Deep bed drying performance on paddy using hybrid infrared-solar dryer

Hybrid infrared-solar dryer has a potential for drying fruits, vegetables, and grains such as paddy. This study aims to assess the performance of hybrid infrared-solar dryer on paddy in different of deep layer. Three different infrared heaters were used with a power of 25 W, 50 W, and 100 W. The hybrid infrared-solar dryer equipped with sensors placed in an open space so that sunlight can reach the drying chamber. The paddy samples were dried in different of deep layer (2 cm, 4 cm, 6 cm) until it reaches a moisture content of 14%. The input sensors in the drying chamber such as temperature, humidity, and moisture content were recorded using microcontroller and stored in Microsoft Excel® using the Parallax Data Acquisition tool. The algorithm was developed in order to control the heater from the input of temperature and humidity sensors by adjusting turn on/off relay. The study confirmed that the infrared heating power of 100 W is recommended for paddy drying if the ambient temperature is unfavourable (temperature less than 30°C). In general, the hybrid infrared-solar dryer with a power of 25 W-100 W has a potential to dry paddy quickly at a thickness of 2 cm-6 cm with a time range of 90-150 minutes.