Innovative conceptual approach in concentrated solar PV/thermal system using Fresnel lens as the concentrator

Photovoltaics (PV) is an ever-evolving field. Significant technological advancement in the PV field has been evident in recent years, including PV concentrators to enhance energy density. The present experimental study explores the viability of using a refractive Fresnel lens for electrical and thermal energy through a novel approach, i.e. irradiance bi-focussing method. Unlike in most of the concentrated PV (CPV) studies, real size PV module (polycrystalline) is used here, and its surface temperature was maintained well within 80°C with the help of a self-sustainable (burlap-based) passive cooling technique. Since the concentrated irradiance gets bifurcated and simultaneously received by both PV module (≈⅓) and the thermal collector (≈⅔), the power output from CPV is more than double compared to the reference module, and the maximum thermal efficiency recorded is 48%. Even the exergy analysis upheld the proposed system as the maximum exergy efficiency is ≈ 2.5 times compared to the reference module. Concerning the heat gain, the thermal collector performance is on par with a conventional solar water heater. Hence, such a combi system can entertain a variety of day-to-day energy applications. Further, as the distance between the concentrator and PV module changes the illumination level, it can be optimized based on the cooling and/or PV module type.