Chapter 9: Solar and Open-air Drying

Traditional forced-air dryers tend to be energy-intensive. Many small-scale dryers rely on electrical energy which can be prohibitively expensive. Although solar drying is not a new technique, it has gained renewed attention as an alternative to other methods of drying due to its avoidance of other costly fuels. Solar drying is not without its challenges and does have its limitations, which are discussed in this chapter. An evolutionary approach is taken to show how solar dryers can be designed to optimize their operation and improve their efficiencies. In a similar manner, the design of open-air dryers is studied. The performance of these dryers is assessed and demonstrated using mathematical models derived from real-life experimentation.