Characterisation of copper indium gallium diselenide solar module in the Ugandan climate

Abstract

The photovoltaic solar energy from copper indium gallium diselenide (CIGS) solar module is one of the most promising sources of solar energy for large scale production of clean energy at competitive prices. The focus of the study was to determine the performance of CIGS solar module in terms of its performance parameters in the tropical region. The goal of this dissertation was hence to characterise the performance of CIGS solar modules in the Ugandan climate. The performance of the CIGS module was assessed when put out doors by measuring the current-voltage (1-V) characteristic of the device. A variable resistor was connected to the CIGS module and was varied from minimum (0 Ω) to maximum (l00 Ω) and the corresponding current and voltage were measured. The electrical performance parameters such as short circuit current, open circuit voltage, maximum power, fill factor and efficiency were then obtained from 1-V characteristic curves. The short circuit current obtained was l.03A that is 1.9% lower than the rated value. The open circuit voltage obtained was 19.25V that is 35.8% lower than the rated value. The maximum current obtained was 0.7 lA that is 12.3% lower than the rated value. The maximum voltage obtained was 13.4V that is 37.9% lower than the rated value. The maximum power obtained was 9.5W that is 36.7% lower than the rated value. There was no change in the fill factor. The efficiency obtained was 6.1 % that is 24.7% lower than the rated value. The study shows that out of the seven parameters it was only the fill factor which had the same value with the rated value. The short circuit current was close to the rated value while other parameters were significantly lower than the rated value varying between 12.3% and 37.9%. Basing on the findings of this study, it is recommended that a further study should be done over a longer period of time for example a year in both dry and wet seasons to cross check the reliability of the findings of this study. The results of this study will be useful to compare the performance of this type of module with others in the market to find out if they would give similar values. Current-voltage (1-V) characteristics measurements under the dark should also be considered to determine the performance of the CIGS solar modules. This would determine other electrical parameters such as series resistance, shunt resistance and diode parameters (ideality factor and reverse saturation current).