Technology is provided for a server facility cooling system. The system can include a coolant tank containing an electrically insulating liquid and one or more servers submerged in the liquid. At least a portion of the heat generated by the servers is transferred to the liquid. An elongate cooling loop extends vertically between a first end and a second end, wherein the first end is located in the air and the second end is located underground. A heat exchanger is positioned between the coolant tank and the cooling loop to transfer heat from the liquid to the cooling loop. A cylindrical cooling tower is positioned around the first end of the cooling loop.