Combination of a system (2, 42) for providing temperature-controlled water in an aircraft and an aircraft trolley, wherein the system (2, 42) for providing temperature-controlled water in an aircraft comprises: - at least one tank (4, 6, 44), - at least one water temperature-controlling unit (8, 10, 46), - a control unit, and - a power supply terminal, wherein the at least one water temperature-controlling unit (8, 10, 46) can be coupled to the at least one tank (4, 6, 44) in order to heat or to cool water situated therein, wherein the control unit is connected to the at least one water temperature-controlling unit (8, 10, 46) in order to activate the at least one water temperature-controlling unit (8, 10, 46) for controlling the temperature of water in the at least one tank (4, 6, 44) to a predefined temperature, wherein the power supply terminal can be connected to an on-board voltage source in order for the at least one water temperature-controlling unit (8, 10, 46) and the control unit to be supplied with electrical voltage, wherein the system (2, 42) is in the form of a coherent and self-contained unit which can be integrated into a parking place for a half-size or full-size trolley in a galley of the aircraft, and wherein the at least one tank (4, 6, 44) is mounted so as to be exchangeable to take the at least one tank out (4, 6, 44) of the system and readily insert it into the trolley, or wherein the system (2, 42) has a water discharge connection which is coupled to the at least one tank (4, 6, 44) and wherein the water discharge connection is configured to be connected to the trolley in order for water to be discharged from the at least one tank (4, 6) of the system (2, 42) and for the water to be received by the trolley. trolley, wherein the system (2, 42) for providing temperature-controlled water in an aircraft comprises: - at least one tank (4, 6, 44), - at least one water temperature-controlling unit (8, 10, 46), - a control unit, and - a power supply terminal, wherein the at least one water temperature-controlling unit (8, 10, 46) can be coupled to the at least one tank (4, 6, 44) in order to heat or to cool water situated therein, wherein the control unit is connected to the at least one water temperature-controlling unit (8, 10, 46) in order to activate the at least one water temperature-controlling unit (8, 10, 46) for controlling the temperature of water in the at least one tank (4, 6, 44) to a predefined temperature, wherein the power supply terminal can be connected to an on-board voltage source in order for the at least one water temperature-controlling unit (8, 10, 46) and the control unit to be supplied with electrical voltage, wherein the system (2, 42) is in the form of a coherent and self-contained unit which can be integrated into a parking place for a half-size or full-size trolley in a galley of the aircraft, and - at least one tank (4, 6, 44), - at least one water temperature-controlling unit (8, 10, 46), - a control unit, and - a power supply terminal, wherein the at least one water temperature-controlling unit (8, 10, 46) can be coupled to the at least one tank (4, 6, 44) in order to heat or to cool water situated therein, wherein the control unit is connected to the at least one water temperature-controlling unit (8, 10, 46) in order to activate the at least one water temperature-controlling unit (8, 10, 46) for controlling the temperature of water in the at least one tank (4, 6, 44) to a predefined temperature, wherein the power supply terminal can be connected to an on-board voltage source in order for the at least one water temperature-controlling unit (8, 10, 46) and the control unit to be supplied with electrical voltage, wherein the system (2, 42) is in the form of a coherent and self-contained unit which can be integrated into a parking place for a half-size or full-size trolley in a galley of the aircraft, and wherein the at least one water temperature-controlling unit (8, 10, 46) can be coupled to the at least one tank (4, 6, 44) in order to heat or to cool water situated therein, wherein the control unit is connected to the at least one water temperature-controlling unit (8, 10, 46) in order to activate the at least one water temperature-controlling unit (8, 10, 46) for controlling the temperature of water in the at least one tank (4, 6, 44) to a predefined temperature, wherein the power supply terminal can be connected to an on-board voltage source in order for the at least one water temperature-controlling unit (8, 10, 46) and the control unit to be supplied with electrical voltage, wherein the system (2, 42) is in the form of a coherent and self-contained unit which can be integrated into a parking place for a half-size or full-size trolley in a galley of the aircraft, and wherein the at least one tank (4, 6, 44) is mounted so as to be exchangeable to take the at least one tank out (4, 6, 44) of the system and readily insert it into the trolley, or wherein the system (2, 42) has a water discharge connection which is coupled to the at least one tank (4, 6, 44) and wherein the water discharge connection is configured to be connected to the trolley in order for water to be discharged from the at least one tank (4, 6) of the system (2, 42) and for the water to be received by the trolley.