Design, Construction And Testing Of An Evaporative Cooling Facility For Storing Vegetables

A solar powered evaporative cooling system of 0.6 m3 capacity was designed and constructed to increase the shelf life of stored vegetables. The evaporative cooler was tested and evaluated using tomato (Roma). The equipment operates on the principle of evaporative cooling and increasing the relative humidity (RH) in the preservation chamber. The storage system was made up of aluminum sheets of 1 mm thick while a side of the system is made of jute pad which get moist by water flowing through a series of perforated pipe from the reservoir located at the top of the storage system. The water flows with the influence of gravity. The RH and weight loss of tomato was statistically analyzed using student T – test and the result revealed that there was significant difference in using the evaporative cooling system for storing tomatoes as compared to ambient condition. The average cooling efficiency was found to be 83 %. The temperature in the system dropped drastically when compared to the ambient condition which ranges from 6 to 10°C and the relative humidity in the cooling chamber increased considerably to 85 %. However, the testing of the evaporative cooling system shows that the tomatoes can be stored for an average of five (5) days with negligible changes in weight, color, firmness and rotting as compared to ambient condition which started rotting after three (3) days. Hence, it is on this note that farmers, house holders and tomatoes processing factories should adopt the use such evaporative cooling system for the storing of fresh tomatoes as this increases the shelf life of tomatoes.