Some Factors Affecting Power Generation of Solar Panels

Perhaps one day in the use of our photovoltaic system, we will suddenly find that the photovoltaic modules are not producing as much electricity as before. Why is that? Here are three possible reasons for this.

1. The hot spot effect

During outdoor use, components will inevitably encounter fallen leaves, ash, and other obstructions. Under certain conditions, a series of solar cells may become obstructed, reducing their exposure to sunlight and resulting in lower current generation compared to other normal power generation cell. When the working current in a component exceeds the short-circuit current of an obstructed cell, it acts as a load and consumes energy generated by other cells internally. Just like in our daily life, the mobile phone will get hot when charging, and the same is true for this blocked cell. It has been consuming power, and it is inevitable that a large amount of heat will be generated, causing the temperature of this cell to rise. At the same time, some cells in the solar module have defects themselves, such as: cell cracks, broken grids, and virtual welding (the welding strip on the cell fails to be welded to the main grid of the cell), which may also cause the defective cell to rise in temperature during operation. From the thermal imaging of the entire solar panel, you can see that some parts are very bright in color.

This is how the hot spot effect is generated. The hot spot effect not only reduces the power generation effect, but also affects the life of photovoltaic modules. And excessive heat could even lead to fire hazards.

2. Hidden cracks in the battery cell

There are tiny cracks on the surface or inside the battery cell, and these cracks may not be visible to the naked eye.

However, when a cell has a crack, the power generation efficiency of the cell itself will be reduced, and may even affect the entire string of components. Additionally, electrons in the area of the hidden crack may encounter impediments to smooth flow, leading to an escalation in local resistance and subsequent temperature elevation in that region, resulting in a hot spot effect and further damage. Therefore, whether during production and processing or transportation and installation processes, it is crucial to prioritize component protection.

2. The inherent loss of PV module structure

Solar power generation involves the conversion of light energy into electricity, with the solar cell serving as a key component. However, due to its fragility, conventional solar panels utilize tempered glass and film to provide a protective shield for the cells, albeit at the cost of some light interception. Therefore, efforts are being made to enhance light absorption rates. 

For example, MOREGO Solar Panel 225W uses BC cells and places metal grids on the back to increase the absorption rate of light, thereby improving power generation efficiency.