Development and performance evaluation of solar-powered cold storage system for perishable agricultural products

In the context of food-energy nexus security, current study designs/develops an on-grid solar-powered cold storage system (CSS) integrated with internet of things (IoT) for perishable agricultural products. Size of 3.3 kW of the on-grid solar PV system is estimated for successful operation of the CSS. Performance of the developed system is evaluated in case of tomato, capsicum and mango storage from viewpoints of maintaining T/RH, vapor pressure deficit (VPD), physiological weight loss (PWL), CO₂ generation, ethylene (C₂H₄) generation and physical appearance (for shelf-life). Moreover, the study evaluates energy available/generation by solar PV system, and unit energy consumption (UEC) by the CSS. As per results, the T and RH is maintained between 16 °C-29 °C and 75 %-99 %, respectively with VPD of 0.03-0.63 kPa for studied agricultural products. The PWL by the agricultural products is ∼3 times less while shelf-life is ∼4 times higher under storage conditions as compared to outside conditions. Consequently, the CO₂ and C₂H₄ generation are maintained between 21.97-229.93 mg/kg/h and 0-9.71 μL/kg/h, respectively. The UEC is observed of 0.01 kWh/kg/day (during tomato storage), and 0.02 kWh/kg/day in case of capsicum and mango storage. Additionally, payback period, and levelized cost of electricity is computed as 2.41 years, and 0.02 $/kWh, respectively.