Effects of various parameters on PV-module power and efficiency

Photovoltaic (PV) modules are one of the most effective, sustainable, and ecofriendly systems. Only a small portion of solar irradiation incident to these modules is converted into electricity. The rest of the irradiation is converted into heat, which overheats the PV module and reduces its performance. In this experiment, various operating parameters such as irradiation intensity, cooling fluid mass flow rate, humidity, and dust have been varied to observe their effects on PV module performance. A heat exchanger was used on the back surface of the PV module to cool cell temperature. At 1000 W/m(2) irradiation level without cooling, cell temperature increased to 56 degrees C; the output power decreased to 20.47(W); and the electrical efficiency decreased to 3.13%. A decrease in output power of about 0.37 W and a decrease in electrical efficiency of 0.06% per 1 degrees C increase in solar cell temperature were observed. For every 100 W/m(2) increase in the irradiation intensity, the output power increased by 2.94 W, with a 4.93 degrees C increase in solar cell temperature. The reduction of the module temperature to 22.4 degrees C increased the output power by 8.04 W and increased the electrical efficiency by 1.23% by applying water cooling on the PV module. This value is 27.33% higher than the output power and efficiency produced without cooling. The output power decreased by about 3.16W with a 20% increase in relative humidity, and the output power is reduced by 7.70 W because of dust falling on the surface of the solar module. In conclusion, the parameters of solar cell temperature, irradiation intensity, cooling fluid mass flow rate, humidity, and dust affect PV-module performance. (C) 2015 Elsevier Ltd. All rights reserved.