Development of an Advanced Solar-hybrid Adsorption Cooling System for Decentralized Storage of Agricultural Products in India.

Agricultural products play a significant role and could yield substantial amount of foreign exchange for a tropical country like India. However, in India 30% of the agricultural products are spoiled in storage and transit. In this present investigation, funded by EC (DGXII), TERI (Tata Energy Research Institute) and DLR (German Aerospace Establishment) have jointly designed and tested a solar-hybrid methanol/silicagel based adsorption cooling system for its possible application for decentralised cold storage of agricultural products in India where electricity is either not available or not reliable. A 10 kW (2.9 TR) system (for 100 t of agro-products, 240 mPP in volume) has been designed and preliminary testing has been completed successfully. Methanol/silica gel working pair has been used in the adsorption refrigeration unit. It is operating with a very low (75-80 °C) generation outlet temperature and rejecting heat at near ambient. This 10 kWBthB capacity cooling unit has offered cooling with a coefficient of performance (COP) for cooling of 0.3 to maintain a cold storage at 1 to 3°C and cooling density of 100 W/kg silicagel at an evaporator temperature of 0°C. The system is designed as a stand alone solar and waste heat driven cold storage with a dual-fuel engine, which generates 5 kWBeB electricity side by side. It has been estimated that the pay back period of such a system will be about 5 years with a 3050% increment in electricity purchase rate of Indian State Electricity Board.