The relevant factors affecting the output power and attenuation of PV modules are as follows:
1, the quality of photovoltaic modules: due to cell crack, black core, oxidation, virtual welding, and backplane and other material defects and long-term use of aging and other factors, resulting in solar panels in the long-term operation of the power is affected, resulting in solar panel power generation The amount is low.
2, PID effect: solar panels in the long-term work outside, because the water vapor penetrates into the interior of the solar panel through the backing plate, causing EVA hydrolysis, acetic acid ions cause metal ions to precipitate in the glass, resulting in a high bias between the internal circuit and the frame of the solar panel When the voltage is set, the electrical performance is attenuated and the amount of power generation drops sharply.
3. Installation method of photovoltaic solar mounting bracket support: The total solar radiation on the inclined surface and the principle of direct dispersion of solar radiation can be obtained: the total amount of solar radiation on the inclined surface Ht is the direct solar radiation amount Hbt sky scattering amount Hdt and the ground The amount of reflected radiation is composed of Hrt, that is, Ht = Hbt + Hdt + Hrt. In the same geographical location, due to the difference in the PV solar mounting angle of the bracket, the cumulative amount of absorption of sunlight is different, and the cumulative difference in the amount of radiation causes a difference in power generation.
4. Weather factors: The weather is also one of the factors affecting solar panel power generation efficiency. In the rainy weather and thicker clouds, the intensity of sunlight is reduced, the solar light absorbed by the cell is less, and the power generation is reduced. The low-light response of single crystal is better than polycrystalline under low irradiation. In the case where the conversion efficiency of the solar solar panel is constant, the amount of power generated by the photovoltaic system is determined by the radiation intensity of the sun. The amount of electricity generated by a photovoltaic power plant is directly related to the amount of solar radiation. The radiation intensity and spectral characteristics of the sun change with meteorological conditions.
5, shadow occlusion: solar panels in the working process due to partial shadow blocking and dust deposition degree, bird faecal pollution will cause "hot spot effect", the occluded part of the solar panel will not provide power contribution and in the solar panel The internal energy consumption load causes the local temperature of the solar panel to rise. The overheated area can cause the EVA to accelerate aging and yellowing, which reduces the light transmittance of the area, thereby further worsening the hot spot, resulting in intensification of solar cell solar panel failure.
6. Temperature coefficient: The temperature coefficient of the crystalline silicon battery is generally -0.4% to -0.45%/°C, and the single crystal temperature coefficient is smaller than polycrystalline. Changes in the ambient temperature and the heat generated by the solar panel during operation cause the temperature of the solar panel to rise, which also causes the power generation of the solar panel to decrease.
7. Cleaning and maintenance of photovoltaic panels: Solar photovoltaic panels are in the wild for a long time. Dust and other debris will fall on the glass, and a large amount of dust or dust will settle for a long time, which will weaken the penetration of sunlight and lead to the surface of solar panels. The increase in temperature affects the efficiency of solar panel power generation. When the surface of the solar panel is more dusty, the difference between the power generation before and after cleaning is 5.7%. If the cleaning is not carried out for a long time, the difference in the amount of dirt generated in the surface of the solar panel can reach more than 10%.
The above analysis only affects the solar panel power generation factors from the perspective of the solar panel itself and the photovoltaic solar mounting bracket installation, as well as the external environmental factors. In addition to the above-mentioned factors affecting power generation efficiency and power generation, there are also due to the electrical system end and others. Factors that cause solar panels to lose power during operation, reduce power generation, and so on.