Recent developments on photovoltaic thermal drying systems: a clean energy production

With the increase in population globally, a big problem has been raised, which is food supply. A remedy to this problem is to use an ancient practice of sun drying to preserve harvests, vegetables, and fruits. Several types of dryers are being developed for drying agricultural commodities. They do, however, demand much energy, which is typically obtained from polluting fossil fuels. Producers, as well as researchers, are encouraged to look for alternate options because of environmental issues and the risk of fossil fuel depletion. Continual solar energy can be helpful in drying applications because it is widely available freely in most parts of the world. Solar dryers come in various sizes and designs, and they may be used to dry a wide range of products. Farmers will find a variety of driers available to meet their demands. A thorough examination of the various designs, methods of construction, and operating ideologies of the numerous sun-drying devices mentioned previously is provided. This study emphasizes the hybrid photovoltaic thermal solar dryer because of its high electrical and thermal efficiency, good mitigation of carbon dioxide levels, giving a good product with a high drying rate and less payback time. The greenhouse solar dryer is found to be best adapted to the requirement in rural locations, where there are more agricultural products accessible for drying and space is also readily available. The future scope and recommendations section of this study will assist researchers in developing an efficient photovoltaic thermal solar dryer collector system that is economical and has good electrical and thermal efficiency for large-scale applications. Graphical abstract