7 Most Energy Efficient Portable Air Conditioners 2022

Air conditioners make our lives easier and more comfortable, whether at home or in the workplace. When searching for the best portable air conditioner, it is essential to consider the features, size, and efficiency. 

Nowadays, homeowners are more concerned with the energy efficiency of portable cooling units, mainly due to the benefits that it offers. The more energy-efficient an AC is, the more money it helps you save.

What’s more, having the most energy efficient portable air conditioner also helps to become aware of how energy is used, when it’s wasted, and how it can be used more effectively and efficiently to keep your room cool.

So, the question is what are some of the best energy-saving portable air conditioners? The main objective of this post is to help you identify ideal air conditioners since we’ll be reviewing them in detail with their pros and cons.

Best Energy Efficient Portable Air Conditioners

1. Black + Decker BPACT08WT Portable Air Conditioner

BLACK+DECKER 8,000 BTU Portable Air Conditioner up...
  • Portable AC: Use this personal air conditioner (15.3” x 14” x 24.8”) in rooms up to 350 sq. ft. Stay cool in the hot summer months and sleep well with this BLACK+DECKER ac unit for bedroom.
  • 3-in-1: Our 4,100 BTU DOE (8000 BTU ASHRAE 128) air conditioner also functions as a dehumidifier & fan. This portable air conditioner (45.8 lbs.) has a convenient remote control & top mounted control panel with LED display.
  • Impressive Features: Set the temperature just right with this ac portable air conditioner. Our ac unit portable also has a slide-out washable filter, auto water evaporation, & 24-hour timer.
  • Easy Mobility: Thanks to casters on the bottom and side handles on both sides of the small air conditioner, this air cooler can be moved from room to room without any hassle.
  • Installation Kit: When it comes to fans that blow cold air, this indoor ac unit includes an easy-to-install window kit. A large, vented airflow outlet ushers in cool air. Cools a room approximately 15' x 20'

The Black + Decker BPACT08WT Portable Air Conditioner tops our list of the best energy efficient portable air conditioner. It’s a quiet and powerful air conditioner designed with 5,000 BTU DOE (8,000 BTU ASHRAE). The air conditioner measures approximately 16.5 x 11.5 x 26 inches. 

The design is meant for small rooms of about 150 sq. ft. This means that it’s suitable for dorms, cabins, apartments, bedrooms, living rooms, offices, and campers. Simplicity is also another feature that makes the Black + Decker BPACT08WT Portable Air Conditioner unique. 

It’s also simple to use and install, keeps air both dry and cool, prevents bacteria growth in steamy and hot conditions, and significantly reduces humidity in your room. When it comes to cleaning, the manufacturers designed it to make your work easier.

It has a simple remote control and top-mounted LED display with a 24-hour timer that enables you to control the temperature, clean the filter by sliding it out twice a month, rinse it thoroughly under running water then return it. 


  • Powerful and quiet
  • Ideal for small rooms
  • Easy to install
  • Easy to clean and use
  • It combines 3-in-1 functionality


  • Bulk exhaust hose
  • If the exhaust has a bend, it becomes loud
  • Unreliable cooling abilities

2. Whynter ARC-14SH 14,000 BTU Dual Hose Portable Air Conditioner

Whynter ARC-14SH 14,000 BTU (9,200 BTU SACC) Dual...
  • AWARD-WINNING: Good Housekeeping's 2024 "BEST OVERALL PORTABLE AIR CONDITIONER Provides powerful cooling over large areas" .Air flow efficiency : 253 cubic_feet_per_minute_per_watt
  • POWERFUL & QUIET: 14,000 BTU (ASHRAE) / 9,200 BTU (SACC) cooling capacity | 13,000 BTU (ASHRAE)/ 8,200 BTU (SACC) heating capacity; Noise level (dBA): <56
  • ADVANCED SELF-EVAPORATION: Dual hose operation; Cools up to a 500 square foot space (ambient temperature and humidity may influence optimum performance); Patented auto drain function fully exhausts all condensate automatically in most environments; Dehumidifying capacity: 71 pints per day; Air Flow (at high speed): 430 m3/h / 253 CFM; 3 fan speeds
  • MULTI-FUNCTIONAL & ENERGY SAVING: Four operational modes: Cool, Heat, Dehumidify, and Fan; Cooling thermostatic control (61°F – 89°F)|Heating thermostatic control in ambient conditions above 45° F (61°F – 77°F); Maximum power consumption: 1300 W / 11.6 A; Power supply: 115 V / 60Hz / 1 Phase; Eco-friendly CFC free Green R-32 refrigerant
  • EASY TO SETUP & PORTABLE: Extendable exhaust hose (up to 60″) 5.9" diameter; Window kit dimension: 6.5″ W x 20″ L (minimum), 46″ (maximum); Unit dimensions: 16″ W x 19″ D x 35.5″ H; Activated carbon air filter and washable pre-filter

The Whynter ARC-14SH portable air conditioner is designed to offer mobility and power. Although it has a few drawdowns, such as high energy consumption and an unreliable compressor, if you have a small space that requires proper air conditioning, this is the ideal appliance to consider. It can adequately fit into any bedroom, server room, or office.

