Optical design and efficiency improvement for organic luminescent solar concentrators

Organic luminescent solar concentrators (LSCs) have been widely investigated due to their potential in dramatically decreasing the cost of collecting solar energy. We designed, fabricated organic LSCs at different sizes and characterized their optical and electrical properties. The output efficiency enhancement methods for LSCs photovoltaics (PVs) are explored including attaching white diffusers on the bottom surfaces of LSCs, and adding a refractive index matched optical gel between the LSC edge surfaces and the attached PV cells. To further improve the output power conversion efficiency, multi-layered LSCs are studied and compared with single layered LSCs. The distribution of the output current from the LSC edges varies slightly, which is beneficial to collection of the concentrated light by attached PV cells. Also, in comparison with applying a wavelength selective film, the alignment of dye molecules using polymerized liquid crystal is discussed as a promising optical design and efficiency improvement method.