Climatization of The Greenhouses in Arid Climate Regions: A Case Study of Şanlıurfa

Abstract

In greenhouses, climate control is important for energy savings and the quality of the crop yield. At times when the average daily temperature is between 12 and 22 °C,  the climate values desired by the plants can be maintained at the biological optimum by natural ventilation, one of the most cost-effective climate control methods. If the average daily temperature rises above 22 °C, climate control measures such as additional shading and evaporative cooling for greenhouse ventilation are essential. In this study, according to the TS 825 standards in Turkey,  based on the long-term hourly climate data (temperature, solar radiation, humidity, and wind speed) of Şanlıurfa, the city with the highest value of cooling degree days.  and using the energy balance and psychrometric equations, the temperature values required for the continuity of vegetative production in greenhouses with the air conditioning measures (ventilation, [ventilation + shading], and evaporative cooling) used in hot periods will be determined. Consequently, it was determined that the ambient temperature in the greenhouse can be maintaned at 27 ^oC until mid-May in large-volume greenhouses with  50% shading and 40% ventilation and that evaporative cooling is mandatory for production in the greenhouse after mid-May under the climatic conditions of Şanlıurfa, and that the temperature can be maintaned at 27 ^oC in July in the large-volume greenhouse with 80% pad efficiency.