There are two ways to find the most efficient air conditioners in 2020.
First, try to find models that are Energy Star Certified. This one is not a deal breaker, as some companies choose not to go for the Energy star badge or are still in the process of getting an energy star label for their product. If an Air Conditioner has the label, then it’s efficiency has been verified by the Environmental Protection Agency (EPA) in the United States and it’s therefore safe to assume it’s one of the more economical and efficient air conditioners on the market.
If the unit you’re looking into doesn’t carry the Energy Star label, the next step is to ensure the AC’s energy efficiency ratings have been independently verified by an unbiased review board.
The industry standard way of rating the efficiency of Air conditioners is to give each unit a SEER or EER rating. The higher the rating, the more efficient and economical to run the AC will be. To learn more about SEER, EER and even CEER ratings, check out our FAQ section
In our reviews below, we’ve based our rankings on industry reviews, user reviews and most importantly we have fully verified all information regarding the Energy efficiency Ratios each manufacturer claims.
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Most Efficient Air Conditioner Comparison Table
1. Senville Aura & Leto Mini Split Air Conditioner Heat Pump Series
This highly versatile series combines the ability to heat as well as cool, making it as effective in winter as it is in summer.
Both the Leto and Aura groups come in 5 models rated from 9000 btu to 36000 btu so buyers have considerable flexibility in finding one to suit their room size. The Leto is the cheaper option, whilst the Aura is the more Efficient due to it’s higher SEER rating.
The Aura has a SEER rating of 25 which is amazing. The Leto, whilst only 19 SEER – is still commendable, especially for the price. Either way, you can buy knowing that you are getting one of the most efficient air conditioners in the world right now.
Both the Leto and Aura aura are energy star certified and incorporate DC invertor technology.
The Senville’s attractive appearance allows it to blend into the most elegant décor. It is also highly durable and is backed by a 2 year parts warranty and a 7 year compressor warranty.
Whisper technology allows it to operate quietly, enabling it to be used in bedrooms even while you sleep.
Comes with an installation kit that includes a 16 foot copper line set, making installation easy and straightforward.
- Highly efficient operation
- Can heat and cool
- Attractive appearance
- Comes in a large variety of sizes
- Strong fan
- May not maintain consistent temperature in some rooms
- Some minor complaints with customer service reps
2. Pioneer Mini Split Air Conditioner Heatpump Series
Another system that combines heating and cooling, this Pioneer air conditioner comes in 4 models that vary in size from 9000 btu to 36000 btu.
The Pioneer is a very futuristic device. You can use a smart app on your phone or tablet to control all facets of this split system. This app is optional, as it also comes with an LCD remote control that provides the same functionality. This includes 4 system modes: Cooling, Heating, Dehumidification and Ventilation. Alternatively, you can opt to allow the pioneer to use its on-board computer for completely automatic operation.
Even more impressive is that this AC uses an inverter system with a variable speed compressor, which enables it to cool more efficiently than older models.
On top of all this, the Pioneer also includes a timer and a night mode that is whisper quiet and varies the temperature to match the way our body temperature changes during the night.
Another useful feature is the auto restart function, which restores the unit to its former settings when it restarts after a power failure.
It comes with a comprehensive installation kit that facilitates easy installation.
- Advanced smart features
- Heats and cools
- Can be controlled remotely via app or controller
- Easy installation
- Like most Air Cons, there are occasional reliability issues
3. Air-Con Mini Split Ductless Inverter Air Conditioner Heat Pump System
The Blue Series 3 from Air-Con is an extremely energy efficient unit that comes in 4 models, some of which have up to 22 SEER rating, making it a very eco friendly AC.
It is also Energy Star and AHRI rated. Despite its high rating, which is comparable to much more expensive devices, the unit is economically priced, making it the ideal choice for cost conscious consumers.
Like the Senville and Pioneer above, the Blue Series 3 includes the ability to both heat and cool your room and has a host of advanced features.
It can pre-heat a room or cool it quickly, thanks to its Toshiba compressor and multiple fan speed settings. A sleep mode enables the ac to operate virtually silently and also vary its temperature to match the natural changes in body temperature during sleep.
The Blue 3 also has an intelligent defrost feature and a low voltage start-up function, further ensuring that it saves on your electricity bill.
Its compact dimensions allow it to blend discreetly into any room, while a lengthy warranty assures peace of mind.
- Low price
- Advanced features
- High efficiency AC
- Compact size
- Heats and cools
- Like most conditioners, there are occasional maintenance issues
4. Klimaire KSIV Ductless Mini-Split Inverter Air Conditioner Heat Pump Series
The Klimaire air conditioner comes in 4 models that have efficiency ratings of up to 19 SEER. It includes an indoor unit and outdoor unit which combine to cool or heat, culminating in one of the most efficient ac systems in the world.
