If central air conditioning is not cost-effective or needs to be supplemented, two options you may consider are portable AC systems or a window-mounted unit. Here’s how they compare:
The Initial cost
Up-front, portable AC units tend to be slightly more expensive than window units of the same capacity. On average, you may expect to pay about $100 more. However, when considering cost, don’t forget the value of convenience—having an AC system that can be moved where you need it.
The Cost of Utilities
Monthly utility costs for a portable AC unit and window-mounted unit of comparable size should be about the same. To minimize energy consumption, make sure any AC system you get has a good Energy Efficiency Rating (EER).
Portable AC systems and window-mounted units both measure cooling capacity in BTUs, and you can find comparable units. So, both types of AC systems have the potential to provide the cooling capacity you need; what’s important is to find the right size/BTU potential for the size of room and number of people occupying the room you want to cool.
Modern portable AC systems and window-mounted units are engineered for energy efficient performance. Their energy efficiency is a rated on a scale (EER) or indicated by an Energy Star Rating. Look for a unit with a rating of 9 or above for best energy efficient performance.
Just like any other cooling unit, portable air conditioners and window-mounted units can last for a long time if maintained properly. Most systems provide a useful life of five to ten years.
AC maintenance is where portable systems really shine over window-mounted units. Because they are easy to move, portable AC systems make it easy to reach components that needs cleaning or changing, like condenser coils and air filters, respectively.
Overall, a portable AC system or a window-mounted AC unit can provide energy efficient cooling you need to maintain a comfortable indoor climate. The big question is whether or not you are willing to invest a little more for the convenience of portability.