The issue with swamp coolers (evaporative cooling) is that you need relatively low humidity for them to work and they increase the humidity of the interior cool

The issue with swamp coolers (evaporative cooling) is that you need relatively low humidity for them to work and they increase the humidity of the interior cooled environment. If you use them in combination with an air conditioner, they will very likely reduce the efficiency of the air conditioner by increasing the dehumidification load of the air conditioner.