EU’s CitySolar project advances clear solar window technology

The EU-backed CitySolar project developed transparent solar cells using perovskite and organic layers to absorb infrared and ultraviolet light while allowing visible light to pass through. Researchers under the project built solar glass with 30% transparency and achieved a record 12.3% efficiency using layered cell technology. These cells can be integrated into building windows without affecting visibility or aesthetics, enabling solar generation in urban environments. The Italian National Research Council will lead the project, which included nine partners from seven different countries. The team included the University of Southern Denmark, Friedrich-Alexander University, the University of Rome Tor Vergata and a research center in France. The team worked on real-world uses but faced problems with cost, design, and how well the solar cell worked. Scaled deployment on urban glass surfaces could expand solar output without relying on ground-mounted installations.