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

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 NamgyelEngineering College, Bhutan, and Lund university, Sweden, to design and develop an indirect solardryer. Using solar dryers has many advantages, such as lowering dependency on electricity andfossil 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 theefficiency of the dryer by which the main intended objective is to make the drying rate eventhroughout the drying chamber. In the most of dryer model developed, the prime drawback of thedryer was the nonuniform drying rate among the trays in drying chamber owing to many factorssuch 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 hybriddryer with an integrated heating source that is used to supplement the heated air in sections of thedryer where the drying rate is relatively slow. It also helps maintain the air temperature inside thedryer during cloudy weather conditions. We designed our hybrid solar dryer to be as simple andinexpensive as possible, and better than open sun drying while also shielding the food items fromthe environment. This work provides useful insights into optimizing airflow, improving componentefficiency, and practical recommendations for future advancements, supporting the sustainablepreservation of agricultural products in Bhutan and similar regions.