A programmable compound prism powered by triboelectric nanogenerator for highly efficient solar beam steering

Concentrator photovoltaics (CPV) has great competitiveness in replacing the conventional flat-panel PV system due to its high conversion efficiency and small cell active area. However, the accessory beam steering and concentrating optics are bulky and costly. Here we propose a programmable compound prism (PCP) powered by triboelectric nanogenerator (TENG) for solar beam steering. A disc TENG with a RC circuit could produce DC voltage signal, and the voltage signal could be tuned by varying the resistance in RC circuit. By connecting the variable DC output to the left, right and back walls of the PCP filled with DC 550 silicone oil, DI water and PMX 200 silicone oil, the two oil/water interfaces could be modulated in a programmable manner. A maximum deflection angle range of 15° was achieved in the PCP, which is 38% greater than conventional single prism with only one oil/water interface. The proposed TENG-PCP was employed to deflect an oblique incident laser beam to trigger the power generation in a multi-junction solar cell. With the operation of the proposed TENG-PCP, a 1.2 mW increment was achieved by the multi-junction solar cell, indicating the potential of boosting the CPV by the presented TENG−PCP.