A device for storage and exchange of thermal energy of solar origin, which device is configured to receive a concentrated solar radiation using an optical system of “beam down” type, which device comprises:—a containment casing which defines an internal compartment and has an upper opening configured to allow entry of the concentrated solar radiation, which opening puts in direct communication the internal compartment with the external environment having no closure or screen means;—a bed of fluidizable solid particles, received within the internal compartment, which bed has an irradiated operative region directly exposed, in use, to the concentrated solar radiation that enters through said opening and a heat accumulation region adjacent to said operative region;—fluidization elements of the bed of particles, configured to feed fluidization air within the compartment, which fluidization means is configured to determine different fluid-dynamic regimens in the operative region and in the accumulation region, based upon different fluidization speeds, wherein, in use, the particles of the operative region absorb thermal energy from the solar radiation and they give it to the particles of the accumulation region.