Performance Evaluation of Tunnel and Indirect-Type Solar Dryers: A Study Using Potato Slices

This study presents the comparative performance of a solar tunnel dryer and an indirect-type solar dryer for drying potato slices. Experiments are conducted to assess moisture removal efficiency, drying time, and energy efficiency. The initial moisture content of potato slices of 82% wet was reduced to 34.9% for solar tunnel dryer and 45.2% for indirect-type solar dryer. Both systems' drying times and temperature profiles are recorded. Results shows that the solar tunnel dryer achieves faster drying compares to indirect-type solar dryer, due to its higher and consistent temperatures. Energy efficiency calculations reveals that the solar tunnel dryer utilizes available solar energy more effectively, with an efficiency of 11.41%, compares to 9.60% for the indirect-type solar dryer. Both systems effectively reduce the weight of potato slices but solar tunnel dryer demonstrated superior performance in maintaining uniformity. The study concludes that the solar tunnel dryer is more suitable for large-scale and time sensitive operations, whereas the indirect-type solar dryer is a cost-effective solution for small-scale applications. This work highlights the potential of solar drying technologies as energy-efficient and sustainable methods for food preservation.