Sun/Solar Driers – Batch, Solid, Not Heat Sensitive


NAICS process:


311423 Dried and Dehydrated Products


Process Brief: Moisture in fruits and vegetables is removed using energy from the sun.

Energy source: Sun

Energy Intensity: None


People have used the sun to dry fruits and vegetables for centuries and it remains the most widely used technique around the world. In its simplest form, sun drying means laying out food on a flat surface. Solar drying systems use solar radiation to heat air that is used for drying. These more advanced systems use electric fans to move the heated air in cabinet-style driers.


The most common use of sun/solar drying in the U.S. is in California where freshly picked grapes are spread on trays that are stacked in the fields. The dry air and heat of the sun dries the grapes in about five days. Outdoor drying works well with high sugar, acidic foods, including many fruits, and is less well suited to vegetables and meats that tend to spoil. Universities and governments continue to research sun/solar drying technologies with the aim of reducing energy use but applications within the U.S. have remained limited.