How much water is used in an evaporative cooling system and in an adiabatic cooling system?

In an evaporative system, approximately 2% of the mass to be cooled evaporates and is released back into the environment. Around 1% of the mass to be cooled is discharged to the drain in order to maintain the correct concentration of salts in the circuit. The exact value depends closely on the quality of the treated water.

In an adiabatic system, approximately 0.2% of the mass to be cooled evaporates and is released into the environment (typically during warm or hot periods, when a specific section is sprayed with water to reduce the temperature of the incoming air).