Impact of Environmental Factors on the Performance of Legacy Photovoltaic Modules Along the Mediterranean Coast

Abstract

This study investigates the influence of key environmental parameters, temperature, wind speed, and relative humidity on the performance of two legacy polycrystalline photovoltaic modules, PV(A) (regularly cleaned) and PV(B) (naturally soiled). In the Mediterranean region of Algiers, experimental outdoor surveillance was conducted under simulated circumstances. Results indicate that temperature contributed to a mean relative decrease in output of approximately 1%, representing the average performance reduction associated with temperature variations over the measurement period. In contrast, relative humidity had a more pronounced adverse effect, resulting in a 5.5% loss in output for both PV(A) and PV(B). Although both modules showed a comparable decline in power with increasing humidity, PV(B) consistently produced lower output values, with a minimum recorded power of 65.47 W, mainly due to dust accumulation interacting with climatic conditions. Wind demonstrated a beneficial compensating effect: average wind speeds above 4 m/s increased the energy yield of PV(A) and PV(B) by 2.6% and 2.4%, respectively, through enhanced convective cooling. These findings highlight the complex interactions between environmental factors and PV performance, underscoring the need for appropriate operational strategies, periodic cleaning, and optimised system design to ensure reliable energy harvesting in coastal Mediterranean climates.