A solar dryer technology and its development

Abstract

       This academic review article is on solar dryer technology aimed to provide development and to promote a use of solar dryer technology in Thailand. The article reveals 3 methods of solar reception, namely direct solar reception, indirect solar reception and mixed solar reception. Two systems of air circulation used in this solar dryer technology were a passive system and an active system. The main factors enhancing performance of the solar dryer were temperature, air velocity and humidity in the system. A development of system stability and duration of solar drying can provide more benefits of sunlight. An adaption of solar heat water system with a heated water tank and a greenhouse is worth experimenting to produce heat in drying process of mixed active solar drying and mixed passive solar drying. The produced temperature varies according to the capacity of each type of solar collectors meanwhile water is used as either a heat accumulator or an accelerator with heat pumping system depending on types of materials appropriate for solar drying.