Use of a phase change material (PCM) for the reduction of peak temperatures in a model greenhouse

In this study, the possibility of employing a phase change material for primarily the reduction of peak temperatures in summer in greenhouses was investigated. The PCM used had a melting temperature of approximately 23 degrees C and a latent heat of 216 kJ/kg. The total amount of the PCM used was 192 kg. In the application, the greenhouse with the PCM store, which had a ground area of 13.5 m(2) was compared with a same-sized greenhouse with the same plant (grown only in summer application) but without the PCM store. The energy storage and release were thermostatically controlled. The results of the study showed that the air temperature in the greenhouse with PCM store was approximately 3 degrees C lower than that in the control greenhouse during the day time and vice versa at night. Average solar collection efficiency of the PCM store was approximately 30 %. Fruit yield in the PCM greenhouse was almost twice that in the control one.