The KSIV has a plethora of advanced features such as Wi-Fi connectivity and an Auto Clean function that keeps the evaporator free of mildew growth.
This is a unique function to Kilmaire. If your AC doesn’t have this feature, you might want to check our page on air purifiers to combat mold and mildew to accompany your current model.
It also offers ‘Home Away freeze protection’ that prevents room temperature from falling below 46 degrees F when you are away. Meanwhile the outdoor unit has an automatic defrosting function to protect the compressor from harsh winters while a built-on pan heater ensures that the AC / heater works effective even in very cold weather.
Multiple fan speeds and a turbo function allows the KSIV to efficiently cool the hottest rooms.
Meanwhile, in sleep mode, the system goes into extremely quiet operation.
The unit also has an innovative quick-hook design that ensures that installation is a breeze.
- A plethora of innovative features
- Able to operate in the coldest or hottest weather thanks to it’s patented technology
- Comes complete with a comprehensive installation kit
- Heats and cools
- Instruction manual can be hard to understand
5. TOSOT Window Air Conditioner 2019 Model
Unlike most window units, the Tosot has a modern, minimalist design that lets it blend into the most elegant of homes.
A powerful system, it can cool the hottest rooms quickly and effectively with its unique design allowing the fan to blow in two different directions.
It is also one of the most efficient Energy Star rated air conditioners for the window.
Among the advanced and innovative features of the Tosot is a thermostat that is located on the remote control itself, which allows it to control the temperature at locations in close proximity to the user.
The Tosot comes in 3 models to accommodate different room sizes.
The Sleep mode not only activates ultra-quiet operation, it also regulates the temperature in the night to match the changes in body temperature to ensure that you have a great night’s rest.
The main perk of the new 2019 Tosot model is that if you don’t need the air-conditioning, you can also use it as a fan or a dehumidifier.
- Attractive design
- Smart remote control with thermostat
- Advanced features
- Includes Dehumidifier
- Some people may find it noisy
- Installation can be difficult
6. Koldfront WAC6002WCO Window AC and Dehumidifier Series
This high seer window ac fits discreetly into most domestic environments and is able to effectively cool spaces between 150 to 250 square feet in size.
Its compact dimensions allow it to fit into windows just 22 inches by 36 inches in size, so it can fit into the tightest spaces.
This is an Energy Star rated product that has an EER of 12, making it very energy economical to run – so you won’t lose your cool when you see your energy bill.
Among its many electricity saving functions is an energy saver mode where the fan operates for two minutes in 10 minute cycles to maintain the temperature with the ac kicking in only when the temperature exceeds the set figure.
The sleep mode allows you to rest more comfortably by adjusting the temperature by 2 degree before returning to the set temperature after six hours. Other features include a check filter warning and a dehumidifying function.
- Affordable price
- Energy saving command features
- Compact size
- Dehumidifier included
- Only one size so cannot accommodate very small or large rooms
- Can be noisy
7. Friedrich Chill CP06G10B Window Air Conditioners
Unlike most window models, the Friedrich comes in designer white and has a modern, attractive appearance that most house owners will appreciate.
With 8 different models to choose from, all with an Energy Star rating, this series beauty is more than skin deep.
You can also enjoy superior air quality thanks to the washable, microbial filters. Its energy efficiency is boosted by the Money Saver feature in which only the fan works to cool the room.
Furthermore, it has a 24-hour timer that lets you specify the times the unit should switch on and off, ensuring that it doesn’t work unnecessarily when it is not required.
An auto sweep function lets the unit cool the room more effectively.
Its elegant appearance is complemented by its installation versatility which allows it to be installed in a window or through a wall.
The Freidrich Chill is also very quiet in operation, something light sleepers will appreciate. It comes with an installation kit and anti-intrusion protection.
- Sleek, modern appearance
- Quiet, efficient operation
- Option of installing it through the wall
- Good range of smart functions
- Some issues with fans
- Price is on the high side
8. Frigidaire FFRA0511R1 5000 BTU Window-Mounted Mini-Compact Air Conditioner
The perfect choice for the budget conscious. The Frigidaire FFRA0511R1 is a basic, cheap air conditioner that simply concentrates on doing what it’s supposed to do – cool the room. This is something it can do very effectively in any space up to 150 square feet in size.
It includes mechanical rotary controls which ensures that you don’t have to deal with costly repairs further down the line. For those with cost constraints, its appeal is further boosted by its efficient operation so it won’t make a big dent on the utility bills.
Despite its low price, the Frigidaire doesn’t ignore the most important functions that users expect, such as a dehumidifier.
