Experimented plant factory’s air conditioning system performance evaluation

Abstract

The purpose of this study is to experimentally compare the performance of an air conditioning system during part-load and full-load conditions. The air conditioning system is used in a plant factory that is intended for strawberry cultivation. For this purpose, R22 vapour compression cycle air conditioning was installed to provide cool air inside the plant factory. Experiments were carried out under 2 operating conditions, which are part loading and full loading. For the full-loading experiment, 36 Light-emitting Diodes (LEDs) were turned on. There were no strawberry plants inside the plant factory during the experiments. Pressure and temperature of the R22 were measured using pressure transmitters and K-type thermocouples. Average ambient temperature was 29 °C. The air temperature inside the plant factory was set at 15 °C at night and 25 °C during daytime. It was found that the air conditioning system was operated at transient state. The internal air temperature was influenced by the heat transferred from the wall and the LED. Thus, the performance of the air conditioning system was not constant. According to the experimental results, the average superheat degree was 9.2 °C over two hours of experimental time under part-load and it was 13.7 °C at full-load condition for a day experiment. Moreover, the maximum coefficient of performance under part-load and full-load was 4 and 4.2, respectively. The minimum and maximum compressor efficiency were between 20% and 95% when there was part-load and under full-load of the plant factory.