Solar indirect dryer technology has long been recognized for its historical significance and cost-effectiveness in agricultural practices. Solar dryers are being developed as a sustainable solution for reduction of food scarcity particularly for drying food and storing it for longer durations. Among the various solar drying methods, solar indirect dryers stand out for their efficiency and economy, offering a reliable means of preserving food quality and availability during off-season periods. Despite their effectiveness, the current monitoring and control procedures for solar indirect dryers heavily rely on manual site visits by researchers, mainly due to the limitations of sensor-based systems in operation. In response to these challenges, this research proposes a transformative approach by integrating advanced sensors for continuous monitoring of temperature and humidity at multiple points within the solar indirect dryer. Additionally, the implementation of a smart data logger is introduced to automate the monitoring and recording processes,
TopIntroduction
To align population growth with the current food supply and maintain a healthy equilibrium, it is imperative to minimize food loss during harvesting and post-harvest processes. The utilization of outdated processing methods and insufficient storage facilities has been identified as contributing to a decline in both the quality and quantity of agricultural products (Petrunina et al., 2023). Horticultural crops, characterized by their high water content, are susceptible to drying, shriveling, wilting, and mechanical stress, necessitating their cultivation in greenhouses (Firdous, 2021).
Research organizations estimate that, post-harvest, a significant portion (20 to 30 percent) of fresh horticultural produce is lost, posing substantial economic and societal consequences (Dhatt & Mahajan, 2007). Employing diverse preservation techniques, such as drying, cooling, fermentation, canning, pasteurization, freezing, irradiation, and the use of various chemicals, extends the storage lifespan of agricultural products, mitigating losses and enhancing overall food security. Adopting modern preservation methods is essential for sustaining food availability and addressing the challenges posed by traditional practices and inadequate storage infrastructure.
Figure 1. Importance of IoT in agriculture sector
Drying is the method of reducing moisture in a product to an optimal level, inhibiting the growth of yeast, mold, and bacteria and thereby extending the product's shelf life (Saikia et al., 2023). This enables prolonged storage of the product. Among the pivotal steps in preserving fruits and vegetables, the drying process offers versatility in its implementation. Energy for drying can be sourced from various outlets, including fossil fuels, electricity, natural gas, biomass, and solar energy. The increasing popularity of renewable energy sources among farmers is seen as a means to enhance productivity (Pestisha et al., 2023).
The imperative to transition to renewable energy sources for drying arises from the rapid depletion of fossil fuel supplies (Gautam et al., 2023) and the escalating cost of electricity (Almasoodi, 2023). Solar dryers exemplify the use of renewable energy. These dryers, employed in the drying of agricultural products, are acknowledged for their cost-effectiveness and minimal environmental impact (Hussain & Lee, 2023). The primary advantage of solar dryers lies in ensuring that dried items maintain specifications, dried in a secure environment. Most solar dryers boast low maintenance costs, no expenses related to biofuel usage, time efficiency, high-quality dried products with minimal space requirements, and the ability to regulate air conditions. Therefore, when applied in drying agricultural products, solar dryers emerge as both highly cost-effective and environmentally beneficial.
Furthermore, the Internet of Things (IoT) is transforming the agricultural sector by offering a diverse array of services across multiple domains (Muzammal & Murugesan, 2018, 2021). Figure 1 vividly illustrates the paramount role of the Internet of Things (IoT) in the agricultural sector, highlighting its significance in optimizing and augmenting the efficiency of diverse processes (Humayun et al., 2020). Through the integration of IoT technologies, farmers and agricultural enterprises can leverage real-time data, automation, and connectivity to enhance productivity, optimize resource utilization, improve crop quality, and mitigate risks (Alberti et al., 2019; Muzammal & Murugesan, 2020; Yu et al., 2022). The effectiveness of a solar dryer is contingent upon various conditions and parameters, including meteorological factors, collector orientation, cover material type and size, collector length and depth, and the nature of the absorber material. There is an urgent need to enhance the overall productivity of the industry by expanding the use of agricultural engineering and technology for more precise monitoring and management of environmental conditions (Sujatha et al., 2021).