(1) Since the output power of solar modules depends on factors such as solar irradiance and solar cell temperature, the measurement of solar modules is carried out under standard conditions (STC), which are defined as:

Air quality AM1.5, light intensity 1000w/m2, temperature 25 ℃.
(2) Open circuit voltage: use 500W halogen lamp, 0 ~ 250V AC transformer, the light intensity is set to 38000 ~ 40000 lux, the distance between the lamp and the test platform is about 15-20cm, and the direct test value is open circuit voltage;
(3) Under this condition, the maximum power output of the solar cell module is called the peak power. In many cases, the peak power of the module is usually measured by the solar simulator. The main factors affecting the output performance of solar cell modules are as follows:
1) Load impedance
2) Sunshine intensity
3) Temperature

4) Shadow