As the push for renewable energy intensifies, scientists are exploring new ways to harness solar power more efficiently. One of the most promising innovations is luminescent solar concentrators, which can transform glass into energy-harvesting surfaces for buildings.
Luminescent solar concentrators (LSCs) use thin, transparent waveguides embedded with luminophores—special molecules or nanoparticles that absorb sunlight and re-emit it at longer wavelengths. This light is confined within the waveguide through total internal reflection, then directed to the edges where solar cells convert it into electricity. The technology can be integrated into windows, building facades, and other glass-heavy structures, making it ideal for urban environments.
Wilfried van Sark, a professor at Utrecht University’s Copernicus Institute of Sustainable Development, explained that LSCs can capture ultraviolet and infrared light while maintaining transparency, crucial for their use in architectural applications. However, challenges remain in identifying the most efficient luminophores and optimizing the design for practical use.
Van Sark and his colleague, Thomas de Bruin, tested 92 luminophores to determine the most efficient setup for converting sunlight into energy. Their research revealed that copper indium sulfide/zinc sulfide core-shell nanoparticles provided the best performance, efficiently capturing sunlight across a wide range of wavelengths.
Despite these advances, LSCs still have lower efficiency compared to traditional solar panels, with a maximum conversion efficiency of about 1% compared to over 20% for conventional systems. However, van Sark sees potential in their application for large-scale surfaces like skyscrapers. “While the efficiency is lower, the vast area available on high-rise buildings makes LSCs a viable option, especially as future buildings aim to be energy-positive,” he said.
Future advancements in material design and waveguide technology may increase efficiency to around 10%, making luminescent solar concentrators a more competitive energy solution in the coming years.
Related topics: