An experiment-based comparison of different cooling methods for photovoltaic modules

Abstract

Abstract Temperature effect on the performance of a photovoltaic module represents a major concern for expanding the use of solar energy, especially in hot areas. Cooling the PV module is considered an effective method of increasing efficiency by reducing the module cell temperature. An experimental set-up is developed to investigate the effectiveness of different cooling techniques including air cooling, evaporative cooling and water cooling. A comparative study is made among the cooling techniques by simultaneous recording – for the first time – the performance the modules cooled by the different techniques. Experimental measurements dictated that the reduction of the module cell temperature recorded 5 %, 16 %, 17.25, 39.6 % and 44.8 % for passive air cooling, active air cooling, water cooling, evaporative cooling using sprinkler and nozzles, respectively. The best cooling conditions were achieved by evaporative cooling using film of domestic tap-water from nozzles with flow rate of 90–190 L/h/module. The experimental results showed an increase in electrical efficiency of 1.8 % for continuous- against 1.7 % for intermittent-evaporative cooling using water-film from nozzles. The corresponding increase in electrical efficiency on using evaporative cooling by sprinkler is 1.6 % for continuous- against 1.3 % for intermittent cooling. This means there is no significant difference in efficiency values between continuous and intermittent evaporative cooling. This favors the use of intermittent cooling decreases the cost without sacrificing the efficiency value. This makes it possible to identify the recommended method for cooling modules serving in areas of hot weather and moderate climates.