A device (1) for storage and conveyance of thermal energy for an energy production system, which device (1) is apt to receive the solar radiation and is based on the use of a modular fluidizable granular bed and a heat exchanger associated thereto. The modular fluidization allows the selective storage of heat or thermal transfer to the exchanger. At the basis of such use, there are the favorable features of thermal exchange of the fluidized beds and the effective convective conveyance of the heat subsequent to the mobility of the granular phase. Both these features are linked to the possibility of imparting a rheological behavior to a granular solid that is comparable to that of a fluid, actually thanks to the fluidization thereof. Such device mainly comprises: - a containment casing (2) provided with one or more cavities receiving the solar radiation (20); - a fluidizable bed of granular particles (3) suitable for thermal energy storage and conveyance, arranged inside the containment casing (2); - one feed inlet for feeding a fluidization gas through the bed (3) of particles by a suitable distributor (21); - a heat exchanger (4) immersed in the fluidizable granular bed and crossed by a working fluid; and - a feeding inlet for a fuel gas (401) as additional thermal input to increase the system management flexibility.