Buyer's Guide

Most Energy Efficient Window Air Conditioners Reviewed

Investing in an energy efficient window AC can pay off – and it doesn’t take long to see the savings.

Easy To Install

Friedrich Chill CP06G10B
Friedrich CP06G10B

This 6000 BTU air conditioner has an EER of 11.2 and an estimated year cost of $50 (high setting).

Most Energy Efficient Window AC Unit

Amana AMAP050BW 5000BTU
Amana AMAP050BW

This 5000 BTU air conditioner has an EER of 11 and an estimated year cost of $45 (high setting).

Quietest AC Unit

Haier ESAQ406T
Haier ESAQ406T

This 6000 BTU air conditioner has an EER of 12.2 and an estimated year cost of $44 (low setting).

Energy efficient window air conditioning units aren’t just financially smart – they also reduce your carbon footprint and do a better job of cooling your home.

The U.S. Department of Energy estimates that the average household spends 6 percent of its energy use on cooling spaces in the home. Nationwide, that’s about $11 billion each year – and a massive area of improvement that many Americans are eager to decrease.

With the right appliances and energy use, it’s completely possible. One of those appliances is window air conditioners, which have typically had issues with energy efficiency in the past. However, manufacturers in the last few years have made strides in creating efficient, smarter ACs that do a better job of managing energy use and cooling the home.

Today, we’ll look at some of the most energy efficient window air conditioner units available, and why it’s a good idea to get one that’s on the higher side of efficiency. The Department of Energy estimates that switching to a high-efficiency window AC can save you between 20 and 50 percent on energy costs, and doing small, simple things like cleaning and replacing your filters as needed can save even more usage.

“If all room air conditioners sold in the United States were ENERGY STAR® certified, the cost savings would grow to more than $350 million each year, preventing more than 6 billion pounds of greenhouse gas emissions annually,” says ENERGY STAR®, “equivalent to the emissions from over 570,000 vehicles.”

ENERGY STAR® compliant ACs must meet higher standards for energy use and efficiency, but they also save an average of 9 percent less energy. These units may be slightly more expensive than lower efficiency models, but over time, the money saved by less energy use more than makes up for the higher sticker price.

After researching and analyzing 40 units from manufacturers like Danby, Friedrich, Frigidaire, GE, Haier, Kenmore, LG and more, we found several units that stood out based on their efficiency – as well as overall performance and customer satisfaction.

Although we focused primarily on the EER ratings of each unit, we also took into consideration the industry and customer feedback on each product. For example, if a unit had an excellent EER ratio but poor reviews and feedback, we didn’t include that model in our final analysis.

Finally, we recommended window AC units based on their cooling performance and the size of the rooms being cooled. This means we chose a high-performing efficient AC for small bedrooms (6,000 BTUs), medium-sized rooms (8,000) and large spaces (10,000+ BTUs).

Here are the most efficient window air conditioners based on their energy efficiency ratio, overall performance, industry reviews, and user feedback.

The Amana AMAP050BW is our Editor’s Choice for overall performance, efficiency & value for money.

The Friedrich Chill CP06G10B is ideal for small rooms, the LG LW8016ER is great for medium-sized rooms, and the Frigidaire FGRC1244T1 is our top choice for large rooms.

Finally, the Haier model is our pick for the quietest option, and the Danby DAC080BGUWDB is our budget pick for those looking to buy a solid, efficient window AC at a lower cost.

Energy Star Air Conditioners Compared

(sq ft)
Amana AMAP050BW15011$45Check Build

Check Amazon

Friedrich Chill CP06G10B25011.2$50Check Sylvane

Check Amazon

LG LW8016ER34012.1$60Check Sylvane

Check Amazon

ARCTIC AW6005E260.512.1$50Check Price
Frigidaire FGRC1244T155012$90Check Price
Haier ESAQ406T25012.2$44 (Low Setting)Check Price
Danby DAC080BGUWDB35011.3$60Check Price

*Estimated/approximate costs per year based on brands testing, information and specifications

Why It’s Smart to Go Efficient

Because cooling a home is such a large expense for households, using energy efficient appliances can make a significant difference in energy use, cost and performance over time.