The unit also comes with advanced auto technology that typically uses and recycles collected moisture during the cooling process to exhaust hot air. It also features a dual hose operation that offers fast cooling. There are four operational modes included: air conditioner, heater, fan, and humidifier. 

Another notable feature about the Whynter ARC-14SH portable air conditioner is that it improves the air quality through its washable pre-filter and activated carbon filter. The design and performance also make it suitable to have, and it also offers a hassle-free installation capability.


  • Dual hose operation
  • Four operational modes; air conditioner, dehumidifier, fan & heater
  • 14,000 BTU cooling capacity
  • Improves air quality
  • Easy to install
  • Excellent design and performance


  • The compressor is not durable enough
  • High energy consumption
  • It may have cooling issues after long use

3. LG LP0817WSR White Portable Air Conditioner

LG LP0817WSR 115V Portable Air Conditioner with...
  • This Certified Refurbished product is tested and certified to look and work like new. The refurbishing process includes functionality testing, basic cleaning, inspection, and repackaging. The product ships with all relevant accessories, a minimum 90-day warranty, and may arrive in a generic box. Only select sellers who maintain a high performance bar may offer Certified Refurbished products on Amazon.com
  • Portable air conditioner with auto evaporation system
  • 8000 BTU (ASHRAE-128 Standard) / 5500 BTU (DOE 2017 Standard)
  • Uses a standard 115-volt/15 amp electrical outlet (6-ft. long power cord)
  • Cools a room up to 150 sq. ft. with up to 1.8 pints per hour dehumidification

The LG LP0817WSR White Portable Air Conditioner perfectly fits into the description of a low energy portable air conditioner. Not only is this air conditioner portable, but it’s also easy to carry around and cool rooms of approximately 200 sq ft. With this conditioner, you can stay cool and comfortable wherever you go.

It includes an oscillating air discharge that swings up and down to evenly sweep air through the entire room and eliminate hot spots. You can turn off the oscillation using the remote control if you don’t want to use it. The LG LP0817WSR White Portable Air Conditioner features an installation kit that fits horizontal and vertical windows from 18 to 50 inches. 

The kit has detailed instructions to help you install the air conditioner properly. Another beneficial factor about this air conditioner is its sleek touch controls and an LED screen that makes it easier for you to switch between the three modes and two fan speeds simple. There’s an auto-evaporation system that allows for continuous operation without the need to empty the bucket regularly.


  • Cools rooms up to 200 sq ft.
  • Features an installation kit
  • Portable
  • Features an oscillating air discharge
  • Sleek digital touch controls


  • Pretty loud
  • It takes 20 minutes or more to install, depending on how skilled you are.
  • Terrible packaging
  • It may leak after prolonged use

4. Honeywell MN10CESWW Environmental Appliance

Honeywell Home MN10CESWW Environmental Appliance,...
  • Powerful, safe & dependable Cools rooms up to 350-450 sq. ft. Thermal Overload protection for added safety & peace of mind.
  • Quick installation easy-to-install window venting kit included with adjustable window bracket from 19.9". to 47.25"
  • Easy maintenance Washable Filter designed to protect from dust & hair to extend product life & performance. Filter cleans easily under a faucet for easy maintenance.
  • Designed for comfort Enjoy simple digital control with 3 fan speeds, 24 hour energy saving timer & remote control included
  • 3-in-1 appliance Powerful cooling in the summer, Dehumidifier for humid days (removes up to 66 pints/ 24 hours with continuous drain option for long unattended operation), Fan circulates air for everyday comfort. Exhaust Hose Length: 12" to 47".
  • Cooling capacity 10000 BTU (ASHRAE-128 Standard) / 5500 BTU (DOE+ 2017 Standard)
  • Wattage: 1.4 kilowatts

Although durability is an issue with the Honeywell MN10CESWW Environmental Appliance, the manufacturer states that it is built to last. Therefore, this may vary from one user to the other.

This air conditioner includes a washable filtration system, which helps to protect and extend its life. There is also thermal overload protection on the compressor and motor, which offers extra safety precautions for additional endurance and peace of mind for users.

The washable filtration system filters dust, pet dander, and hair from entering the unit, and this helps to reduce air impurities, thereby making it easier to clean the air conditioner. All the accessories are included for quick installation on vertical or horizontal windows. Therefore, this saves you time when it comes to the installation process.

