There are lots of good reasons to consider buying a portable air conditioner. It is budget-friendly, maneuverable, and requires no wall-mounting at all.
The application of this product is very diverse: for living rooms, garages, and any areas from small to large. And, depending on each buyer’s needs, it can be professionally made to be quieter during operation or cool faster.
We have the six most efficient portable air conditioners on today’s list that are going to be focused on those exact categories. Take a look!
Here are the most efficient portable air conditioners you can buy in 2025:
- Best For Garages: SereneLife SLPAC8
- Best For Small Areas: Black + Decker BPACT08WT
- Quiet: TOSOT 8,000 BTU Portable Air Conditioner
- Fastest Cooling: Whynter Elite ARC-122DS
- Best For Living Rooms: COSTWAY 10000 BTU Portable Air Conditioner
- Best For Large Areas: Airo Comfort Portable Air Conditioner
| 6 Most Efficient Portable Air Conditioners | ||
|---|---|---|
Best For Garages | SereneLife SLPAC8 | |
Best For Small Areas | Black + Decker BPACT08WT | |
Quiet | TOSOT 8,000 BTU Portable Air Conditioner | |
Fastest Cooling | Whynter Elite ARC-122DS | |
Best For Living Rooms | COSTWAY 10000 BTU Portable Air Conditioner | |
Best For Large Areas | Airo Comfort Portable Air Conditioner | |
Best For Garages: SereneLife SLPAC8
- Perfect for small garages – deliver 8000BTU cooling power
- Reduce humidity levels – the Dehumidifier mode
- Easy to customize the product’s settings – includes a remote controller
- A bit loud while operating
SereneLife SLPAC8 is a great portable air conditioner for small garages. With 8000BTU cooling power, it can cool down a 225-square-foot space quickly.
There are three running modes to consider: Fan, Dehumidifier, and Cooling. Therein, the second set might come in handy for the garage because it helps reduce humidity levels to help soothe allergic symptoms to mildew and dust mites.
Including in the package is a remote controller where you can easily track and customize various features, such as fan speed, temperature, timer, mode, and power settings.
| SereneLife SLPAC8 Specifications | |
|---|---|
Dimension | 14.6 x 13.8 x 27.2 inches |
BTUs | 8,000 BTU |
Room Size | Up to 225 Sq. ft |
Highlight Features | deliver 8000BTU cooling power the Dehumidifier mode include a remote controller |
For small garages of under 225 square feet in size, we find the SereneLife SLPAC8 is the best to-go
Best For Small Areas: Black + Decker BPACT08WT
- Ideal for small rooms of up to 150 square feet – the 5000BTU cooling power
- Run quietly – the noise level range of 51 to 53 decibels
- Easy to install, use, and maintain - Self-evaporating operation, reusable air filter, and remote control function
- The duct/hose is extremely short
- The remote needs more improvement
Some buyers just need a portable air conditioner for their small living room, bedroom, office, or dorm. For them, we highly recommend the Black + Decker BPACT08WT.
It is a 3-in-1 air conditioner, with dehumidifying, fan, and cool modes, for various ventilation and cooling needs. The maximum cooling power it can offer is 5000BTU, which is capable of decreasing the heat in a room down to 65 degrees F.
And, the ideal room size of this portable AC is around 150 square feet.
With such a modest size, it also gives many other big advantages, such as quieter operation, quick assembly process, and low-maintenance.
| Black + Decker BPACT08WT Specifications | |
|---|---|
Dimension | 16.5 x 11.5 x 26 inches |
BTUs | 8,000 BTU |
Room Size | up to 150 sq. ft. |
Highlight Features | the 5000BTU cooling power the noise level range of 51 to 53 decibels The self-evaporating operation, reusable air filter, and remote control function |
Designed to be the most compact air conditioner with the smallest in size, the Black + Decker BPACT08WT is a potential candidate for small spaces
Quiet: TOSOT 8,000 BTU Portable Air Conditioner
- Incredibly quiet operation – the X-Fan technology
- Offer drier air for less dust mite allergy symptoms - Able to remove 2.3 pints of humidity per hour off the air
- Easy assembly – the detailed instructions & the versatile sliding windows
- The screws are a bit hard to screw in
The TOSOT 8,000 BTU Portable Air Conditioner intensively impressed us with its incredible quietness during operation.
