Design of a photovoltaic system using thermoelectric Peltier cooling for vaccines refrigeration

The refrigeration of thermolabile medicines and vaccines require the continuous provision of electrical energy so that their therapeutic efficacy is not affected. This represents an important problem for rural zones where there is no accessible electrical energy. In this work, we design a photovoltaic energy system for refrigeration of thermolabile medicines to be used in rural towns without electrical energy available. The system uses a thermoelectric refrigerator based on the Peltier effect, which produces a temperature difference when electrical power is provided to it. It will be shown that for a typical application for vaccine refrigeration, the required module is about 92 W peak connected to batteries with a storage capacity of 212 Ah. The designed refrigeration system should store 5 l of vaccines at temperatures in the range between 4 °C and 6 °C using a Peltier cell (TEC) that consumes 37 W at 12 V.