Design and Analysis of Portable Solar Powered Refrigerator Unit

Portable solar powered refrigerator unit today is important due to transmission of clinical samples to many broad areas. Some medical samples are kept in a cooler box for a short term for sampling by health staff. The drawback of the box is that it always needs a lot of ice cubes for active coolant until the ice melted. Places that have no access to electricity will damage the samples due to the box is not cool anymore. This study has designed a portable solar battery mini fridge that harnesses solar energy for cooling. It is flexible to the existing mini fridge and has enough capacity to supply the load for hours. The design consists of a solar panel to harvest the energy, a battery to keep the energy, a control panel to control its charging and discharging as well as protection measures. Arduino controller is embedded as the control designed system to the temperature sensor, current sensor, and LCD as input and output. Two tests had been carried out for compatibility of a solar system on the mini fridge which is battery charging to PV modules and load testing to the mini fridge. The result shows that the battery was able to supply for more than two hours since 14.29% of the battery is still available before the supply ends. The mini fridge was able to keep on cooling about 16 degrees after 2 hours. This research is significant for portable mini fridge design using a solar battery which lasted longer than 2-hour usage time for medical officers.