It’s also an energy-saving type of AC, since it reduces the whole house’s energy consumption, as you can set it up in the rooms that you only use. In terms of operation, this AC is essentially quiet due to its dual-motor technology that lowers the noise level. You can set it and forget, plus it’s relatively easy to maintain and store in your home or anywhere.


  • Powerful
  • Safe
  • Easy to install and maintain
  • Easy to clean
  • It offers comfort
  • It saves energy and money


  • Not durable enough
  • It may encounter cooling issues
  • Warranty issues with the manufacturer

5. DELLA 8000 BTU Portable Air Conditioner

No products found.

DELLA is a notable brand that offers a wide range of modern products to customers. Their products provide a long-lasting impact on the tradition of the industry, and they are quite reliable. The DELLA 8000 BTU Portable Air Conditioner features a high-power cooling compressor that cools up to 3,000 sq ft of space. 

It’s an energy-saving portable air conditioner that consumes minimum energy and comes with an expandable window that enables you to install it in any room easily. You can fully count on this AC when it comes to mobility since it features easy-roll caster wheels that help you move it easily from one place to another.

There are 2-way air directions in the AC that helps you spread the air evenly throughout the room, and a control panel has a complete set of selections right at your fingertips. It’s also a user-friendly appliance, as you can quickly access all the functions with one click of a button.


  • 8,000 BTU power cooling system
  • Multi-functional
  • Dehumidifier with 2-speed cooling FAN
  • Quiet
  • Energy-efficient
  • Easy mobility


  • Bright LED lights at night
  • The vent tube lacks a screen
  • Basic remote lacks light for night use

6. Global Air 10,000 BTU Portable Air Conditioner

Global Air 3-in-1 Portable Air Conditioner, 10,000...
  • Stay cool and comfortable wherever you go with our portable air conditioning unit. With 10000 BTU (ASHRAE) / 6,000 BTU (SACC) cooling capacity, it can cover rooms up to 300+ sq ft, saving you time and money. Enjoy the perfect temperature with ease and convenience at your fingertips.
  • 3-in-1 Portable Air Conditioner - AC, Dehumidifier, and Fan: Our portable AC unit not only cools but also serves as a dehumidifier and fan with 3-speed settings. Its convenient remote control makes it easy to switch between modes to achieve the ideal indoor environment.
  • Designed to fit seamlessly into any environment, this small window air conditioner boasts a 3-in-1 functionality with AC, dehumidifier, and fan modes. With low noise levels of only 52-56 dB, you can enjoy a luxurious and quiet experience in any room. Its versatile design makes it a perfect fit for your home, office, bedroom, living room, meeting room, garage, and more. Plus, its easy-to-use remote controller makes switching between modes a breeze.
  • The Global Air portable AC unit for rooms offers a wide range of features to make your life easier. It comes equipped with an automatic swing mode, a built-in 24-hour timer, and both a remote control and push-button control panel, giving you complete control over your indoor air conditioning.
  • Setting up your portable air cooler for a room is a breeze. With the window mount exhaust kit and exhaust hose, installation takes just a few minutes. Plus, the removable air filter can be washed with ease, ensuring that your unit runs smoothly and efficiently.

The Global Air 10,000 BTU Portable Air Conditioner provides a cooling power that’s perfect for a large room of up to 300 sq ft. The AC is cool and comfortable with a 2-speed cooling and fan and 4-way air direction to spread the air in the entire room evenly. 

It features digital controls that provide accurate temperature adjustments and remote control that lets you control it conveniently from across the room. The included self-evaporative system eliminates the need for a water tank. It condenses the water and recycles it to improve the efficiency of the cooling condenser.

The Global Air 10,000 BTU Portable Air Conditioner also offers over-cold protection three minutes restart-delay function and keeps you cool throughout the warm summer season. It’s a portable air conditioner with a window installation kit with detailed instructions on how to set up and install.


  • Includes remote control
  • Self-evaporative system
  • Portable
  • Easy to adjust
  • User-friendly LED display


  • Unreliable hose
  • Inefficient fan when the speed is low

7. Friedrich ZoneAire PH14B Portable Room Air Conditioner

Friedrich ZoneAire PH14B Portable 4-In-One Air...
  • Auto restart: automatically restarts the motor in the event of a power failure or a power outage. Once the power is restored, the air conditioner will resume operation in the last Programmed setting
  • Easily portable: durable castor wheels and side handles make moving room-to-room easy. Cooling Amps: 10.8. Heating Amps: 10.8
  • 3 fan speeds: find your ideal temperature by selecting 1 of 3 fan speeds
  • Air Circulation- 250 cubic feet per minute. Moisture Removal- 5 pints per hour
  • 13500 Btu cooling and 10700 Btu heating ZoneAire portableheat pump has an EER of 9.5 for rooms up to approximately 700 sq ft.
  • Dual-hoses for closed loop cooling and exhaust functions for up to 40% faster cooling thean single hose units
  • 4-in-1 system is an air conditioner, heater, dehumidifer and a fan
  • Condensate overflow protection will automatically shut off the unit if the tank should become full
  • 24-hour timer

If you’re looking for an easy-to-install and portable air conditioner power consumption type of AC, the Friedrich ZoneAire PH14B Portable Room Air Conditioner perfectly fits into this description.

