Mobility is the key advantage, and ease of use is a close second. Just roll it in to the desired area, install the exhaust hose and lead it out a window or opening and plug it in. Bingo, you have a nice cool room.
Unfortunately at this time, a portable air conditioner no exhaust system does not yet exist. The heat produced from the air conditioner itself running, has to be vented somewhere other than inside the room. The whole purpose would be defeated otherwise.
Portable ac units are great for small apartments, which may have windows that cannot sustain a window installed unit. The windows may be too small, or the wood may be rotted etc. Just roll in the portable unit, plug it in and let it do the work.
These units use a compressor and freon , just as normal air conditioning systems, to cool the room’s temperature. They are perfect for senior citizens who may live alone, and can roll it from room to room with them. It must however, be emptied of water every now and then similar to a dehumidifier. As it cools the air, it also extracts heat and moisture, making the exhaust hose and emptying of water necessary every now and then.
They are also great for special events, where food or liquids must be temporarily stored, in a cool place. Although a portable ac unit is not meant to take the place of a complete air conditioning system, it is a great tool for cooling down certain rooms for short periods of time.
When buying a system, you must look at your needs, and see if a portable system is right for you. Maybe your apartment or house is too large, maybe you cannot empty the water for physical reasons, maybe the cost will be too high or just right. Sometimes a portable unit is perfect, other times it may not be the right choice. Examine and weigh all the factors first.