Investigation of optimization of solar energy refrigerator with natural humidifier

Cold chain processes of horticultural products in tropical countries is very urgent to maintain product quality. In Indonesia, the temperature and humidity are relatively high, so that the deterioration of horticultural products is very fast. Because of the high humidity, this condition can highly possibly use a natural humidifier for a cold room by purging humid ambient air to the refrigerator cabin with the best certain time. Meanwhile, as a tropical country, solar energy has good reliability to be developed. This study aims to determine the performance of the medium temperature refrigerator with a natural humidifier using solar energy as energy source. This research was conducted as an experimental investigation. The rig has been built completely with measurements and instrumentation for precise temperature and humidity control. The results showed that the system reached a quite good coefficient of performance (COP), with the thermodynamically COP of 3.6. However, humidifiers contribute a cooling load which can affect the temperature increase of 1o C - 1.5o C in the cooling system. Further studies will examine the optimization of the refrigerator system with natural humidifiers with low electricity consumption and eco-operating conditions with the best combination of temperature and humidity to keep the product of good quality in a long storage time.