A thermal performance-enhancing strategy of photovoltaic thermal systems by applying surface area partially covered by solar cells

In this work, a single unit called photovoltaic thermal with solar thermal collector enhancer has been developed, whose absorber plate is partially covered by photovoltaic cells. This design increases the photothermal energy conversion ratio and absorbed energy by the system, resulting in a higher thermal power, thermal exergy, and outflow temperature compared to a conventional photovoltaic thermal module. This research examines the impacts of different glazing arrangements on the system performance using a three-dimensional transient model to determine the most efficient design from energy and exergy viewpoints. Moreover, the effects of various parameters on system performance, such as tilt angle, azimuth angle, mass flow rate, and dust accumulation on the system surface, are discussed. Finally, a comparative study between the proposed system, the standalone solar thermal collector, and the standalone photovoltaic thermal system is carried out in terms of energy, exergy, and economics. Results indicate that the proposed system has 31.24 % greater overall power and 35.07 % shorter payback time than a conventional standalone unglazed photovoltaic thermal system when only its solar collector enhancer part is covered by glass.