Review on transportable phase change material in thermal energy storage systems

Historically a drawback of using PCMs as a storage medium has been the low rates of heat transfer. Heat transfer enhancement techniques studied have included the use of additional metallic material and increasing heat transfer surface area such as fins to improve heat transfer rates of the PCM. Although these techniques are effective, they add significant cost and reduce the compactness factor of the thermal energy storage system. Recent research has been conducted on heat transfer enhancement that makes use of moving or transporting the PCM. This method is not only effective for increasing the heat transfer; it is less expensive and maintains a high compactness factor for the thermal energy storage system. This review paper presents the different heat transfer enhancement techniques reported in the literature. It also summarises the research conducted on phase change storage systems where the PCM is moved in the storage system.