Some of the main benefits to using the most efficient AC units include:

  • lower energy bills: these units have better parts and materials that make better use of energy, which lowers your usage rate and thus, your energy costs
  • improved environmental footprint: using less energy can help reduce the overall energy use of your home, and decrease your carbon footprint in the big picture
  • increased cooling performance: using an efficient unit will cool the same room down quicker than a less efficient model, which means you get more comfortable, faster
  • better quality: models with higher efficiency are typically made with better parts, which means the unit may be quieter than others and will have to run less to cool the air (also see: the quietest portable air conditioners)
  • smarter features: ENERGY STAR® compliant window units must have “smarter” features like an energy-saving mode and automatic reminders to replace the filters, both of which can make a significant dent in the energy you use each year

Understanding Cooling Power

Before explaining how energy efficiency works, it’s important to know how cooling power is measured with window ACs. These units’ power is measured in BTUs or British thermal units. This is calculated in terms of how much a unit can cool the air around it in an hour.

On the lower end of the spectrum, there are 5,000 and 6,000 BTU units that are meant for small rooms and spaces. On the larger end, you’ll find 10,000 and 12,000 BTU units meant for larger areas like living rooms, offices, and master bedrooms. There are also commercial and heavy duty units that go up to 25,000, though they are rarely as energy efficient as smaller air conditioners, so we’ll be focusing primarily on smaller residential options.

So why’s it so important to get the right sized air conditioning unit for your space? Because a bigger unit isn’t necessarily better.

“In fact, a room air conditioner that’s too big for the area it is supposed to cool will perform less efficiently and less effectively than a smaller, properly sized unit,” says the Department of Energy.

If you buy an efficient 12,000 BTU unit but place it in a small room that’s smaller, it doesn’t matter how efficient that model is – you’re essentially reducing your efficiency because the unit doesn’t match the size of the room.

Instead of focusing on pure cooling power, then, it’s ideal to match your room size to the BTU rating needed to cool that space. The Department of Energy says a general recommendation is about 20 BTUs per square foot, and ENERGY STAR® offers this helpful breakdown of room sizes.

Energy Star Savings Table Air Conditioners


What is Energy Efficiency Ratio (EER)?

Now that we’ve discussed BTUs, we can look at a metric that looks more at the actual efficiency of a window unit.

To find the most energy efficient units, you can look at the unit’s EER number, or energy efficiency ratio. “The EER is the ratio of the cooling capacity (in British thermal units [Btu] per hour) to the power input (in watts),” says the Department of Energy.

The higher the EER, the more efficient the air conditioner.

As an example, let’s say you have an air conditioner that’s rated to 6,000 BTUs, and it takes 600 watts to run. The calculation would be 6,000 divided by 600, which equals 10. This unit’s EER would be 10.

In general, the most efficient window ACs have an EER of 12 or above, though this depends on the size and cooling power of the unit. In general, it’s a lot easier for a smaller 5,000 BTU or 6,000 BTU unit to have that type of efficiency than it is for a 12,000 BTU unit that’s larger, bulkier and requires more heavy-duty parts to cool larger rooms and spaces.

“An air conditioner’s EER rating is best used to objectively compare air conditioners or to do any type of load or engineering calculation,” says Tim at All Systems Mechanical. “Because it is not diluted by additional inputs, the EER value, in my opinion, is the most accurate way to compare two different HVAC units.”

As we’ve discussed in our research on small portable air conditioners, many air conditioners actual cooling power in terms of BTU is often lower in real-life settings, which means the EER should be used as a benchmark more than anything else. A unit with an EER rating of 12 or above will be more efficient than one below the mark, even taking into consideration changes and differences in real world cooling power.

