Knowledges

Why TOPCon Technology Excels in Low Irradiance Performance

The low irradiance performance of photovoltaic modules is directly related to the energy generation efficiency and stability of solar power systems, significantly impacting their power output capabilities. TOPCon technology demonstrates superior low irradiance performance compared to XBC, largely due to their structural characteristics.

Optimized Leakage Current Path Distribution: TOPCon solar cells feature a tunneling oxide layer formed on their surface, which effectively reduces leakage current paths. These paths are primarily located around the perimeter of the cell rather than in the grid line areas, significantly minimizing leakage routes and effectively controlling leakage current. In contrast, cells utilizing other technologies often have a higher number of grid lines on the back electrodes, which increases the leakage pathways. This exacerbates leakage issues under low irradiance conditions, making TOPCon a more effective performer in this aspect.

Good Parallel Resistance Characteristics: The parallel resistance (Rsh) of a solar cell is closely linked to its low irradiance performance; a higher Rsh indicates better performance under these conditions. The structural design of TOPCon allows for relatively larger parallel resistance, reducing current losses even in low irradiance scenarios and maintaining robust energy generation capabilities. For instance, during reverse bias voltage testing, the leakage current of TOPCon cells is significantly lower than that of several other structural types, laying a solid foundation for their impressive performance under low light conditions.

Reduced Front Grid Line Shading: TOPCon cells utilize a bifacial contact structure, which aids in minimizing shading caused by front grid lines, thereby enhancing the cell's light absorption efficiency. In low irradiance environments, even with weaker light intensity, these cells can absorb as much light as possible and convert it into electrical energy, thereby boosting their power generation capabilities.

Better Rear Heat Dissipation: Compared to certain complex back structures found in other solar technologies, TOPCon cells have a simpler rear structure that allows for more efficient heat dissipation. Under low irradiance conditions, the operating temperature of the cells can affect performance. Superior heat dissipation ensures that TOPCon cells can operate stably even in low light, reducing performance degradation due to elevated temperatures.

Passivation Layer Reduces Carrier Recombination Losses: The passivation layer in TOPCon technology effectively minimizes carrier recombination losses. In low irradiance scenarios, the generation of charge carriers is relatively limited; if recombination losses are high, it severely impacts the cell's performance. TOPCon's passivation layer mitigates these losses, maintaining good cell performance even in low-light environments and enhancing the energy conversion efficiency of the cells.

With 15 years of experience in the solar industry, Ooitech offers TOPCon production line equipment and comprehensive training services. For more information on our products, visit our YouTube channel to watch the MBB Full Automatic solar panel production line video and subscribe for the latest updates.