Evaporative coolers provide a cooling effect by natural evaporation, in the process increasing relative humidity. Fans and air movers increase cooling through air circulation. Evaporative air conditioners do not have a compressor or condenser. Instead, liquid water or ice is poured into a tank and air movement releases this as vapour. Because they do not have a refrigeration circuit, they do not need hoses or pipes, allowing them to be truly portable. These units add humidity and are not suitable for computer, IT or server room applications. In moderate humidity locations there are many cost-effective uses for evaporative cooling, in addition to their widespread use in dry climates. For example, industrial plants, commercial kitchens, laundries, dry cleaners, greenhouses, spot cooling (loading docks, warehouses, factories, construction sites, athletic events, workshops, garages, and kennels) and confinement farming (poultry and dairy) all often employ evaporative cooling
