Experimental study of dust accumulation of photovoltaic modules under different wind directions and its effect on power output characteristics

Dust accumulation is one of the key factors limiting the power generation efficiency of photovoltaic modules. Current research has primarily focused on upwind deposition, while systematic understanding of dust deposition under crosswind and leeward conditions remains lacking. To address this research gap, this study employs controlled indoor experiments to systematically investigate dust deposition characteristics and their impact on module power generation performance under three wind directions (upwind, crosswind, and leeward), four wind speeds (1.3–5.2 m/s), and three tilt angles (30°, 45°, and 60°). Results indicate that localized accumulation causes significantly greater power degradation than uniform distribution. Under crosswind conditions at 2.6 m/s wind speed and 30° tilt angle, dust deposition density reached 1.35 g/m 2 , corresponding to a power loss of 144.6 mW—comparable to the loss (145.6 mW) observed under upwind conditions at 2.6 m/s wind speed and 45° tilt angle. Wind speed exhibits significant directional dependence on deposition behavior: Under upwind conditions, deposition density at a 30° tilt angle first increases then decreases with wind speed, peaking at 3.642 g/m 2 at 3.9 m/s with a maximum power loss of 231.9 mW. Under crosswind conditions, dust deposition continuously increases: at a 45° tilt angle, deposition density rises from 0.965 g/m 2 to 1.735 g/m 2 , with power loss increasing from 78.9 mW to 149.2 mW. Under leeward conditions, deposition decreases significantly with increasing wind speed, reaching a minimum of only 0.136 g/m 2 at a tilt angle of 60°, with power loss as low as 9 mW. Notably, under identical operating conditions, deposition density and power loss under upwind conditions are significantly higher than under crosswind and leeward conditions. Furthermore, increasing the module tilt angle generally reduces dust accumulation and power loss across all wind directions. This study provides crucial theoretical foundations for optimizing photovoltaic array layout, predicting deposition, and implementing cleaning maintenance in dusty environments.