Latent heat PCM for use in low temperature refrigeration during load shedding

In South Africa, it is evident that electricity demand outweighs the supply, and it has caused power failure in recent years. When the electrical grid is overly strained, Eskom implements loadshedding to prevent system failure. Food preservation is compromised during load-shedding which results in food spoilage as refrigeration systems relies on electricity to power the compressor. Alternative approaches to preserve food products is required and it can be achieved by utilising energy storage material such a latent heat phase change material (PCM). The use of PCM in refrigeration is gaining industrial interest due to the load shifting potential offered by latent heat PCM which assists in minimising the electricity bill. PCM application in refrigeration can reduce the compressor’s cycling period while minimising energy consumption. Therefore, thermal characterisation of a eutectic PCM was done in a Differential Scanning Calorimeter (DSC). The latent heat and phase change temperature values were determined at different sample mass. A saltwater solution with a mass ratio of 20:80 was used as a PCM. The thermal properties on the solution were evaluated with a DSC. The PCM has a latent heat and melting temperature of 260 kJ/kg and -21 ᵒC respectively. This PCM has a high latent heat storage capacity and can be used to maintain the temperature of food products during power failure (loadshedding).