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Smart Grid and Renewable Energy, 2011, 2, 375-387 doi:10.4236/sgre.2011.24043 Published Online November 2011 (http://www.SciRP.org/journal/sgre)
Investigation of the Performance of CIS Photovoltaic Modules under Different Environmental Conditions Kandil M. Kandil, Majida S. Altouq, Asma M. Al-asaad, Latifa M. Alshamari, Ibrahim M. Kadad, Adel A. Ghoneim* Applied Sciences Department, College of Technological Studies, Shuwaikh, Kuwait. Email: *
[email protected] Received July 1st, 2011; revised July 27th, 2011; accepted August 4th, 2011.
ABSTRACT This work investigates the effects of temperature and radiation intensity on the parameters of a copper indium diselenide (CIS) photovoltaic module. The module performance parameters are determined from calculated module parameters. 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 Rs, shunt resistance Rsh, diode ideality factor n and reverse saturation current Io 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 Voc, fill factor FF and module efficiency at different irradiation intensity and temperature range. Present results indicate that the largest drop in open circuit voltage Voc due to about 20˚C increase in temperature is approximately 8.8% which is not compensated for by the relatively small increase in short circuit current, (2.9% in Isc), resulting in a reduction in maximum power of about 6.3%. Results let us conclude that the shunt resistance RSh increases with radiation at low radiation values (400 W/m2), RSh begins to decease sharply and dramatically. Also, as the light intensity incident on the solar module increases, the series resistance and the output voltage decrease. When the irradiance intensity increases, the series resistance decreases but with a very low rate at the two studied temperatures ranges. The low rate decrease of Rs is found to have little effect on module performance in comparison with the significant change of other module parameters. The ideality factor n and saturation current Io decrease first sharply in the low range of radiation intensity (
