Linked from
The 13 pages that link to Cooling tower, each with the reason it gives.
Evaporative coolingRelated: Evaporation carries heat away from water in many industrial systems.
CondenserRelated: It often cools the water that serves as a condenser's heat sink.
Waste heatRelated: Power plants and factories use towers to reject heat they cannot use.
Thermal power stationBroader topic: It rejects some of the cycle’s waste heat to the air.