It comes with a 4-in-1 system which includes air condition, heater, dehumidifier, and a fan that offers all-year-round air conditioning comfort. The installation of this AC is easy due to its portability, casters, and side grip handles. 

There are about 3 fan speeds that you’ll find in this AC, a 24-hour timer, a 6-feet long power cord, and it easily plugs into a 115V outlet. It has a dual hose design that allows you conditioned air to return to the room instead of going out. Therefore, this helps to cool the room up to 40 percent faster than using a single hose design.

As you may know, sometimes it may be challenging to find the perfect storage space for an AC. However, the ZoneAire PH14B has an excellent design that makes it easier to store even in a minimum space. There are also switch to fan mode, remote control, and dehumidification features included in this AC, making it worth buying.


  • Self-evaporation condensate system
  • Built-in drain pump
  • Auto-restart after a power outage
  • 4-in-1 system
  • Portable


  • You need to remove the hose to dehumidify
  • Noisy
  • It can break down faster after prolonged use

8. Black + Decker BPACT08WT Portable Air Conditioner, 8,000 BTU

BLACK+DECKER 8,000 BTU Portable Air Conditioner up...
  • Portable AC: Use this personal air conditioner (15.3” x 14” x 24.8”) in rooms up to 350 sq. ft. Stay cool in the hot summer months and sleep well with this BLACK+DECKER ac unit for bedroom.
  • 3-in-1: Our 4,100 BTU DOE (8000 BTU ASHRAE 128) air conditioner also functions as a dehumidifier & fan. This portable air conditioner (45.8 lbs.) has a convenient remote control & top mounted control panel with LED display.
  • Impressive Features: Set the temperature just right with this ac portable air conditioner. Our ac unit portable also has a slide-out washable filter, auto water evaporation, & 24-hour timer.
  • Easy Mobility: Thanks to casters on the bottom and side handles on both sides of the small air conditioner, this air cooler can be moved from room to room without any hassle.
  • Installation Kit: When it comes to fans that blow cold air, this indoor ac unit includes an easy-to-install window kit. A large, vented airflow outlet ushers in cool air. Cools a room approximately 15' x 20'

Finally, this is a self evaporating portable air conditioner on the list – this time from Black and Decker. Black and Decker make some fantastic home heating and air conditioning systems. Their products also come with long warranties, and you get access to invaluable customer support.

This particular AC, model BPACT08WT, is an 8,000 BTU unit, perfect for small rooms around 200 square feet. It provides fast, steady cool air and doesn’t need installation, though it comes with a 5-foot window adapter should you feel like hanging it on the window. It plugs into a standard 115V outlet, so you don’t need to worry about new wiring.

Other key features of Black and Decker include simple remote control and a top-mounted LCD display with a 24-hour timer. Together, these features allow you to closely control the temperatures in your home without unnecessary energy wastage.

A reusable filter, three fan levels, and self-evaporating operation are other important functions. It’s rated 8.94 EER.


  • Compact size for small spaces
  • Full window kit included
  • Full-function remote control
  • Castor wheels included
  • 1-year parts. 5-year compressor warranty


  • Slightly noisy at up to 75 decibels
  • Small size best suits smaller applications
  • No heating function

Why Choose An Energy Efficient Portable Air Conditioner

Perhaps we should begin by understanding what energy efficiency means. What does it mean when an air conditioning (AC) system is energy efficient?

Efficiency means doing more with less. Therefore, energy efficiency is the quality of a machine to use less energy to run at optimal levels. Another way to look at it is “squeezing as much useful power as possible out of every watt/BTU.”

The Environmental and Energy Study Institute (EESI) defines it as “using less energy to perform the same tasks – that is, eliminating energy wastage.”

The Natural Environmental Research Council, meanwhile, defines it as “using less energy to provide the same level of energy.”

Finally, the US Energy Information (EIA) defines it as “using technology that requires less energy to perform the same function.”

