A power production system is provided that includes: a hydraulic turbine, installable in a penstock and being rotatable in a first rotation direction by effect of a flow of fluid flowing in the penstock in a downward direction; an energy converter group; an accumulator; a control unit, configured to operate the system in a power generation mode, in which the energy converter group receives an input mechanical power from the hydraulic turbine rotating in the first rotation direction, generates an output electric power and supplies said output electrical power to an external grid and/or to the accumulator, and in a downward pushing mode, in which the energy converter group absorbs an input electrical power from the accumulator and generates an output mechanical power to move the hydraulic turbine.