New efficiencies in solar photovoltaic cells have been found by a group of international joint teams who combined a layer of silicon with a layer of perovskite material in such a way that both sides generate electricity.
“Third generation” perovskite solar cells are already lower cost and highly efficient. The researchers were able to demonstrate that this “bifacial” solar cell configuration can generate more electricity, particularly in outdoor conditions where the cell can capture reflected and scattered light. The researchers used 14 different materials in the solar cell and had to optimize each one to achieve the best performance. Overall, the new bifacial solar cell has a power conversion efficiency of over 25% and a high power density of 26mW per sq cm.

Although conventional tandem solar cells can also be generate electricity by absorbing additional wavelengths of light, this time the scientists exceeded current performance of tandem configurations.
This new system, which utilizes a traditional silicon base layer and another layer made of perovskite in series, can not only collect more energy, but also capture a lot of light that would otherwise be wasted, reflected and scattered to increase energy output.
Under outdoor conditions, bifacial tandem solar cells achieve efficiencies that exceed those of any commercial silicon solar panel. This is also the first time that bifacial tandem installation has been clearly demonstrated experimentally.
The research was published in Nature Energy.
Reference
Design optimization of bifacial perovskite minimodules for improved efficiency and stability, and Efficient bifacial monolithic perovskite/silicon tandem solar cells via bandgap engineering, Nature Energy
Source
第三代太阳能电池效率显著提升 [Significantly improved efficiency of third-generation solar cells], 环球网[Huanqiu (“World Wide Web”)], 2023-03-24