An apparatus for the accumulation and transfer of thermal energy is disclosed including a thermal energy charging device having a bed of fluidizable solid particles received within a casing and acting as heat accumulation means by being exposed to a thermal energy source, heat exchange means operating in counter-current, configured for an exchange of thermal energy between a heated vector mass of the bed particles and an operative fluid, transport means configured for feeding the vector mass of the bed particles from the device to the heat exchange means and for returning part of the vector mass, downstream the heat exchange means, to the device, and a control unit associated with parameter detecting means arranged selected locations of the apparatus to control the flow of the vector mass within the apparatus.