While most other counterparts at the same cooling power create 51 to 55db depending on a specific setting, the noise level of this one is only 49 decibels. That is a big thank you to the new X-Fan technology application.
Once activated, it remains the fan spinning at the slowest speed for whisper-quiet operation. TOSOT 8,000 BTU Portable Air Conditioner also features three settings. The dehumidifier, therein, can remove up to 2.3 pints of humidity per hour.
| TOSOT 8,000 BTU Portable Air Conditioner Specifications | |
|---|---|
Dimension | 11.8 x 15.4 x 30.4 inches |
BTUs | 8,000 BTU |
Room Size | 300 Square Feet |
Highlight Features | the X-Fan technology Able to remove 2.3 pints of humidity per hour off the air the detailed instructions & the versatile sliding windows |
If you’re looking for an efficient portable air conditioner that also doesn’t disturb you from sleeping or working, then consider the TOSOT 8,000 BTU
Fastest Cooling: Whynter Elite ARC-122DS
- Cool down a 400-square-foot super-fast – offer 12,000BTU cooling power
- Automatically drain condensed water in most environments – the patented auto-drain function
- CFC-free and eco-friendly - the Green R-32 refrigerant
- When turning on the machine, the operation display only stays lit shortly
Providing 12,000BTU cooling power, Whynter Elite ARC-122DS offers cooling relief in almost any warm spots around your home. The most ideal room size to use this portable AC is around 400 square feet.
Under 40 minutes, it can cool down such that space to 61 degrees F, depending on the outside temperature. If changing to the Dehumidify mode, it is able to extract 76 pints of humidity during a 24-hour period.
Compared to other counterparts, it keeps the record of fastest cooling.
Another cool feature is the patented auto-drain function and it works in most environments. Besides, the Green R-32 refrigerant is CFC-free and eco-friendly.
| Whynter Elite ARC-122DS Specifications | |
|---|---|
Dimension | 17 x 29.5 x 16 inches |
BTUs | 12,000 BTU |
Room Size | up to 400 sq ft |
Highlight Features | offer 12,000BTU cooling power the patented auto-drain function the Green R-32 refrigerant |
We highly recommend the Whynter Elite ARC-122DS for those who are in need of efficient portable AC with the fast-cooling capability
Best For Living Rooms: COSTWAY 10000 BTU Portable Air Conditioner
- Suit medium to large living rooms - 10,000 BTU cooling power
- Easy maneuverability – four smooth-rolling casters
- Energy-efficient – a 24-hour programmable timer
- Not ideal for too hot areas (where the temperature reaches above 90 degrees F)
- The hose is a bit too big
COSTWAY 10000 BTU Portable Air Conditioner offers 10,000 BTU cooling power with three operating modes. Therein, you’ll get a big advantage from two fan speeds – high and low – for various cooling needs.
It is a wonderful option for medium to large spaces of up to 400 square feet, and at the highest mode, the noise level is acceptable – 52 decibels. Combining its elegant, stylish design, we highly suggest it for use in the living room.
Or, you can easily move it from room to room thanks to the smooth-rolling casters. In terms of functionality, it also gives you a remote and a 24-hour programmable timer.
| COSTWAY 10000 BTU Portable Air Conditioner Specifications | |
|---|---|
Dimension | 12 x 13.5 x 28 inches |
BTUs | 10000 BTU |
Room Size | Up to 400 Sq. Ft |
Highlight Features | 10,000 BTU cooling power four smooth-rolling casters a 24-hour programmable timer |
Due to the elegant design, quiet operation, and efficient cooling performance, the COSTWAY 10000 BTU Portable Air Conditioner is our proud choice for living rooms
Best For Large Areas: Airo Comfort Portable Air Conditioner
- Powerful – offer 14,000 BTU cooling power
- Deliver even air distribution - the automatic vertical swing design and horizontal window opening
- Convenient to use - clear LED display on the panel & a remote
- Durable and efficient – the removable and washable air filter
- No complaint
Airo Comfort Portable Air Conditioner is the most powerful model in our list, offering 14,000 BTU cooling power for a space of up to 600 square feet in size. But the air distribution is not too harsh or just focused on a certain spot.
Instead, it is evenly distributed throughout the room, all thanks to the automatic vertical swing design and horizontal window opening.
