A system for dispensing a coolant for a thermal energy storage device including a stratified thermal storage tank for coolant, for injecting and/or withdrawing a coolant within a thermal storage tank, characterised in that it includes: - a support for dispensing coolant, for extending inside the thermal energy storage tank and able to enable the coolant to be injected and/or withdrawn within the thermal storage tank, - at least two thermostatic systems (3a-3f), secured to said dispensing support and spaced apart along said dispensing support so as to be located at thermal strata of the thermal storage tank having different temperatures, each thermostatic system (3a-3f) including at least one first thermostat and a second thermostat, the first thermostat being secured to said dispensing support so as to be in contact with the coolant of the thermal stratum where the thermostatic system (3a-3f) is located and the second thermostat being secured to said dispensing support so as to be in contact with the coolant to be dispensed by the dispensing support, the first thermostat and the second thermostat of each thermostatic system (3a-3f) passively driving at least one hydraulic system (5, 5a, 5b) of the dispensing system as a function of the comparison of the coolant temperature of the thermal stratum where the first thermostat is located and of the temperature of the coolant to be dispensed by the dispensing support to enable coolant to be dispensed within a target thermal stratum of the thermal storage tank with a temperature substantially equal to the temperature of the coolant for being dispensed, said at least one hydraulic system (5, 5a, 5b) including a first rod-shaped element secured to the first thermostat and a second rod-shaped element secured to the second thermostat, the first and second rod-shaped elements being able to move as a function of the temperature respectively applied to the first and second thermostats under the effect of the expansion of an expansion material of the first and second thermostats, the first thermostat and the second thermostat of each thermostatic system (3a-3f) being mechanically coupled to each other, the hydraulic system including a first dispensing movable element comprising a first portion on which the first and second rod-shaped elements exert a pressure on either side of said first portion and a second portion able to enable the coolant to be dispensed at the target thermal stratum or to be held within the dispensing support, the dispensing support including a side opening and a central wall, extending from this side opening towards the second portion of the dispensing movable element, at each thermal stratum of the thermal storage tank, the central wall delimiting on either side a first pass-through space inside the dispensing support and a second pass-through space opening into the thermal stratum considered through the side opening, the second portion of the dispensing movable element being able to close the first pass-through space or the second pass-through space as a function of the movement of the first and second rod-shaped elements. - a support for dispensing coolant, for extending inside the thermal energy storage tank and able to enable the coolant to be injected and/or withdrawn within the thermal storage tank, - at least two thermostatic systems (3a-3f), secured to said dispensing support and spaced apart along said dispensing support so as to be located at thermal strata of the thermal storage tank having different temperatures,