Benefits of Choosing the Most Energy Efficient Portable Air Conditioner

There are endless reasons why homeowners should strive to attain energy efficiency in their homes. These include;

  • Significantly reduces your energy bills: As a homeowner, energy costs can make up a massive portion of your monthly expenses. According to studies, states such as Hawaii and Rhode Island spend 4.5% and 3.4% of their annual incomes, respectively, on electricity alone. According to the US Department of Energy, you can save anywhere between 5-30% of those costs by switching to energy-efficient appliances.
  • Earn a great return on your investment: Granted, energy-efficient appliances typically cost more upfront than less-efficient alternatives. However, over the life of the appliances, energy-efficient options guarantee a greater return on investment. The savings over the years will offset the initial cost and ultimately result in savings.
  • Enhance the quality of your life: When you optimize your energy use, you effectively increase the comfort levels in your home. In many cases, you’ll have the right indoor temperature, proper humidity, and the right ventilation, resulting in a reduced risk of mold and allergens, and better health. In fact, some experts say up to 75% of energy efficiency benefits are health-related.
  • Protect the environment: Finally, if you really care about the environment, energy efficiency becomes a no-brainer. Homes were responsible for 19% of national greenhouse emissions in 2016. Investing in more energy-efficient appliances and practices can reduce your carbon footprint by 25-30%.

How to Read an Air Conditioner’s EnergyGuide Label

Before you buy any product, it’s always recommended to consider various factors, which may help you prove whether it’s suitable for you or not. In our buying guide section, we’ll offer you essential insights and answer crucial questions to help you buy an AC that completely meets your needs. 

most energy efficient portable air conditioner guideWhen buying an AC, it’s important to remember that it comes with an energy guide label that can significantly help you save on energy costs if you keenly understand everything that has been outlined in it. 

  • EER – This means Energy Efficient Ratio. It refers to the number of electrical watts an appliance uses to achieve the cooling output. 
  • SEER – This means Seasonal Energy Efficiency Ratio, and it’s usually included in central air conditioners. Like the EER, having a higher SEER value means that it offers excellent energy efficiency and savings. Most of the older air conditioners tend to have SEER system values of 6 or less. 
  • The label’s top has the list of the manufacturer, model number, appliance type, and capacity. 
  • The middle of the label shows the line scale, which helps you differentiate how a specific model compares energy efficiency.
  • The annual operating cost is shown close to the bottom of the label.

When you’re reading an AC’s energy guide label, note that you’re not looking for a specific number. Instead, you’re looking for a unit score compared to the other units in its class or state. That means you need to spend time researching the energy-efficiency of an air conditioner and how much it translates to saving money on the home cooling costs. 

Some companies may extend rebates to buyers that purchase appliances with high efficiency. Therefore, it’s advisable to call the local utility provider and determine if your unit qualifies for a rebate to see if you can save money.

What Makes an Energy Efficient Air Conditioner?

There are many factors to consider when assessing the best energy efficient air conditioner. Let’s begin with the well-established efficiency rating – EER and SEER.


EER is short for Energy Efficiency Ratio. It is a measure of how efficiently an air conditioner uses electricity to remove heat from your home.

The EER rating is used for all air conditioners, from window to wall and central air units. The ratio is now also found in the literature of split air systems. One of the very first AC manufacturers to list the EER rating on their appliances was Rheem.

The EER rating of your air conditioner should be listed in the specifications section of the user guide. Many manufacturers also display it in the Energy Guide label. The Energy Guide label is a yellow and black tag attached to most home appliances. It tells shoppers how the appliance uses energy (more on this later).

It’s worth noting that the EER measurement is only for air conditioning. A few ACs double up as heat pumps for supplemental heating in the colder months. EER ratings don’t measure the heating efficiency of heat pumps. Instead, heating efficiency is measured by a separate metric – the Heating Seasonal Performance Factor (HSPF).

How EER is Determined

The Energy Efficiency Ratio is a very specific measurement. It measures how efficient an air conditioner cools under the following conditions;

  • The outdoor temperature is 95F
  • Indoor temperature is 80F
  • The relative humidity is 50%

Every EER of every AC is measured relative to these specific conditions in a laboratory. It’s the only way to compare “apples to apples.”

Once the necessary measurements are taken, the EER value of the AC under test is calculated by dividing the number of cooling BTUs generated by the watts of electricity consumed over the same period. In other words;

EER = BTU/hour divide by watts per hour

If you have these measurements (BTUs/hour and watts/hour) for your AC (which you should), you can easily calculate the EER of the appliance. Just divide the two figures. For instance, if the AC is rated 18,000 BTU and 1,590 watts, then the EER is calculated as 18,000/1,590 = 11.3 EER.

The figure is actually a ratio (as suggested in the name (EER)). So, an 11.3 EER should be listed as 11.3:1. However, since the readings are BTUs per single watt of electricity, it’s a lot more straightforward and understandable to list it without the to-one ratio.

Factors that Affect EER Rations

Two key factors affect the EER performance of air conditioners – prevailing temperatures and humidity.

  • Temperature: As already mentioned, EER is calculated when the outdoor temperature is 95F. If the temperature is higher than 95F, the efficiency might be lower. Lower temperatures typically result in higher efficiency figures.
  • Humidity: The EER value is likely to be even further from the true value if the humidity is higher than 50%. Air conditioners are most efficient when humidity is low. The more moisture in the air, the harder it is for the AC to run, thus lower efficiency figures. Lower than 50% humidity will consequently return a higher EER efficiency value.

