Comparing the Indoor and Solar Performance of Light‐Concentrating Waveguide‐Encoded Lattice Slim Films

ABSTRACT Although multicrystalline Si photovoltaics have been extensively studied and applied in the collection of solar energy, the same systems suffer significant efficiency losses in indoor settings, where ambient light conditions are considerably smaller in intensity and possess greater components of non‐normal incidence. Yet, indoor light‐driven, stand‐alone devices can offer sustainable advances in next‐generation technologies such as the Internet of Things. Here, we present a non‐invasive solution to aid in photovoltaic indoor light collection—radially distributed waveguide‐encoded lattice (RDWEL) slim films (thickness 1.5 mm). Embedded with a monotonical radial array of cylindrical waveguides (±20°), the RDWEL demonstrates seamless light collection (FoV (fields of view) = 74.5°) and imparts enhancements in J SC (short circuit current density) of 44% and 14% for indoor and outdoor lighting conditions, respectively, when coupled to a photovoltaic device and compared to an unstructured but otherwise identical slim film coating.