The machine is also easy to use. While there is a front panel with a clear LED display where you can easily track various features, it comes with a remote. The temperature, besides, is presented in both degrees C and degrees F for your convenience.
Last but not least, the air filter is removable and washable for longer use.
| Airo Comfort Portable Air Conditioner Specifications | |
|---|---|
Dimension | 17.8 x 15 x 30.5 inches |
BTUs | 14,000 BTU |
Room Size | 450-600 square feet |
Highlight Features | offer 14,000 BTU cooling power the automatic vertical swing design and horizontal window opening clear LED display on the panel & a remote the removable and washable air filter |
The Airo Comfort Portable Air Conditioner gives you the best of both worlds – a compact, portable design for space-saving and powerful cooling effects. For large areas of up to 600 square feet, it is the best bet
How To Choose The Most Efficient Portable Air Conditioner?
ERR (Energy Efficiency Rating)
There is a basic rule of thumb when it comes to EER – the higher the rating, the more money is saved.
In general, a portable air conditioner should be EER rated at least 8 and if it is above 10, that model is arguably energy-efficient.
BTUs Rating
BTU stands for British thermal unit.
This is how the capacity of a portable air conditioner is measured. To choose the most efficient model, you should pay close attention to this unit.
A portable air conditioner with a too weak BTU rating will consume more energy constantly to cool the room while a too-strong one will waste unnecessary power. At the current, there are two independent BTU rating systems:
- ASHRAE BTU rating: to measure the amount of BTUs of heat removed from the air per hour by a portable air conditioner
- SACC BTU rating: to measure the amount of heat sucked back into a home
- And, the SACC BTU rating is frequently smaller than the ASHRAE BTU rating, ranging from 50% to 60%. For example:
- 3,000 SACC = 6,000 ASHRAE
- 4,500 SACC = 8,000 ASHRAE
- 6,000 SACC = 10,000 ASHRAE
While not many manufacturers list both of these ratings on their product description, if you see only one BTU rating, it means the ASHRAE rating.
Size
To choose the right size of a portable air conditioner, first off, determine your room size.
And, there’s one important thing you should remember: Unlike with central ACs that you should go the true size of the unit for the highest efficiency, it is better to size up when choosing a portable free-standing AC.
For example:
ASHRAE rating (BTUs) | Room Size (square feet) |
14,000 | 350-450 |
12,000 | 300-400 |
10,000 | 250-350 |
9,000 | 200-300 |
8,000 | 150-250 |
6,000 | 100-200 |
But if your case has one or more than these issues, it is better to pick a portable air conditioner with 1000BTUs larger than what’s recommended in the chart:
The unit is going to be used in your kitchen (it’s because cooking increases humidity and heat in the room)
- There are usually three or more people in the room
- The room face west or south with no shadow of trees
- The ceiling is higher than 8’
Which Brands Make The Most Efficient Portable Air Conditioner?
Black + Decker
Originally established in 1910, Black+Decker has been one of the world’s biggest American manufacturers dedicated to home appliances, home improvement products, and more.
TOSOT
This is actually a brand specializing in HVAC equipment manufactured by GREE Electric Appliances Company of Zhuhai (Est. 1991) - the largest residential air conditioner manufacturer.
FAQs
How efficient are portable air conditioners?
An energy-efficient portable air conditioner can save up to $70/year, and it is measured by ERR rating – the ratio between electrical power (in watt) and useful cooling effect (in BTU).
Can I use a portable air conditioner in a room without a window?
Yes, you can. In a room with no windows, there are two ways to vent your portable AC – either through a wall/a drop-ceiling or through a dryer.
What happens if you don't vent portable air conditioners?
If that happens, hot air will keep locked up inside your room, which neutralizes the cooling effect of the machine.
Can you run a portable air conditioner all day?
Technically yes, you can. But it might not be a good choice in reality because your portable AC can cause a short if it doesn’t have a dedicated plug.
Do you have to empty water from a portable air conditioner?
No, you don’t (in most cases). The reason is most portable ACs these days are built with self-draining or a condensation exhaust system to remove excess water.
Conclusion
Do you find our ultimate guide helpful? Have you found out the most efficient portable air conditioner for your needs? Kindly share your thoughts with us, we really love to hear. Finally, thanks for reading!
