Design, Development and Performance Analysis of Solar-Electric Hybrid Dryer

Abstract

Bhutan, like any other mountainous country, is facing serious issue in food preservation.

Conventionally, open air sun drying is preferred for drying as it is environment friendly and cost-
effective. Meanwhile, open-air drying has a few drawbacks, including dust contamination,

hardening, discoloration of products and longer drying time. This, in turn, led Jigme Namgyel
Engineering College, Bhutan, and Lund university, Sweden, to design and develop an indirect solar
dryer. Using solar dryers has many advantages, such as lowering dependency on electricity and
fossil fuels and creating a cost-effective and environmentally friendly food preservation solution.
Numerous designs were developed every year and many upgrades were done to improve the
efficiency of the dryer by which the main intended objective is to make the drying rate even
throughout the drying chamber. In the most of dryer model developed, the prime drawback of the
dryer was the nonuniform drying rate among the trays in drying chamber owing to many factors
such as the number of trays, weather contingencies, tray placements and duration of the drying time.
In this study, we present design, development, and performance analysis of a solar-electric hybrid
dryer with an integrated heating source that is used to supplement the heated air in sections of the
dryer where the drying rate is relatively slow. It also helps maintain the air temperature inside the
dryer during cloudy weather conditions. We designed our hybrid solar dryer to be as simple and
inexpensive as possible, and better than open sun drying while also shielding the food items from
the environment. This work provides useful insights into optimizing airflow, improving component
efficiency, and practical recommendations for future advancements, supporting the sustainable
preservation of agricultural products in Bhutan and similar regions.