Photovoltaic thermoelectric cooling system for off-grid vaccine refrigerator: an experimental study

The rapidly rising demand for refrigeration technologies, mainly in refrigeration and air conditioning, medical applications, and electronic component cooling, produced much more energy than required. Thermoelectric refrigeration is an innovative way to use additional energy to cool and reserve cooling. In this research, a photovoltaic-thermoelectric refrigeration system capable of sustaining vaccine storage within the limit of 2-8 degrees C has been established by experimentally optimizing its volume and performance. The design specification is to cool the volume using forced convection to the desired temperature range in less than 30 min and sustain retained heat for at least the next hour. The experimental research is divided into two stages: the first determines the optimal volume of vaccine storage under different testing conditions using only grid power, and the second analyses storage performance using solar energy through photo voltaic (PV) integration. The solar direct drive and the solar drive with battery support have been timed, revealing a holding period of 4 h, 46 min and 5 h, 29 min, respectively. The refrigerator's design criteria, prospective characteristics, and final design are all thoroughly highlighted. Finally, we conclude that this research will likely benefit the modeling and analysis of thermoelectric cooling systems.