REVIEW ON LATENT HEAT STORAGE AND PROBLEMS ASSOCIATED WITH PHASE CHANGE MATERIALS

Energy storage devices have important role in the energy system as they minimize the mismatch between the supply and demand.This leads to improvement of the performance and the reliability of the systems.In thermal energy storage systems the Latent heat type thermal energy storages (LHTES) are attractive since they have high energy storage density and nearly isothermal operation at the phase transition temperature of the material usedthat is commonly known as phase change material (PCM).In this paper PCMs with solid-solid and solid-liquid phase transition are discussed.Though PCMs with solid-solid phase transition seem attractive due to their less stringent containment requirements but they are not widely used because of their low latent heat.PCMs with solid-liquid phase transition are the most studied and used latent heat storage materials.Those are discussed in details with their selection criterion, classification and applications.The steps involved in development of the energy storage systems and problems associated with PCMs are discussed in the next part of the paper.This will give better understanding of the latent heat storage systems to the reader.