Techno-economic analysis of off-grid solar-driven cold storage systems for preventing the waste of agricultural products in hot and humid climates

Abstract

The spoilage of agricultural products during the post-harvesting process in countries with hot and humid climate is a very serious challenge. The high volume of fruits produced in the hottest months of the year in a short period causes a high percentage of fruit rot. This is, especially, more challenging for countries with low quality electricity grids, e.g. India. This study proposes the use of in-site off-grid solar-driven cold storage systems integrated with an auxiliary heater for year-round storage of agricultural products (potato in an Indian farming area, just as a reference case). The purpose of the research is to assess which type of solar collector is the best solution from the energy and economic point of view. For this, the required annual cooling load of a 5 TR cold storage of potato is calculated and then, the effect of different types of collectors in heat provision on the performance of the cold supply unit is investigated. The results show that when the system is integrated with PTCs, the performance of the system is much less effective compared to when integrated with ETCs and FPCs. From an energy point of view, FPC, ETC performed at the higher energy efficiency, while in the economic assessments, considering the technical effectiveness of different configurations, an ETC-integrated arrangement reveals the best economical solution with a payback period of 11 years with the storage of 20 tonnes of potato. With the usage of the proposed system, the amount of CO2 production decreases by up to 53% compared to a system of absorption chiller working with natural gas.