It is Energy Star rated and features low power start up so it doesn’t consume excess electricity when it’s first turned on.
It also has a removable, washable filter that can easily be slid out of the unit to clean so you don’t get bacteria and other contaminants in the room.
Automatic restart automatically resumes operation at the previously set temperature in the event of a power failure.
Comes with an installation kit for easy installation.
- Low price
- Simple mechanical controls, so repair costs will be low
- Simple to use, but still has the most important functions
- Includes a dehumidifier
- No frill design won’t appeal to those who want the latest tech
Energy efficiency is one of the most important factors that people take into account when selecting a good quality Conditioner. This is hardly surprising, since inefficient devices are not only damaging to the wallet but also pollute the environment more. Fortunately, the energy efficiency of air cons has improved drastically over the past decade.
A key innovation has been the widespread adoption of DC Inverter technology, not only for the compressor but sometimes also for the indoor and outdoor fans. The compressor itself has been subject to numerous refinements that have improved operational efficiency. These include the use of better design and materials for the compression chamber, changes in fan blade shape and the incorporation of a more powerful magnet.
Using refrigerant with a higher compression ratio has also yielded significant efficiency benefits.
Another major factor that has contributed to increased energy efficiency has been the ability of the latest systems to control heat transfer using innovative features such as high density fins, inner threaded pipes, and advanced evaporators and generators.
Many new devices use smart technology to bring down energy costs by operating only when necessary, resulting in increased efficiency without compromising comfort. Home owners are also able to operate their devices over the internet, allowing them to control the units from anywhere in the world. This means that the air conditioners operate only when really necessary.
Of course, even when a device is not operating it consumes electricity. New air conditioners are able to use a minimal amount of power in standby mode, leading to far superior energy savings. Despite all this new technology, however, the energy consumption of the AC can vary a great deal depending on its type.
The energy star rating is provided by a U.S. government run program and is used to identify products that meet strict energy efficiency requirements set out by the Department of Energy.
Currently, in order to qualify for an energy star rating, Conditioners must have an SEER rating of at least 14.5 and an EER of 12.0 for split units and 11 for single models.
They must also have features that enable them to conserve energy. These specifications can change over time as new technology brings increased efficiency gains.
An energy star rating is an independent, government backed certification that a product offers superior efficiency compared to other models on the market.
The products that have earned this award usually display it prominently. This certification is widely recognized, not only in the United States but also internationally, and is a sign that you can buy with confidence, knowing that you are getting a highly efficient product.
How much does it cost to run a Window Air Conditioner? Compared to a Split one?This is a very open ended question as there’s a lot of variance to consider. Generally speaking the newer the unit, the cheaper it will be to run. If your system is 10 years old or more, then it could cost twice as much as the modern equivalent.
The next thing to consider is the size of the Air Con and the type. We measure size in BTU and TON.
Related Post: Air Conditioning types and sizes
Some Examples:Window air conditioner cost
- A small size 8000 BTU Window Air conditioner will use roughly 600 watts whilst running. If the temperature outside is 95 degrees F. Running your AC for 6 hours per day will consume approximately 350 kWh, which is about $40 per month
- A Medium sized window AC rated at 12,000 BTU will use about 1500 watts of electricity. Running this unit for the same amount of time at a constant outdoor temp of 95F will cost more, but not much more. It would come in at under $50 per month
- A Large window unit rated at 20,000 BTU would be pushing the $100 per month mark
- A small split air conditioner rated at 9000 BTU would only draw 900 watts of power. Using the same parameters above – this AC would cost less than $25 per month to run
- A medium sized 14,000 BTU split unit would draw 1400 watts and would cost approx $30 per month to run
- A large sized split unit rated at 22,000 BTU would draw 2200 watts, but would still cost less than $60 per month to run
If you’re looking for the lowest watt air conditoner, then Split systems are the way to go.
What is the most economical AC system?Typically, A Split system is the best AC energy saver and the most efficient type of air con, but some window models aren’t too far behind in second place.
How much electricity does a window AC use?A Window mounted AC will use anywhere from 500 to 1300 watts to run. Depending on their size. Not bad when you compare it to a typical Central system that will use at least 3400 watts.
How much electricity does a split AC use?A Split system can use anywhere from 400 watts up to 1500 watts depending on the size. However, the more economical ductless mini-split systems will generally come in under that. It mostly depends on the BTU of the system. For example an 8000 BTU Air Con will use about 800 watts.
How to calculate the cost to operate your AC?
