Experimental investigation of the performance of a large-scale greenhouse type solar dryer for drying chilli in Thailand

Solar drying is considered to be a useful solar energy technology for developing counties. In this work, the performance of a large-scale greenhouse type solar dryer for drying chilli was investigated. The dryer has a parabolic shape and it is covered with polycarbonate sheets. The base of the dryer is a concrete floor with an area of 8×20 m2. Nine DC fans powered by three 50 W solar cell modules were used to ventilate the dryer. The dryer was installed at Ubon Ratchathani, Thailand. Three batches of chilli were dried in the dryer. It was found that five hundred kilograms of chilli with the initial moisture content of 74% (wb) were dried within 3 days while the natural sun dried needed 5 days. The chilli dried in this dryer was completely protected from insects, animals and rain. In addition, good quality of chilli was obtained.