The air conditioner uses refrigerants to remove heat and moisture from inside a space. AC uses a fan to distribute the conditioned air to both improve thermal comfort and indoor air quality. Air cooler air is cooled in coils by chemical means and removes heat and moisture is dissipated outdoor. A portable evaporative cooler requires fewer materials to operate i.e only water & electricity. They are also having low maintenance than air conditioners. Since coolers use water to cool naturally they do not produce any mist or fog. They provide relief from the heat in any climate due to advancements in evaporative cooling technology. So according to me, evaporative cooling is always better than air conditioning.