Energy and economic analysis of a solar-assisted multi-commodity cold storage

Most of the existing cold storages of the developing countries are dedicated toward storage of a single commodity due to which they remain underutilized for a considerable part of a year. In this paper, a conceptual design of multi-commodity cold storage has been discussed to store three high-value perishable commodities for different periods of a calendar year for round the year utilization of the cold storage facility. A cooling system based on the lithium bromide-water absorption system has been designed to maintain a favorable inside microclimate. A solar thermal-photovoltaic-based hybrid power system has been designed to meet the thermal and electrical loads of the system. The performance of the cold storage system has been analyzed using a thermal model for a complete calendar year for the climatic condition of Kolkata, India. A life-cycle cost analysis of the power system has also been carried out. The study revealed that the product load contributes toward 70% of the cooling load during the months of product loading. It is also observed that forty-six numbers of parabolic trough collectors along with two hundred seventy-five numbers of SPV modules of 150 Wp each can meet the major fraction of the load on an annual basis. The economic analysis revealed that the payback period of the integrated power system is only 6.22 years. The study thus reinforces the viability of solar-powered multi-commodity cold storages for the developing countries of the world both from the technical and economic point of view.