Electrical and optical characterizations and modeling of bifacial photovoltaic mini-modules integrated into solar air heaters

Abstract

Solar energy is a sustainable substitute for fossil fuels that have an undesirable environmental impact in addition to the danger of depletion. Despite their potential, conventional solar air heaters (SAHs) are limited to thermal applications and suffer low efficiency due to heat loss and design constraints. Photovoltaic-thermal (PVT) systems, which simultaneously generate electricity and heat, offer a promising alternative. This study investigates the integration of bifacial photovoltaic (PV) minimodules into SAHs, with the aim of enhancing their performance and expanding their functionality. The objective of this work is to compare the optical and electrical performance of SAHs integrated with a bifacial PV mini-module in comparison to conventional SAHs with glass only. The methodology adopted is based on experimental optical and electrical characterizations in different wavelength ranges. The results reveal that 80.79% of the incoming irradiance reaches the absorber plate in conventional SAHs with glass only, while the rest is lost due to reflection and absorption. However, in SAHs with PV mini-module, 26.09% of the irradiance reaches the absorber plate, 54.53% of the total energy is absorbed in the PV cell contributing to electricity (10.53% is harnessed as electricity in the 300–1200 nm wavelength range) and heating (44.00%) generation, 10.11% of the total energy is absorbed in the surroundings of the PV cell, and the remaining 9.27% is lost due to reflection. These findings shed light on the intricate energy distribution and utilization within PV mini-modules when integrated into SAHs. More importantly, this study establishes a foundation for the design and optimization of efficient PVT-SAH systems in future research and development efforts.