The achievement of European climate energy objectives which are contained in the European Union's (EU) “20–20–20″ targets and in the European Commission's (EC) Energy Roadmap 2050 is possible, among other things, through the use of energy storage technologies. The use of thermal energy storage (TES) in the energy system allows to conserving energy, increase the overall efficiency of the systems by eliminating differences between su. The achievement of European climate energy objectives which are contained in the European Union's (EU) “20–20–20″ targets and in the European Commission's (EC) Energy Roadmap 2050 is possible, among other things, through the use of energy storage technologies. The use of thermal energy storage (TES) in the energy system allows to conserving energy, increase the overall efficiency of the systems by eliminating differences between supply and demand for energy.The article presents different methods of thermal energy storage including sensible heat storage, latent heat storage and thermochemical energy storage, focusing mainly on phase change materials (PCMs) as a form of suitable solution for energy utilisation to fill the gap between demand and supply to improve the energy efficiency of a system. PCMs allow the storage of latent thermal energy during phase change at almost stable temperature. The article presents a classification of PCMs according to their chemical nature as organic, inorganic and eutectic and by the phase transition with their advantages and disadvantages. In addition, different methods of improving the effectiveness of the PCM materials such as employing cascaded latent heat thermal energy storage system, encapsulation of PCMs and shape-stabilisation are presented in the paper. Furthermore, the use of PCM materials in buildings, power gener. ••Different methods of thermal energy storage have been investigated.••Phase change materials investigated as a suitable solution for energy storage.••Phase change materials allow latent thermal energy storage at stable temperature.••Different methods of improving the effectiveness of the PCM materials were studied.••The use of PCM materials in different sectors was presented.Phase change materialsThermal energy storageLatent heat storageThermochemical energy storageClassification of PCMsPCM applicationsAA-CAES advanced adiabatic compressed air energy storageANN artificial neural networkCFD computational fluid dynamicsCLHTES cascaded latent heat thermal energy storageCSP concentrating solar powerCTES The European Union's policy objective is to move towards a low-carbon economy, with at least a 40% reduction in greenhouse gas emissions by 2030. This is due to the fact that heating and cooling of buildings consume almost half of the EU's energy. In addition, significant amount of thermal energy is a by-product of other energy applications are usually not collected and not used efficiently. The achievement of Europe's climate energy targets, which are included in the European Union (EU) 20–20–20 targets and the European Commission (EC) Energy Roadmap 2050, is made possible by using energy storage technology which provides flexibility and supports the integration of renewable energy into the energy system.The storage of thermal energy is possible by changing the temperature of the storage medium by heating or cooling it. This allows the stored energy to be used at a later stage for various purposes (heating and cooling, waste heat recovery or power generation) in both buildings and industrial processes. The use of Thermal Energy Storage (TES) in the energy system allows to conserving energy, increase the overall efficiency of the systems by eliminating differences between supply and demand for energy, reduce investment and running costs as well as to reduce carbon dioxide (CO2) emissions and other environmental pollutants. In addition, the use of renewable, low-carbon ene.
