Experimental results of a solar cooling system for greenhouse climate control
Greenhouse microclimate control is important to reach high production yield and low environmental impacts. Ventilation, shading and evaporative cooling are methods for controlling air temperature and relative humidity inside the greenhouse. Ventilation and shading can be not sufficient to remove the excess heat, while evaporative cooling is based on the exploitation of huge amounts of water. In order to enhance the sustainability of the greenhouse industry, renewable energy sources can be exploited. Solar absorption systems can be used for greenhouse cooling in areas with high outdoor temperatures and solar radiation levels. These systems take advantage of the simultaneity between the solar energy availability and the greenhouse cooling demand allowing the reduction of conventional electricity and water consumption. They can be used in remote areas where conventional cooling is difficult and where there is abundant solar energy. This paper presents the results of the application of a solar cooling plant for climate control of a greenhouse. The system is sited at the University of Bari, Italy. The experimental plant consists of a Mediterranean greenhouse, having a surface of 300 m2 and by a single effect LiBr-H2O absorption chiller fed by evacuated-tube solar collectors. The application of two different localized distribution of cold inside the greenhouse was studied in order to evaluate the reduction of air temperature close to the cultivation area. A reduction of the greenhouse air temperature up 5.0°C was obtained.
Puglisi, G., Vox, G., Campiotti, C.A., Scarascia Mugnozza, G. and Schettini, E. (2020). Experimental results of a solar cooling system for greenhouse climate control. Acta Hortic. 1296, 1107-1114
absorption unit, evacuated tube solar collectors, climate control, renewable energy sources