A comprehensive review on recent development of solar drying technology and applications

Drying is widely used in the food and agriculture industries to preserve food products and crops. Conventional dryers largely use fossil fuels, and their use is discouraged due to environmental pollution, greenhouse gas emissions, and increasing fuel prices. Therefore, solar energy is considered as sustainable and economically viable alternative because it is free, clean, and renewable. This review focuses on the recent advancements of solar drying technology and various methodologies of solar drying processes. The study investigates many aspects, such as design considerations, installation and operation, integration of heat storage materials, nano materials performance evaluation, economic feasibility, and comparative analysis. Both experimental and simulation studies of solar dryers, with and without phase change materials (PCMs), have been reviewed to understand their impact on drying performance. The study further investigates the action of various air heating systems in enhancing drying rate. Hybrid solar dryers have the ability to provide stable and continuous drying conditions, thereby improving drying performance and food product quality. Additionally, the integration of heat storage devices and smart monitoring systems for real-time analysis have been discussed in this study. Overall, solar dryers are considered as a strong potential for sustainable applications in food processing, agro-based industries, and domestic sectors.