The project’s goal is to develop and demonstrate novel modular, compact, high performances and Plug&Play thermal energy storage (TES) solutions for heating, cooling and hot tap water production. The new concept of TES proposed in the project will provide electricity load shifting with meaningful peak shaving of the thermal and electric load demands. Furthermore, the exploitation of renewable sources will be a key point of the new TES device considering at the same time the cost-effective results in terms of energy, costs and sustainability of the system. The project will provide a TES system able to store energy for heating and cooling in building applications for a period of at least four weeks. The novel TES system will be based on a closed-loop TCM reactor insulated by PCM and equipped with an ice storage, again integrated with PCM, for high cooling energy demand. The thermodynamic cycle has been designed to benefit from a further PCM thermal buffer tank, breaking through the closed-loop concept by compensating the energy for humidification with its latent heat. An advanced heat pump will be finally dedicated to the power conversion during the thermal charging process of reactor and PCMs storages, increasing the overall performance. A dedicated control system will be developed to operate the TES according to the energy production and the end-users’ requirements, adapting to the conditions of use according to the type of air conditioning system and the particular demand for domestic hot water. The TES solution will be adaptable to all the different possible European scenarios, in terms of energy policy and end-users’ requirements. It will be designed to be used both as integrated into the building heating system and in the smart electricity grid, or in buildings not connected to district heating and cooling network. Different characteristics of the system will be taken into account, ranging from storage efficiency and durability to cost reduction and LCA and LCCA.