What’s a Great EER Rating?

Unfortunately, the highest EER rating isn’t always the best. How much the rating fits your needs will depend on several factors, especially your geographic location.

In hotter, more humid climates, a higher EER rating would make more sense. It will cost you more, but you’re guaranteed significant savings through the years. The average payback period is about five years, depending on your climate. Ann 11+ EER rating would be excellent.

Cooler, less humid climates can do with lower EER ratings since the AC doesn’t need to work as hard as in hotter climates. An EER rating in the 10-11 range would be ideal.


SEER is short for Seasonal Energy Efficiency Rating. It’s the cooling output of an air conditioning system divided by electricity consumption over the same period. The higher the SEER value, the more efficient the AC.

What’s the Difference between EER and SEER?

The main difference is that SEER measures the efficiency of an AC over a cooling season while EER measures the same appliance’s efficiency throughout the year.

While EER is measured under specific and very strict climatic conditions, SEER values aren’t very strict about prevailing temperature and pressure because these two tend to vary significantly over a cooling season. In many instances, SEER values are measured at any temperature between 60°F and 100°F

For this reason, the accuracy of the SEER rating is sometimes questioned. For instance, a 16 SEER AC in a cool climate might only achieve 14 SEER performance in a hot climate. It’s been found that the efficiency drops by 1 SEER for every 5°F temperature drop.

This is partly why some air conditioning systems still don’t use the SEER rating. Only mini-split systems (air pumps) and central air conditioners widely use the rating.

Most Common SEER Ratings

The lowest possible SEER rating is 13 SEER. These ACs are the least efficient models rated under the SEER model. They are also only allowed in colder climates such as Canada and the northern states of the US. For the warmer states, a minimum rating of 14 SEER is required.

Above the minimum, ACs can be as efficient as 26 SEER, while those that double up as heat pumps typically max out at 25 SEER.

Which is the Best SEER Rating?

As with EER ratings, it depends on your cooling needs and climate/location. You’ll benefit more from a higher SEER AC if living in a warmer climate.

That said, there are a few things you should know about even the most energy efficient air conditioner in the different SEER ranges. They are slightly different from one another;

  • 13 to 16 SEER ACs: Are mostly single-stage air conditioners. They run at maximum capacity when on and tend to turn on and off a lot, resulting in significant cold/warm imbalances. These units also remove less humidity. Many ACs in this category have multi-speed blowers. They’re the cheapest ACs.
  • 16 to 20 SEER ACs: Are typically two-stage air conditioners. They have two working capacities – Low (about 40% of total BTU) and High (100% of BTU power). In the Low setting, the units consume less power and generate gentler, longer cooling. There’s also a better temperature balance. Many of them have variable-speed blowers.
  • 19 to 26 SEER: Are variable-speed compressor air conditioners. The compressors automatically self-regulate to deliver optimum comfort while consuming the least energy. Sometimes they run on just 25% of the BTU rating depending on indoor air conditions. When more cooling is needed, the unit will automatically adjust output to meet the increased demand. They are the best ACs you can buy.

Other AC Energy Efficiency Metrics/Ratings

Although EER and SEER ratings are the most important metrics when shopping for an energy efficient air conditioner, there are a few other considerations to keep in mind;

Energy Star Rating

The Energy Star label was established in 1992 to help consumers easily identify and pick the best products that promote and support energy efficiency in the home. Energy Star products are better at utilizing energy and emit fewer if any, greenhouse gases.

For an appliance to become Energy Star certified, it must adhere to strict guidelines and meet specifications established by the Environmental Protection Authority. These specifications include;

  • The product must show an increase in energy savings for consumers throughout the country.
  • The product cannot be less than what consumers expect in terms of features and performance.
  • Consumers must see a reduction in monthly utility bills even if the Energy Star-rated product costs more than non-certified alternatives.
  • Improved performance and reduced energy consumption should be provable through testing at any given time.

Benefits of Energy Star ACs

There are several benefits of buying an Energy Star-certified air conditioner. Reading from the program’s eligibility criteria, you’re guaranteed;

  • A minimum EER rating of 10.4 for ACs with non-louvered sides and 11.2 for models with louvered sides
  • A CEER rating of 10.2 for AC models with non-louvered sides and 11.0 for models with louvered sides
  • An energy saver setting (mode) at which the appliance consumes very little energy for cost savings.
  • Filter reminders that provide visual notifications, recommending the filter to be checked, cleaned, or replaced.

In general, Energy Star-rated products are between 5% and 30% more efficient than non-certified alternatives.

CEER Rating

Finally, you also need to consider the Combined Energy Efficiency Rating (CEER). CEER is mostly associated with room air conditioners and window ACs. It measures the unit’s combined efficiency when it’s on standby and when it’s actually cooling the house.

