Recently, there are more and more small partners consulting the issue of photovoltaic power generation. Xiaobian has collected some of the most influential factors of photovoltaic module power generation, hoping to help you!
1. Component quality
Due to factors such as hidden crack, black core, oxidation, virtual welding, material defects such as backplane and long-term aging, the power of the components is affected during long-term operation, resulting in low power generation of the components. It is noteworthy that the crystal structure of single crystal determines its better performance in the resistance to hidden crack.
2. PID effect
In the long-term external work of the component, water vapor penetrates into the component through the backplane, resulting in the hydrolysis of EVA and the precipitation of metal ions in the glass caused by acetic ion, resulting in the high bias voltage between the internal circuit and the frame of the component, resulting in the electrical performance attenuation and a sharp decline in power generation.
3. Component installation method
According to the total amount of solar radiation on the inclined surface and the principle of direct dispersion and separation of solar radiation, it can be concluded that the total amount of solar radiation Ht on the inclined surface is composed of direct solar radiation Hbt scattered from the sky Hdt and ground reflected radiation Hrt, that is, Ht=Hbt+Hdt+Hrt. In the same geographical location, due to the different installation angles of components, the cumulative absorption of sunlight is different, and the cumulative difference of radiation results in the difference of power generation.
4. Weather factors
Weather is also one of the factors affecting the power generation efficiency of components. Under rainy weather and thick cloud, the solar radiation intensity decreases, the cell absorbs less sunlight, and the power generation decreases. Under low irradiation, the weak light response of single crystal is better than that of polycrystal. In the case that the conversion efficiency of solar cell module is certain, the power generation of photovoltaic system is determined by the solar radiation intensity. The power generation of photovoltaic power station is directly related to the amount of solar radiation, and the solar radiation intensity and spectral characteristics change with the meteorological conditions.
5. Shadow occlusion
Components in the process of work due to the shadow part of the shelter and the settlement of dust, bird droppings pollution with differ degree can lead to "hot spot" effect, obscured parts will not provide power contribution and inside the component load and energy consumption at the same time cause local temperature component, overheating areas can cause EVA to speed up the aging become yellow, make the light transmittance declines, Thus, the hot spot is further worsened, leading to the failure of solar cell modules.
6. Temperature coefficient
The temperature coefficient of crystalline silicon cell is generally -0.4% ~ -0.45%/℃, and the temperature coefficient of single crystal is smaller than that of polycrystal. The change of the ambient temperature and the heat generated by the components in the process of working will increase the temperature of the components, and also cause the generation power of the components to decrease.
7. Clean and maintain
When the component is in the field for a long time, dust and other sundries will fall and cover the glass, and a large amount of dust or sand will settle for a long time, which weakens the penetration of sunlight and leads to the rise of the surface temperature of the component, thus affecting the power generation efficiency of the component. When the dust on the surface of the component is serious, the difference in energy generation between before and after cleaning is 5.7%. If the dirt on the surface of the component is not cleaned for a long time, the difference in energy generation can reach more than 10%.
The above analysis is only carried out from the aspects of components themselves and external environmental factors that affect the generation of components. In addition to the factors mentioned above that affect the generation efficiency and generation capacity, there are also power attenuation and generation capacity reduction of components in the working process caused by the electrical system end and other factors. In the future, the factors affecting component power generation need to be solved and improved by process improvement, technology improvement, material research and development and more correlation studies.
