Simulation and Experimental Performance Analysis of Portable Locally-Made Solar-Powered Cooler for Vaccine Storage

Poor storage conditions, particularly exposure to extreme temperatures, can significantly compromise vaccine efficacy, making them ineffective or harmful. This highlights the urgent need for adequate storage infrastructure and monitoring systems, especially in remote areas with limited healthcare resources. This study evaluates the performance of a locally-made solar-powered cooler designed for vaccine storage in such environments. A digital AKO thermostat was integrated to control the compressor according to specified temperature limits, alongside a data logger for continuous temperature monitoring and a fluke device for DC and voltage measurements. The experimental results, validated against existing literature, were reliable and accurate. Key findings reveal that the cooler can reduce temperature to -14.9°C within 180 minutes, surpassing the performance of previous models that attained a temperature of -10°C after 144 minutes. The optimal insulation thickness for maintaining a cooling temperature of -15°C was determined to be 0.07 m using polyurethane insulation material, compared to 0.129 m with Feather Fiber, reflecting a 45.7% increase in efficiency at an ambient temperature of 42°C. Similar results were observed at an ambient temperature of 32°C. Modeling outcomes provided valuable guidance for the experimental design and comparative analysis.