EFFECTS OF SHADING ON THE POWER DELIVERY OF SOLAR PANELS

Solar photovoltaic (PV) technology is a critical low-carbon solution, but its performance is severely compromised by shading. This study addresses the persistent problem of partial shading, which causes disproportionate power losses and creates thermal stress risks like hot spots.This research aims to quantify the effect of shading on PV panel voltage, current, and power output under controlled laboratory conditions.The methodology employed an experimental approach using an SES TPS-3720 Solar Energy Trainer. Experiments measured performance under 0% (baseline), 50% (partial), and 100% (full) shading.The study also evaluated the impact of shading material optical properties by testing opaque (wood), semi-opaque (paper), and translucent (plastic film) materials. Measurements were recorded across five irradiance levels using both LED lamp and DC motor loads.Key findings demonstrate a highly non-linear performance degradation. Partial shading covering 50% of the panel area resulted in a 65-70% power loss, far exceeding a proportional reduction. Full shading with opaque (wood) or semi-opaque (paper) materials caused a 100% power loss, eliminating all usable current. Translucent plastic film caused the least degradation (approx. 23% power loss).The results confirm that a material's optical transmittance, not its physical density, is the dominant factor determining shading severity.These findings validate established photovoltaic theory and highlight the critical importance of shadow avoidance in system design. The study reinforces the necessity of mitigation strategies such as bypass diodes and module-level power electronics (MLPE) in shade-prone installations.