Drive system (100; 200; 300) based on cyclic conversion of thermal energy into mechanical or electrical energy by exploiting a temperature difference between at least two media (M1, M2) and the contraction of a metal element with shape memory properties, comprising: - at least one drive assembly (48, 48'; 49) comprising a housing (34; 34') with at least one metal element placed within the housing , - at least one restoring element located inside the housing (34; 34'), - at least one movable actuating element to which the metal element and the restoring element are coupled, - wherein a gaseous or liquid medium flows around the metal element and the restoring element , characterised in that - the drive assembly (48, 48'; 49) comprises at least one first store containing a first gaseous or liquid medium (M1) and at least one second store (11; 12) containing a second gaseous or liquid medium (M2), wherein the first and second media are of different temperature, wherein the second store has a passage opening for direct connection of the second store to a cylinder chamber through a bottom of the housing , - the housing is a cylinder which contains a cylinder piston arranged in a liquid- and gas-tight manner and wherein the cylinder piston forms the actuating element , - the cylinder piston divides the cylinder into two separate cylinder chambers , of which the one, first cylinder chamber bounded by the base contains the metal element with shape memory properties and the other, second cylinder chamber contains the restoring element , - wherein the metal element is anchored at an attachment point (A) to the cylinder piston and at an attachment point (B) located within the second store such that a portion of the metal element is in contact with the second gaseous or liquid medium (M2) of the second store and a portion is in contact with the second gaseous or liquid medium (M1) in the first cylinder chamber . - at least one drive assembly (48, 48'; 49) comprising a housing (34; 34') with at least one metal element placed within the housing , - at least one restoring element located inside the housing (34; 34'), - at least one movable actuating element to which the metal element and the restoring element are coupled, - wherein a gaseous or liquid medium flows around the metal element and the restoring element , characterised in that - the drive assembly (48, 48'; 49) comprises at least one first store containing a first gaseous or liquid medium (M1) and at least one second store (11; 12) containing a second gaseous or liquid medium (M2), wherein the first and second media are of different temperature, wherein the second store has a passage opening for direct connection of the second store to a cylinder chamber through a bottom of the housing , - the housing is a cylinder which contains a cylinder piston arranged in a liquid- and gas-tight manner and wherein the cylinder piston forms the actuating element , - the cylinder piston divides the cylinder into two separate cylinder chambers , of which the one, first cylinder chamber bounded by the base contains the metal element with shape memory properties and the other, second cylinder chamber contains the restoring element , - wherein the metal element is anchored at an attachment point (A) to the cylinder piston and at an attachment point (B) located within the second store such that a portion of the metal element is in contact with the second gaseous or liquid medium (M2) of the second store and a portion is in contact with the second gaseous or liquid medium (M1) in the first cylinder chamber . <EOS>