Impact of tilt angle, dust deposition, and humidity on potential induced degradation and electrical performance of crystalline silicon photovoltaic modules: an experimental study

Introduction. Photovoltaic (PV) modules constitute the backbone of renewable energy systems, yet their performance is compromised by degradation mechanisms, particularly potential induced degradation (PID), which causes rapid power losses through ionic migration under high voltage stress, creating parasitic shunts that reduce shunt resistance Rsh and energy output. Problem. Although the influence of moisture and temperature has been widely investigated, the combined contribution of operational and environmental factors such as dust soiling remains insufficiently clarified. Goal. This work assesses dust as a contributor to potential induced degradation focusing on the combined effects of tilt angle, dust exposure and dust-moisture interaction on insulation integrity and degradation susceptibility. Methodology. A comparative experimental study was conducted on 3 identical crystalline-silicon PV modules without bypass diodes, installed at tilt angles of 20°, 30° and 40°. A controlled and uniform layer of sandy dust (maximum particle size about 150 μm) was deposited on the front surface. Insulation resistance between the frame and the front glass was measured at three locations (bottom