The present invention proposes for this purpose an energy storage device using phase change material comprising an enclosure and a phase change material intended to be contained in said enclosure and a thermal heat source comprising a heat transfer fluid. . The present invention proposes for this purpose an energy storage device using phase change material comprising an enclosure and a phase change material intended to be contained in said enclosure and a thermal heat source comprising a heat transfer fluid. . rage capacity at nearly constant temperature. Some of the sensible TES systems, such as, thermocline packed-bed systems have higher energy densities than low gr ble source of energy, among other advantages. This device is a spherical encapsulated paraffin phase change heat exchanger device (stainless. . Thermal energy storage using phase change materials (PCMs) is one of the most attracting means of energy saving. Therefore there are many scientists working to generate more efficient materials.