A comprehensive insight into solar drying systems for agricultural and industrial applications

The need for the utilization of renewable energy in place of conventional sources is inevitable due to the ever-growing energy demand of a rapidly increasing population. Solar energy is the most viable alternative for substantially bridging the gap between demand and supply of conventional energy. Food and industrial products need to be dried for better storage and transportation. Using solar energy to dry agricultural and industrial products has enormous promise in rural as well as in urban areas as it is economical and energy efficient. This review paper delivers insight into various emerging technologies in the vast field of solar dryers, along with a brief introduction to their design and applications. The present work highlights shortcomings and comprehensively reviews the studies on direct solar dryers, indirect solar dryers, mixed-mode solar dryers, greenhouse solar dryers and hybrid solar dryers with their applications. The paper covers the studies performed on solar dryers, mainly in agricultural and industrial aspects, along with recent advancements and their repercussions on the overall performance of solar dryers and highlights the evaluative corners for uplifting their efficiencies.