In order to develop greenhouse cooling and water saving technologies suitable for desert climate, the performance evaluation of the cooling packages and condensate water recovery from cooling fan coil unit. As a result of the application for tomato greenhouse in summer, the root zone temperature of root zone cooling+duct cooling case and root zone cooling case was 25℃ during the day and 20℃ at night, which was suitable for tomato growth. When the nutrient solution tank was cooled, the temperature of the nutrient solution was maintained at 20 degrees, but otherwise, the temperature exceeded 30℃, causing the root zone temperature to rise. Condensate water recovery per fan coil unit was 93L on average per day in August, and was proportional to relative humidity in greenhouse and temperature difference between dew point temperature and the surface temperature of heat exchanger. Tomato growth was found to be improved in the order of root zone cooling+duct cooling, root zone cooling, duct cooling and control. It was analyzed that the yield of root zone cooling+duct cooling, root zone cooling and duct cooling increased by 35%, 28% and 11%, respectively, compared to the control.

A cooling system that applies double collision jet is studied. To create a jet, a square edge type nozzle is used as its shape. The impinging jet that composes a cooling system which applies double impinging jet is created in the single nozzle and double nozzle that correspond to each LED where the cooling zone exists. The distance between the 2nd nozzle and LED with heat sink is where the LED package is established. The main variation and the standard is examined for four different cases through the way out diameter of 1st nozzle. The examined velocity distribution and temperature distribution about the cooling system consisted of single and double nozzle. It was found that an individual LED consisting of double nozzle was efficient.