In order to work out how much power your system is using and how much it costs to run, you can use the following formula:
1) Find out the SEER rating and size of the Air Con. So, for example: a 15 SEER split air conditioner at 2 ton size will run at approx 14amps, 3 ton will be around 17 amps
2) Find out the Voltage of the unit. Most Split units in the US run on 240 volt electricity, whilst many window units run on 120 volts
3) Next, you must multiply the watts by the amps. So using our split ac example above, it would be: 240 (watts) X 17 (amps) = 4,080 watts
4) Then to find out the kWh – you divide the 4,080 watts by 1000, which in our example gives you 4.08 kWh of electricity usage
What size Air Conditioning unit do I need?
To simplify the process of determining what size model you require, we just look at the square footage of the room you want to cool.
- 350 and under sq ft – 8000 BTU
- 350 to 450 sq ft – 9000 BTU
- 450 to 550 sq ft – 10000 BTU
- 550 to 650 sq ft – 12000 BTU
- 650 to 750 sq ft – 14000 BTU
- 750 to 850 sq ft –16000 BTU
- 850 to 950 sq ft – 18000 BTU
- 950 to 1200 sq ft – 24000 BTU
- 1200 to 1500 sq ft – 36000 BTU
What does BTU and TON mean?
BTU stands for ‘British Thermal Unit’. It is standard measure of energy throughout the world. As an equation, 1 BTU is the amount of heat required to increase the temperature of water by 1 degree F. In Air Conditioning, we are discussing cooling, not heating though. So, in Cooling terms, 1 BTU represents the amount of heat an Air conditioner can remove from a room every hour.
A Ton represents the total cooling capacity of an AC. 1 Ton is roughly equal to 288,000 BTU, which is the amount of heat needed to melt a 1 Ton block of Ice within a 24 hour period.
Whats the difference between EER, SEER, CEER and what do they mean?
EER stands for ‘Energy Efficiency Ratio’. It represents the ratio between the amount of cooling produced (BTU) per hour and Power in Watts. Theoretically, the higher the EER, the more cheaper to run the air conditioning system will be.
SEER stands for ‘Seasonal Energy Efficiency Ratio’. This is a newer term than EER. In 2014 the US Govt decided that simply measuring in EER was not sufficient as it doesn’t take into account seasonal variances in temperature. Where EER is calculated at a flat 95°F, SEER uses a range of temperatures from 65°F to 104°F and also runs 3 separate tests using a variety of humid and dry conditions in order to better reflect real world performance.
CEER stands for ‘Combined Energy Efficiency Ratio’ and is basically the same as EER. However it is solely used when rating Window Air Conditioners only. The only other difference from EER is that CEER rates the energy used when it I in standby mode as well as when the AC is fully turned on.
Is a higher or lower EER more economical?Or another way to put it: What is a good eer rating? In all cases a higher EER rating is more economical.
How do you calculate EER?EER is calculated by taking the BTU rating of the AC divided by the wattage. So, for example: A 12000 BTU AC that consumes 1400 watts of power = 8.6 EER Rating. The higher this number, the more efficient the Air Con.
What is more important, SEER or EER?SEER is essentially an updated and more accurate recording of how much energy an Air Conditioner is using in real world scenarios. So if possible, you should always go by the SEER number over the EER number.
How do you read the Energy Guide Label?
Do Efficient Air Conditioners run longer?Most home appliances are constantly improving. High SEER AC’s are designed to be fully switched on and running for longer periods than old AC’s. However, they usually only run at the lowest speed settings and have been optimized to use very little power when running constantly at these low speeds. It is far more economical to work this way, than constantly switching on (at full blast) and off again to maintain temperature.
Do Air Conditioners lose efficiency over time?There are many reasons why they might lose efficiency over time. Some of the reasons include: Leaks and cracks in the system, low refrigerant levels, dirty evaporator coils, blockages and general dust and dirt build up.
What is cheaper to run, Fans or AC?Fans are much cheaper to run. ACs require a lot more power to run the compressor (the bit that makes the air cold). If you’re looking to save money on air conditioning, then adding a ceiling fan to your room can allow you to raise the AC’s thermostat by as much as 5 degrees whilst still maintaining a cool temperature.
What is Energy Saver Mode?Energy saver mode helps make ACs more economical by automatically switching off the fans (exhaust and circulation) when the compressor turns off. Fans don’t use a lot of electricity, especially when compared to the compressor – but every little bit helps!
Whats the most economical temperature to set my Air Conditioner?According to scientific studies, 78°F or 26°C is the perfect temperature setting for your device. Obviously on really hot days, this might not be possible, but rest assured it does make a huge difference. Just 5 degrees cooler at 73°F can increase your AC electricity usage by a much as 40 percent!
While attempting to explain how to make ac more economical to run, we need to look at a variety of factors. Choosing a low watt model is an important first step in reducing your air conditioning costs, you can also realize significant gains by utilizing the following tips: