon tandem cell concept since 2016, including related methods, equipment, new materials to code with many issues involving uniformly covering the micrometre-sized pyramidal surface of silicon cells with perovskite material and so on. This led to the creation of the tandem solar cell, which combines perovskite top cells with an industrially compatible, double-sided textured silicon bottom cell that maximises the capture and conversion of sunlight into electricity more efficiently than the conventional single-junction silicon analogues, as the perovskite top layer absorbs blue light best, while the silicon base absorbs red light best, achieving a higher conversion efficiency than the Helmholtz-Zentrum Berlin (HZB) record of 32.5%.

“The new record is the highest power conversion efficiency of any dual-junction solar cell under non-concentrated light, and demonstrates the tremendous promise of perovskite-silicon tandems to deliver ultra-high performance photovoltaic modules, which is critical to rapidly achieving renewable energy goals to combat climate change,” said Dr Stefaan De Wolf, Professor of Material Science and Engineering and Interim Associate Director of the KAUST Solar Center.