How does evaporative cooling function?

Evaporative cooling operates on the principle of water evaporation, where heat is absorbed from the surrounding air as water changes from a liquid to a vapor. This process lowers the air temperature effectively, creating a cooling effect. In applications like swamp coolers or evaporative coolers, outdoor air is drawn through water-saturated pads. As the air passes through these pads, it loses heat to the evaporating water, resulting in cooler, more humid air entering a space. This method is energy-efficient and particularly suitable for dry climates, where the relative humidity is low, allowing for more effective evaporation and cooling.

Other options do not describe the working of evaporative cooling accurately. Mechanically chilled air refers to air that has been cooled through refrigeration processes, which is not the case in evaporative cooling. Compressing refrigerant is a process used in conventional air conditioning systems, while heating the air contradicts the cooling effect that is sought in evaporative cooling.