Effects of operational conditions on the energy efficiency of photovoltaic modules operating in Malaysia

Photovoltaic (PV) modules convert a small portion of solar radiation into electrical energy and convert the rest into heat. As a result, the temperature of these modules is increased and their electrical efficiency is degraded. In this study, the effects of various operating parameters, such as solar cell temperature, irradiation intensity, mass flow rate of cooling water, humidity, and dust, on the output performance of a PV module are investigated under outdoor operating conditions. A finned tube is placed at the bottom of the PV module for cooling. Results show that the electrical efficiency of the module decreases by 5.82% as solar cell temperature increases by 26.10 °C. The electrical efficiency also decreases by approximately 0.22% as the temperature of the PV module increases by 1 °C. As irradiation intensity increases by 100 W/m2, the solar cell temperature increases by 3.82 °C and the output power increases by 3.14 W, but the efficiency decreases by 0.85%. In summary, solar cell temperature, solar irradiation intensity, mass flow rate of cooling fluids, humidity, and dust significantly affect the performance of PV modules.