Due to lack of cold storage facilities and packed food processing facilities in developing countries most of the vegetables and other crops get rotten within week of harvest. By drying the vegetables and crops they can be preserved for longer periods and the supply of vegetables and crops can be extended up to six month or longer.
This is an idea to improve conventional solar dryer efficiency by utilizing thermal storage capacity of Molten Salt so that drying of agriculture crops can take place at night and drying time gets reduced by 50 percent.
The set up consists of (fig 1) Air convection type Solar Dryer where crops are loaded in a tray. The unit is connected to a Heat Exchanger (Fig 3) which transfers heat of molten salt to air blown by Solar PV air blower (fig 4 ) at night. The molten salt takes heat from a Parabolic mirror reflector (fig 2) in the day time and stores it. As the night falls the heat from the molten salt is exchanged in the heat exchanger and fed to the solar dryer chamber. Thus the solar dryer works 24 hrs and the drying of Agri –crop takes place during the night.