The most energy efficient models are also ENERGY STAR® compliant. To receive this label, an air conditioner must meet higher-than-normal standards for energy use and efficiency. These standards are set by the government and include criteria like:

  • at least 10 percent higher efficiency than government standards
  • better materials and parts for more efficient energy use
  • better performance for consumers nationwide
  • reduced energy costs in order for users to recoup upfront expense of purchase
  • features like energy-saving mode and filter reminders

Manufacturers can meet these and other requirements by assembling window ACs that have higher quality compressors, fans and surfaces that more efficiently use the energy it takes to run the unit.

Click here to learn more about how appliances can earn the ENERGY STAR® label, or view the Key Product Criteria for room air conditioners.

7 Most Energy Efficient Window ACs Reviewed

These are our top choices in window ACs that will save you money. There are hundreds of products on the market. This list of 7 has been carefully chosen and we have covered a variety of sizes for any room.

1. Amana AMAP050BW Window-Mounted AC

Editor’s #1 Choice

Estimated Yearly Cost$45
Weight52 lbs
Dimensions16 x 15.3 x 12.5
WarrantyYes – 1 Year

The top pick for most energy-efficient window-mounted AC unit is the AMANA 5,000 BTU model.  It’s Energy Star certified and has an 11 EER, according to the manufacturer. This mid-range energy efficiency rating is just one of the reasons that this is a go-to window unit for efficiently cooling down the home.

The 5,000 BTU rating means that the AMANA can cool down a room up to 150 square feet, making it a great choice for a large bedroom or living space. While it cools, it also works to dehumidify and can remove up to 1.06 pints of water every hour.

The AMANA comes with 2 different cooling modes to use less energy and has proven to show results in reducing utility bills of homeowners. The ‘low’ fan mode gradually reduces the air temperature and is a cost-effective solution for owners concerned about their power bill.

You never have to worry about the room overheating after a power failure; the AMANA unit automatically restarts as soon as the power is restored. Installation and maintenance can both be done on your own, even if you don’t consider yourself overly handy. The easy-install window mounting kit is included, so just follow the manufacturer’s provided instructions.

For maintenance, AMANA says that it’s “made easy with the removable and washable air filter. Simply rinse every few weeks to keep your air conditioner at peak performance.”

There’s even a “clean filter” light that alerts you when it’s time for a filter wash or change. As long as you follow the room square footage recommendations, there won’t be one inch of space that goes uncooled thanks to the 8-way directional air louvers.

This unit has everything you could ever ask for, especially when it comes to staying efficient with your cooling needs.

2. Friedrich Chill CP06G10B Window Air Conditioner

Best for Small Rooms

Estimated Yearly Cost$50
Weight60 lbs
Dimensions20.9 x 18.4 x 14
WarrantyYes – 5 Year limited

The Friedrich Chill CP06G10B is one of the best-selling window air conditioners on Amazon and was recently named the best window unit for small spaces by The Spruce.

With a 6,000 BTU rating, the CP06G10B is ideal for rooms from 150 to 250 square feet, and offers an EER rating of 12.2, making it ENERGY STAR® qualified.

This model comes with everything you’d expect from an up-to-date window unit: digital remote, digital thermostat, 24-hour timer and an auto-restart function that saves previously used settings. Three cooling speeds and an “Auto Air” system maximizes air movement and circulation, which helps keep the unit performing smoothly and prevents hot pockets of air.

The installation kit allows you to use the CP06G10B in a window or through the wall, and an EntryGuard anti-intrusion feature helps make the unit avoid becoming a security hazard.

Filter reminders and cleanable, antimicrobial filters make this an easy-to-maintain air conditioner, and with a 1-year limited warranty, you’ll be covered for your first full season of use.

As one of the highest-rated window ACs on Amazon, it has plenty of perks, and one of the only downsides is that at 60 pounds, it’s one of the larger 6,000 BTU window units, though its dimensions aren’t as bulky as you may think.

3. LG LW8016ER 8,000 BTU AC

Best for Medium-Sized Rooms

Estimated Yearly Cost$60
Weight58 lbs
Dimensions19.6 x 19.4 x 12.4
WarrantyYes – 1 Year

LG makes some of the most commonly used air conditioners on the market, and their LW8016ER maintains the brand’s reputation and performance well.

