Development of high efficiency and wide acceptance angle holographic solar concentrators for breakthrough photovoltaic applications

Solar concentrator systems represent an important challenge in our society for outstanding photovoltaic (PV) applications. Fresnel lenses or parabolic mirrors concentrate sunlight in a small solar cell surface. On the one hand, Fresnel lenses have an exceedingly small acceptance angle and require expensive tracking systems to follow the path of the Sun. On the other hand, conventional parabolic mirrors need periodic maintenance of the surface reflectivity. Holographic optical elements (HOEs) represent a suitable alternative to Fresnel lenses and solar reflectors, they are cheaper and more versatile. Particularly, multiplexed holographic solar concentrators (HSCs) give an insight into promising possibilities for Building-Integrated Concentrating PV (BICPV). A good trade-off between wide acceptance angle and high diffraction efficiency represents an important milestone in the area. Our research group obtained the higher acceptance angle in a multiplexed HSC design (Morales et. al. Opt. Express 30, 25366 (2022)). This design was composed of seven holographic multiplexed lenses in Biophotopol material with thick thickness, 197 μm. In the present work, more efficient holographic solar concentrators than previous works are shown. As far as we know, it has been obtained the best trade-off between high efficiency and wide acceptance angle HSC-PV solar cell systems. Generalitat Valenciana (CIDEXG/2022/60, IDIFEDER/2021/0.14, PROMETEO/2021/006); Ministerio de Ciencia e Innovación (PID2019-106601RB-I00; PID2021-123124OB-I00); Universidad de Alicante (UAFPU20-23).