Solar dryers or Solar dehydrators are used to eliminate the moisture content from crops, vegetables, and fruits. The solar dryer consists of a box made up of easily available and cheap materials. The top surface of the dryer is covered by transparent glass. Since the cabinet is insulated, the inside temperature of the dryer is raised. The air is ventilated by a fan through the hole at the top of the dryer. As the inside air gets warm, it rises by the natural circulation process and removes the moisture from the fruits, vegetables, and the crops placed in trays inside the box. To fill the vacuum, fresh air comes in by a forced draught process and the process continues.
The advantages of the solar dryers are:
(1) easy to assemble,
(2) cheap available materials can be used,
(3) simple to operate, maintain and control, and
(4) light in weight