What is the cooling medium used in a cooling tower?

The cooling medium used in a cooling tower is most commonly water. Water acts as an efficient medium for heat exchange, absorbing heat from the fluid that needs to be cooled and then being evaporated in the cooling tower, thereby transferring the heat to the atmosphere. This process is crucial for maintaining system temperatures, particularly in industrial and HVAC applications.

While air is involved in the process as it helps to facilitate the evaporation of water, it is not the primary cooling medium. Refrigerants and oil are used in different types of cooling systems but are not suited for use in traditional cooling towers. Refrigerants operate within closed systems such as air conditioning units, and oil might be used in certain specialized cooling systems but not typically for cooling towers. Therefore, the role of water as the cooling medium makes it the most relevant and accurate choice in this context.