The Effect of Solid Dirt on the Output Performance of Solar Module

Accumulation of solid dirt on solar module surfaces significantly reduces output performance. This study investigated the effects of solid dirt accumulation (mixture of algae, sand, dust, and moist air) on two 250W monocrystalline solar modules—one clean (control) and one soiled (device under test). Measurements of open circuit voltage, short circuit current, I-V characteristics, and soiling losses were taken at 15-minute intervals over multiple days. Results showed power output losses ranging from 26% to 42%, with an average daily loss of 34.0% ± 8.0%. The dirty module generated 1286.813W compared to the control module's 1758.487W on one test day, and 2051.732W versus 3539.326W on another. The study demonstrates that solid dirt reflects incident solar radiation, reducing both output voltage and power compared to clean panels, highlighting the importance of regular cleaning for optimum solar panel efficiency.