It’s received high marks from Consumer Reports – one of the best rated 7,000 to 8,500 BTU options – and it was also named the air conditioner of choice by Wirecutter, who say that this unit is “the window AC you should probably get, especially if it’s for an office, den, or other room where you won’t be sleeping.”

That last remark is due to the LG’s slightly higher-than-average noise rating, which is listed as 54 dbA indoors and 60 dbA outdoors. Though this is slightly louder than what may be comfortable for some users, it’s also not necessarily high enough to turn off most users.

The 8,000 BTU unit is ideal for rooms between 250 and 340 square feet, and the 12.2 EER rating makes it ENERGY STAR® qualified – with all the features of these appliances, such as energy-saving modes, filter reminders and solid performance features.

Two-way air direction and three cooling speeds give you plenty of flexibility in finding your comfort zone, and a digital remote helps you set it and forget from across the room. At 58 pounds, it’s a relatively small size for a 8,000 BTU unit, and the outside has an “anti-corrosion coating” that’s patented by LG. This helps the unit sustain the elements through summer and the rest of the year if necessary.

A one-year parts and labor warranty covers you for early-use issues, but the user feedback on the LG LW8016ER is solid, especially considering the industry average reviews for window ACs – even good ones – can be less than stellar (mostly due to inflated expectations related to cooling performance).

4. Frigidaire FGRC1244T1 Window Air Conditioner

Best for Large Rooms

Estimated Yearly Cost$90
Weight70 lbs
Dimensions19.8 x 19 x 14.5
WarrantyYes – 5 Year Limited

The Frigidaire FGRC1244T1 is one of Consumer Reports‘ best rated recommendations for window air conditioners, and there’s a reason why: its cooling performance is matched by Wi-Fi connectivity and other “smart” options that make this one of the most efficient and convenient units available today.

At 12,000 BTUs, the FGRC1244T1 is rated to cool rooms up to 550 square feet. It has an EER rating of 12.0, and according to Frigidaire’s corporate website, the unit is ENERGY STAR® qualified. However, the AC is not currently listed on ENERGY STAR®’s website, though the stated EER, if accurate, would place it into ENERGY STAR® compliance.

Where the FGRC1244T1 excels is flexibility and convenience. Download the Frigidaire app and you can control the temperature and settings of your AC from anywhere. Cool your home down before you get to work, or turn the unit off while you’re out at night. You can also control the FGRC1244T1 with Amazon Alexa and Google Assistant, making it one of the most versatile “smart” appliances on the market.

Its trend-setting features don’t stop with function alone; the FGRC1244T1 is sleek and not the eyesore that many large window units appear to be. At 72 pounds, it is large, but this is to be expected with a 12,000 BTU air conditioner.

Slanted airflow features help with positive airflow, and three fan speeds keep things moving when needed, and quiet when you need subtle cooling. Frigidaire employs its Effortless™ Temperature Control to help maintain room temperatures, which also means the unit doesn’t have to work quite as hard to keep consistent.

With all these features, there’s only one drawback: the FGRC1244T1 clocks in at nearly $500, so it’s ideal for homes with larger rooms that don’t mind the higher upfront investment. However, the energy savings of this unit (especially against comparable ACs) can make up for the higher upfront costs.

If you’re looking toward the future of smart cooling appliances, or your home uses Amazon Alexa or Google Assistant, the Frigidaire FGRC1244T1 is an excellent choice to keep your tech-driven home efficient and comfortable.

5. Haier ESAQ406T Window AC

Quietest Option

Estimated Yearly Cost$44 (low setting)
Weight55 lbs
Dimensions18.1 x 21.2 x 12.4
WarrantyYes – 5 Year Limited

Unlike central air conditioners, room ACs can be loud: because their parts – motor, compressor, fan – are all in or near the space you’re cooling, you can hear them more than if they were entirely outside.

That’s not a problem, however, with the Haier ESAQ406T, our top pick for small bedrooms. This unit is quiet, performs well and doesn’t cost much more than similar units in this category (6,000 BTUs).

