Hydraulic elevator drive system and elevator system comprising a hydraulic elevator drive system

Hydraulic drive system (14) for driving an elevator system (2), the hydraulic drive system (14) comprising:

• a fluid tank (20) for storing a hydraulic fluid (25);
• a hydraulic fluid supply conduit (22) that is configured for being fluidly coupled to a hydraulic cylinder (12a) of the elevator system (2);
• a fluid pump (26) that is configured for pumping hydraulic fluid (25) from the fluid tank (20) into the hydraulic fluid supply conduit (22);
• an electric power supply circuit (30) comprising at least one electric power storage device (34, 36) and configured for receiving single phase alternating current for charging the at least one electric power storage device (34, 36) and for selectively supplying electric power from the at least one electric power storage device (34, 36) to drive the fluid pump (26);
• a hydraulic fluid return conduit (24) that is configured for being fluidly coupled to the hydraulic cylinder (12a) for returning hydraulic fluid (25) from the hydraulic cylinder (12a) into the fluid tank (20);
• and
• an electric generator (52) that is configured for generating electric power from hydraulic fluid (25) flowing through the hydraulic fluid return conduit (24) and for supplying the generated electric power to the electric power supply circuit (30).