Optimum sizing of PV panel, battery capacity and insulation thickness for a photovoltaic operated domestic refrigerator

In India, there are several places where the electrical power is not continuously available therefore vaccine preservation is not possible and people are losing their lives. Solar energy based refrigerators may overcome the issue. The electricity generated through photovoltaic panels can be used to drive the refrigeration systems. In this paper, a parameter study is carried out to find out the best combination of the PV panel wattage, battery capacity and insulation level to operate the refrigerator stand-alone on solar power. The transient simulation software (TRNSYS) is used to simulate the PV based refrigeration system. The system consists of a refrigerator with 50 l capacity, 24 V battery bank, 1 kVA inverter, and PV panels with charge controller. The simulation model has been validated with experimental data. The parameters used are: wattage of PV panels in PV array, capacity of the battery bank and variation of insulation in refrigerator. The results conclude that it is feasible to operate a refrigerator (25 mm insulation thickness) on SPV without grid power with 320 W panel arrays with 50 Ah battery capacity. As the thickness of insulation is increased to 50 mm then 200 W panel capacity is sufficient to drive the refrigerator.