“At its lowest fan setting and with the cooling mode turned on, the Haier ESAQ406T runs at just 54.5 dBC,” says Wirecutter. “That’s almost 8 dB quieter than our main pick, a very obvious difference.”

Wirecutter named this model its upgrade pick for bedrooms, and Business Insider named a variation of this model one of its top window ACs available.

Haier claims that this is the quietest window AC on the market based on third-party tests, so if you’re looking for an efficient machine that won’t interrupt your work, study or sleep, this model is hands above the rest.

The ESAQ406T offers an EER of 11.2, which doesn’t qualify it to be ENERGY STAR® qualified, though a similar Haier model does meet those guidelines. However, the ultra-quiet performance of this machine, combined with its relative parts and reputation still make this one of the best picks for an efficient small bedroom AC.

The editors of Wirecutter note that “since window ACs are so tightly regulated by the Department of Energy, we’re confident that it will perform similarly to the 6,000 Btu variants of our main pick and runner-up.”

The ESAQ406T offers four modes: cool, fan, dehumidify and energy-saving mode. A 24-hour timer, remote control and sleep mode make it convenient and easy to keep on a schedule. Haier claims that it cools rooms up to 250 square feet, and ultimately, it’s ideal for small spaces that need white noise to a minimum: bedrooms, home offices and the like.

6. Arctic Wind AW6005E Energy Star Window Air Conditioner

Value for Money

Estimated Yearly Cost$50
Weight46.2 lbs
Dimensions18.6 x 15.5 x 12.7
WarrantyRequest online

If you want to ensure your room is cool enough to take on the summer heat without making a dent in your pocket, look no further than the ARCTIC AW6005E Wind 2016 Energy Star Window Air Conditioner.

It provides consumers with sustained cooling without having to spend too much upfront; positioning itself as one of the most economical options available in the current market.

The window air conditioner comes with 6000 BTU units, enabling it to cool a small room of up to 260 square-feet with relative ease. The unit also features a 12.1 EER rating and is ENERGY STAR® qualified for added efficiency.

Although the unit is affordable, its low price point should not be mistaken for sub-par quality. The window air conditioner is built with high-quality parts and lives up to consumer expectations in performance parameters.

Additionally, the Arctic AW6005E comes equipped with a remote control for added consumer feasibility, along with an energy saver function, and a digital panel laced with an LED display featuring single-touch ease of operation.

The Arctic AW6005E’s filter is completely washable, which means cleanliness will never be a concern with this product. Affixed with adjustable horizontal louvers, this unit provides comfort, as well as cooling at an exclusive price point which makes it the best budget option.

Complete with 3 different cooling options and a limited one year labor and parts warranty, the Arctic AW6005E is a cost-effective, yet reliable window air conditioner.

7. Danby DAC080BGUWDB

Value for Money

Estimated Yearly Cost$60
Weight50 lbs
Dimensions17.5 x 18.5 x 13.4
WarrantyYes – 1 year

The Danby 8,000 BTU window unit offers amazing value at an affordable price. It comes in a variety of different BTU ratings, so if 8,000 isn’t sufficient or you only need to cool a small space, then you’ve got options. No matter which one you choose, though, you can count on complete Energy Star compliance and a high EER rating (the 8,000 BTU unit has an 11.3 EER).

Most of the models on this list have come with a 6,000 BTU rating, which is only capable of cooling about 250 square feet of space. Since the Danby has an 8,000 BTU rating, it’s better for medium to large rooms that span up to 350 square feet. It’s perfect for the master bedroom or small living spaces.

The Danby window unit “is Energy Star rated and with a 24-hour programmable timer, sleep mode, and energy saver switch, this unit reduces overall operating costs and saves on your monthly hydro bills.”

Sleep mode prevents the room from overcooling overnight while the Energy Saver switche cycles the fan on and off to reduce overall energy consumption.

One of the coolest features of the Danby is the Follow Me function. This allows the remote control to act as a transportable thermostat so that the unit can more precisely alter temperatures based on your location in the room. If you prefer to control the unit without a remote, the electronic control panel is simple to use and backlit for easy viewing.