It’s defined as the ratio of measured cooling output (in BTU/hour) to the average amount of electricity consumed per hour (In watts) and standby electric power consumption (also in watts).

As of June 1, 2014, the CEER metric is the measurement used in determining whether an appliance qualifies for Energy Star certification. Before that, EER measurements were used.

How AC Sizing Impacts Energy Efficiency

The AC’s size has a significant say in how efficiently it cools (or warms) the intended space. That’s because the AC capacity required to meet the air conditioning needs in any space depends on that space’s dimensions. For a smaller room, a smaller AC will suffice. A bigger room, meanwhile, requires a higher-capacity AC.

However, this doesn’t necessarily mean that a bigger AC would automatically make you feel more comfortable in the hot months. It doesn’t work that way. You may feel cooler, yes.

But, is comfort just about feeling cooler in the warmer weather? No. Indoor comfort incorporates many other factors, including humidity and safety. A more powerful AC will lower the temperatures to the desired levels, may compromise these other two aspects of indoor air quality.

It’s been shown, for instance, that an AC that’s too big for a room will reach the thermostat setting way before the desired dehumidification level is achieved. This usually results in a “clammy” and uncomfortable climate.

How to Properly Size an Air Conditioner for your Room

Where possible, you should ask an HVAC professional to help you determine the right-size AC for your home. But, if you decide to do it on your own, proceed as follows;

  1. Calculate the square footage of your home or the room(s) you’d like to air condition. The assumption here is that your room has the standard 8-foot ceiling.
  2. Divide the figure in step #1 by 500.
  3. Multiply the figure from #2 by 12,000. The result is the number of BTUs required to cool your space effectively.
  4. Add 380 BTUs for every person who works in the space. If this number varies, take an average figure and multiply it by 380, then add to the figure in #3.
  5. Add 1,000 BTU for every window, including the window where the AC is installed if you’re buying a window AC. For kitchen windows, add 1,200 BTU for each.

The final figure after step #5 is the AC capacity in BTUs required for your space/home. Since ACs are rated in tons, you’ll need to convert the figure to tons. 1 ton = 12,000 BTU.

Window AC vs. Portable AC vs. Mini Split Systems

Window ACs, portable ACs, and mini-split systems tend to vary in terms of features and usability. 

energy star portable AC vs window AC

Window AC

Window AC is a single unit type of air conditioner that can be installed seasonally or permanently. It is located in a pre-existing window and is mostly poorly insulated. 

Window AC units are easy to find, affordable, quiet, and drain to the outside. Their drawdowns include being challenging to insulate, they aren’t pretty, not all windows support them, and they are a hassle to move.

Portable AC

A portable AC is also a single unit, it’s quick and easy to set up and move from one room to another. The good thing about a portable AC is that it doesn’t require insulation, unlike the window AC.

The disadvantages of portable AC units include being less efficient, noisy, and expensive.

Mini Split Systems

On the other hand, the split AC has two units – one indoors and the other one outdoors. It can be permanently installed, and the installation only requires minor construction. The mini-split AC is also very well insulated. 

Split AC units also have disadvantages, such as being difficult to install, costly, noisy, large, and intrusive. 

Each of these AC units has its advantages and disadvantages, but they serve various purposes. Therefore, it’s up to you to decide the ideal type of AC you want to buy before making that move.

What to Look for When Buying the Most Energy Efficient Portable Air Conditioner

Before buying an energy-efficient portable air conditioner, there are various things that you need to look for to ensure you get the best deal and an appliance that satisfies your needs.

Check out these factors to consider below.


When choosing an air conditioner, size is a significant factor to consider. If you want the best energy-efficient portable air conditioner, avoid choosing a large AC.

An oversized unit will cool the air in your room and leave it clammy or damp. A smaller unit, on the other hand, will need to overwork to maintain the appropriate temperature. Therefore, you need to choose the right size that will match where you’re placing the AC.


The benefit of most ACs nowadays is that they come with digital displays to help you set the right temperature and even schedule the time you want the AC to turn off. Therefore, you need to check on the programmable temperature settings before purchasing an AC.

Energy Efficiency

Will the air conditioner you want to buy save you energy and minimize electricity cost? This is a crucial question you need to ask yourself before any AC. Look out for an AC that saves on energy.

EER and SEER Ratings

These two ratings help measure the energy efficiency of an AC in BTUs, and they are also important factors to check before buying a unit. A good air conditioner has a higher rating than any of these two measurements since it will offer you high efficiency.

Energy Star Certification

When buying an AC, try as much as possible to look for the blue “ENERGY STAR” certification because it is a sign that the unit meets or exceeds the high-efficiency standards.

WIFI Feature

Some air conditioners are WIFI-enabled, and you can adjust them with your smartphone. These are known as smart portable air conditioners, and they offer so much convenience to users. 

