We know the PV modules are usually tested under standard conditions (i.e., standard test conditions (STC) are 1000 W/m 2, AM1.5, 298.15 K), but the actual operating temperature is much higher and there are uncertainties . As one of the core components of PV modules, solar panel performance is strongly influenced by its temperature.
The best module operated at a NOCT of 33°C, the worst at 58°C and the typical module at 48°C respectively. An approximate expression for calculating the cell temperature is given by 2: where: S = insolation in mW/cm 2. Module temperature will be lower than this when wind velocity is high, but higher under still conditions.
A PV module will be typically rated at 25 °C under 1 kW/m 2. However, when operating in the field, they typically operate at higher temperatures and at somewhat lower insolation conditions. In order to determine the power output of the solar cell, it is important to determine the expected operating temperature of the PV module.
It is clear that any simulator of a PV array performance needs the cell/module operating temperature in order to translate the performance of the modules from the standard rating temperature of 25 °C to the modules' performance at operating temperatures.
Conclusions Knowledge of PV module temperature is essential for an accurate assessment of module performance as solar module efficiency decreases by about 0.4% per degree Celsius. The accuracy of the temperature is important because a 2.5% error in the estimated temperature would lead to about a 1% error in the module performance.
In order to determine the power output of the solar cell, it is important to determine the expected operating temperature of the PV module. The Nominal Operating Cell Temperature (NOCT) is defined as the temperature reached by open circuited cells in a module under the conditions as listed below: Mounting = open back side.