The only complaint about the Danby window unit is that it’s a bit awkward to install, especially for homeowners with upright windows. Part of this is because of the 50+ pound design, but another reason is the placement of the screw holes on the unit.

Tips for Further Reducing Your Energy Costs

While operating an energy efficient window AC is a great start, there are other things you can do to reduce your energy use and help your unit perform at an optimal level.

energy-savings listFirst, try to keep your thermostat as high as comfortably possible. Although this is easier said than done, the difference in temperature between the inside and outside environments will determine how hard your AC has to work.

A small temperature difference of just a few degrees will make it easier for your air conditioner to maintain a good working level, but keeping your room extremely cool while its cool outside will make it work harder.

Next, try to keep your air conditioner’s filters as clean as possible. You may have to replace them every few months, depending on how often it’s used, but you can clean them often to keep the air circulation going strong.

The Department of Energy estimates that not cleaning and replacing your filters appropriately can cost you between 5 and 15 percent more in energy costs. has an excellent article on clearing smoke in the home.

Finally, when you install your air conditioner, do your best to seal and plug any air leaks in the window and installation kit. Often, you’ll need to use duct tape or another adhesive to really seal all the leaks. Even great window installation kits are still made to fit multiple sizes, so they won’t be “perfect” for your window without a little extra work on your part.

Extra Steps to Help with Indoor Temps

Installing and using your AC properly goes a long way, but you can also reduce the temperature of your rooms to help keep your energy use lower. Some things include:

  • using table or portable fans to increase air circulation and ventilation
  • using ceiling fans to increase ventilation
  • using high-efficiency sun-blocking window curtains and shades
  • avoid using high-heat appliances like stoves, ovens and dryers during warm times of day

To learn more about reducing your home’s energy consumption, visit Sustainability at Harvard or

People Also Ask (FAQs)

Are Window AC Units Efficient Compared With Other Types Of ACs?

Window AC units fall right towards the end of the air conditioner efficiency spectrum – being less efficient than central air conditioning systems and split system air conditioners. However, the high upfront cost of purchasing and installing central and split systems work in the favor of window units.

How Many Watts Do These Air Conditioners Pull?

Air conditioners of different type require various watt ranges, depending upon their power and build. Window ACs fare the lowest, ranging from 1000 watts to 1750 watts.

What Voltage Do They Usually Run On?

Smaller window AC units usually run on 110-120-volt service, whereas some larger ones may require 208-240 volt.

Does the highest EER mean the most energy savings?

While EER is a good parameter to judge the energy efficiency of an air conditioner, it doesn’t always translate to the highest energy savings. There are several other factors that contribute such as the set temperature point, the condition of your air duct, and maintenance intervals to name a few.

How Much Noise Can I Expect From These Window AC’s?

Windows AC units are more inclined towards producing noise, mainly due to the fact that the loudest components of the air conditioner (the fan and the compressor) are packed in the same division and sit on the ledge. On average, a window air conditioning unit can range in the 50-80 dB range.

Can I Install The Unit Or Do I Need A Contractor?

Window air conditioners are comparatively easy to install, requiring 2 people at max to end the job in less than an hour. However, some units come with complex installations and require a professional contractor to ensure the job is undertaken safely. Unless you have prior experience in installing such units, it is best to opt for a contractor. If you buy through amazon you can also use their home services for an additional installation fee.

How Do I Install A Window Air Conditioner?

Once you’ve bought a window air conditioning unit, the first step involves setting the window kit up. After ensuring a tight seal between your room and the outer environment, secure the seal with screws. All that is left after attaching the seal is placing the unit and fastening the bracket. For a detailed understanding of the process, go through this guide.


Window air conditioning units are handy, easy to install and offer a highly economical cooling option if you’re installing them in a small room.

If you are looking to save money after the purchase of a window air conditioning unit without compromising on the quality of the product, then your best option is the AMANA model offering excellent cooling for a 150 square-feet room at an affordable price.