Development of a biomass energy dryer assisted with solar energy for farmers in off-grid communities

The objectives of this research are to design and construct a biomass energy dryer assisted with solar energy for farmers in off-grid communities and to evaluate the performance of the dryer. The dryer consists of a boiler, drying chamber and solar panels. A compressed sponge was used as a drying product. The air temperature distribution and product moisture uniformity inside the drying chamber were measured. The apparatus was tested in three energy modes, solar energy mode, biomass energy mode and biomass/solar energy assisted mode. Drying using biomass/solar energy assisted mode gave a better drying performance compared to the other modes due to the uniform moisture content and air temperature. The average temperature difference between the top and bottom tray was less than 3°C. The average moisture content between the top and bottom tray was very close, less than 0.8% db. In addition, this drying mode can reduce product contamination from smoke ash and combustion