Other portable air conditioners reviews

Best portable air conditioner for humid climate

Best portable air conditioner for tents

Budget-friendly portable air conditioner under $200

Best portable AC under $300

Best portable AC under $400

Ways to Maximize Your Energy Efficient Air Conditioner

There are several ways that you can implement to maximize the energy-efficiency of your air conditioner. They include:

  • Set your AC to 78 degrees during the summer to manage the cooling costs properly.
  • Turn off all the unnecessary appliances and lights since they generate heat removed by the air conditioner.
  • Program the thermostat to increase the temperature by a few degrees when there’s no one at home. This will help to decrease your AC’s workload.
  • Use ceiling fans to circulate the air efficiently than the AC can. They tend to use less energy.
  • Insulate and seal points where the AC unit enters your home. 
  • Clean all window units monthly by wiping down the vents and rinsing them afterward.
  • Properly clean all your ducts if you happen to have a central air conditioning system in your home.

How to Save Electricity with Air Conditioners

Even after you start using the AC, you can take steps to increase the unit’s energy efficiency. Consider the following;

Keep the vents free from debris

Debris in the vents can not only cause noise but also block airflow, resulting in reduced efficiency. Make it a habit to walk around the AC to check whether there’s debris blocking airflow. If you notice any debris, remove them right away. You’re also advised to vacuum the AC once in a while and schedule professional maintenance at least twice a year.

Close all doors and windows

The conditioned air in your home can easily escape through the doors and windows. Closing all entryways and windows helps keep the conditioned air indoors. Whenever you feel like airing out the home, shut off the AC first, then open the doors and windows for a while. Then, close them again before you turn off the AC.

Ensure proper insulation

Air leaks are another significant cause of efficiency losses in the home. Where leaks are present, the cool air will use them to escape to the outdoors, leaving your home hot even when the AC is on. The result is that the AC needs to work harder and longer to achieve and maintain the desired indoor climate. Both of these negatively affect efficiency. Proper insulation eliminates this problem.

Thermostat placement is important too

If the thermostat is placed close to warm areas, such as close to a sunny window or a lamp, it may not gauge your temperatures correctly, likely resulting in incorrect indoor air conditioning. Usually, you may also end up paying more for the energy you don’t even need. Professional technicians know this, which is why they’ll never install the thermostat close to a window.

There are many other steps you can take to improve air conditioning efficiency in your home for greater comfort and lower energy bills. These include;

  • Schedule regular preventive maintenance
  • Consider installing a zoning system
  • Don’t use the registers to control the temperature
  • Avoid using the oven or dryer
  • Change the AC filter as advised by the manufacturer
  • Insulate any exposed ductwork
  • Clear the drain line

Most Energy Efficient Portable Air Conditioner FAQs

If you’re still struggling with a few questions at the back of your head, the following are answers to common energy-efficient AC questions;

Does Energy Saver Mode in Air Conditioning Save Money

Yes. An energy saver mode can help save energy and money. It’s partly why Energy Star demands an energy-saving mode as part of the requirements for appliance certification.

How Much does an Air Conditioner Cost to Run Per Hour?

On average, it costs $0.06 to $0.88 to run an AC per hour. However, this is just an estimate. The actual cost will depend on other factors, such as the capacity (BTU) of the AC and the cost of electricity in your location.

Is it Cheaper to Run a Window or Central Air Conditioner?

As we’ve already seen, central/ducted air conditioners are more efficient to run. This would translate to lower operational costs compared to similarly-rated ACs. However, you need to remember that central ACs are typically much larger (capacity-wise) than window ACs. In the end, therefore, it costs more to run a central AC.

Portable Air Conditioner vs. Window Air Conditioner

Portable air conditioners are generally more efficient than window air conditioners. Also, since portable ACs can be placed right where the air conditioning is needed, the benefits are greater. Window ACs, however, typically cost less than similarly-rated portable units.  

Mini Split vs. Central Air Conditioner

Everything considered mini splits are the most energy-efficient way to air condition your home. Granted, central ACs rank better with regard to efficiency ratings. However, mini splits offer a kind of convenience that greatly boosts overall air conditioning efficiency.

Wrap Up

The search for the best portable air conditioner can be a long and tedious process. However, with the right insights, you can purchase a high-quality AC that will serve you for a long time. There are many ACs out there from different manufacturers that compete to outdo each other.

Due to this, you may find yourself overwhelmed with all the information provided by experts and consumers alike. The most important thing you need to keep in mind is choosing a high-efficiency portable air conditioner requires the utmost scrutiny and research. 

Hopefully, you’ve learned something from this portable air conditioner buying guide to help you buy the right AC for your home. Please feel free to ask any questions or offer valuable insights in the comment section below. You can also shoot me an email, and I’ll be happy to respond as soon as possible.