Portable air conditioning comes from freestanding units that move from room to room as needed, providing cool air in homes that do not have standard air conditioning. Some units also act as dehumidifiers to remove moisture from the air.
The size of portable air conditioner needed depends on the size and use of the room. A 200-square-foot room needs an 8,000 BTU unit, and a 600-square-foot room requires a 14,000 BTU unit. Home Depot recommends upgrading by 600 BTUs if the unit is used in a room that typically has more than two people in it. Portable units used in kitchens need 4,000 BTUs more than regular rooms of the same size.