What factors affect the output power of solar pv modules

Solar components are the core part of the solar power generation system. Its function is to convert solar energy into electric energy and send it to the storage battery for storage to promote the work of the load. As an important part of photovoltaic modules, the output power of solar cables is very important. So what factors affect the maximum output power of solar modules?


1.Temperature characteristics of solar modules


Photovoltaic modules generally have three temperature coefficients: open circuit voltage, short circuit current, and peak power. When the temperature rises, the output power of photovoltaic modules will drop. The peak temperature coefficient of mainstream crystalline silicon photovoltaic modules in the market is about -0.38-0.44%/C, that is, for every degree of temperature increase, the power generation of photovoltaic modules decreases by about 0.38%. The temperature coefficient of thin-film solar cells is much better. For example, the temperature coefficient of copper-steel selenium (CIGS) is only -0.1-0.3%, and the temperature coefficient of cadmium (CdTe) is about -0.25%, which is better than crystalline silicon cells.


2. Components aging and attenuation


In the long-term application of photovoltaic modules, there will be slow power attenuation. The maximum attenuation in the first year is about 3%, and the annual attenuation rate in the following 24 years is about 0.7%. From this calculation, the actual power of photovoltaic modules after 25 years can still reach about 80% of the initial power.


3. Dust and rain cover


Large-scale photovoltaic power plants are generally built in the Gobi area, where the wind and sand are relatively large and the precipitation is very small. At the same time, the frequency of cleaning is not too high. After long-term use, it can cause a loss of efficiency of about 8%.


4. Mismatched components in series


Solar modules do not match in series, which can be explained visually by the barrel effect. The water volume of the wooden barrel is limited by the shortest wooden board and the output current of the photovoltaic module is limited by the lowest current among the series modules. In fact, there will be a certain power deviation between components, so component mismatch will cause a certain power loss. The above five points are the main factors that affect the maximum output power of photovoltaic cell modules and will cause long-term power loss. Therefore, the later operation and maintenance of photovoltaic power plants are very important, which can effectively reduce the benefit loss caused by failure.