The factors that affect the power generation of photovoltaic modules
Hengyuantai introduces the factors that affect the power generation of photovoltaic (PV) modules.
Module Quality: Factors such as microcracks in the cells, poor-quality materials, oxidation, hot spots, cold solder joints, and defects in the backsheet can affect the module’s power output during long-term operation, thus impacting power generation.
Solar Radiation Intensity: Given a constant conversion efficiency of the solar cells, the power generation of a photovoltaic system is determined by the intensity of solar radiation. The power output of a PV power station is directly related to the amount of solar radiation.
Environmental Humidity: Since photovoltaic systems operate outdoors for extended periods, excessive humidity can lead to water vapor penetrating through the backsheet and into the module. This causes the EVA (ethylene-vinyl acetate) to degrade, and acetic acid ions can leach metal ions from the glass. This results in high bias voltage between the internal circuits and the frame, leading to a reduction in electrical performance and decreased power generation.
Ambient Temperature: Changes in external temperature and the heat generated during module operation can increase the temperature of the module, which in turn can cause a decrease in the module’s power output.
Installation Tilt Angle: Even at the same geographic location, different tilt angles of the modules can result in varying amounts of solar energy absorbed, leading to differences in power generation.
Shading and Obstruction: Shaded areas of the module will not contribute to power generation and may become energy-consuming loads within the module. Additionally, shading can cause localized heating, which may lead to EVA aging and yellowing. This decreases the transparency of the affected area, impacting overall power generation.