Analysis of Performance Parameters of Amorphous Photovoltaic Modules under Different Environmental Conditions

Abstract

The effects of temperature and radiation intensity on the performance parameters of amorphous hydrogenated silicon (a-Si:H) photovoltaic module have been investigated. An outdoor experimental setup is installed to carryout a series of I-V curve measurements under different irradiance and temperature conditions for the module. A numerical model which considers the effect of series and shunt resistances is developed to evaluate the different parameters of PV modules. Orthogonal distance regression (ODR) algorithm is adapted for fitting I-V measurements and extracting module parameters from I-V measurements. The values of module parameters, series resistance R s , shunt resistance R sh , diode ideality factor n and reverse saturation current I o determined from I-V measurements at different irradiation intensity and temperature range are in good agreement with the corresponding parameters obtained from the developed numerical model. The module parameters extracted from I-V measurements are employed to calculate the module performance parameters, i.e. open circuit voltage V oc , fill factor FF and module efficiency h at different irradiation intensity and temperature range. Present results indicate that the module parameters have a significant effect on module performance. Also, the behavior of V oc is completely different at higher temperatures. Key words : Amorphous module parameters; Ideality factor; Series resistance; Shunt resistance