EER Rating: Most Energy Efficient Air Conditioners (Examples)

We can all agree that having the most energy-efficient air conditioner is invaluable. Nobody wants to face the summer heatwave without something to cool the house down.

About 6% of our yearly electricity bill is generated by a single device – the air conditioner.

It would make sense to get the most out of an air conditioner, right?

That’s precisely the point of an EER rating (it stands for Energy Efficiency Rating). The higher the EER rating an air conditioner has, the more energy-efficient it is.

In short, if you want to save several $100s per year on electricity, you should look for highly energy-efficient air conditioners with high EER ratings.

What is a good EER for a portable air conditioner?

The average EER rating for a portable air conditioner is 8.5. The eco-friendly portable AC can reach an EER rating 10.

Most Energy-Efficient Portable Air Conditioner: Whynter ARC-14S with 11.20 EER rating. You can see it at 1st place in the list of the best portable air conditioners.

Such energy efficiency is achieved by the dual-hose Whynter system.

Some window air conditioners can achieve an EER rating of 12+. Anything above that should be considered great energy efficiency.

Most Energy-Efficient Window Air Conditioner: Della 048-TL-WAC6K with an incredible 12.2 EER rating. You can see it at 3rd place in the list of the best window air conditioners.

EER Chart With Respective AC Electricity Costs

Here is an EER chart of how much does it cost to run a 10,000 BTU air conditioner (be it a window unit, or any other).

For the yearly energy bills, we’ve taken into account that the AC unit is running 8 hours per day for 3 months with the price of 1 kWh being 13 cents:

yearly electricity costs of running a window air conditioner vs eer rating

You have air conditioners with EER 8 or EER 10 or EER 12 or even EER 14. Do you 100% need the EER 14 or would EER 10 suffice? That’s exactly what the air conditioner EER chart will try to illustrate.

What Is A Good EER Rating For An Air Conditioner?

Most manufacturers will provide the EER rating themselves. Even if they don’t, you can calculate it yourself just by knowing two metrics – the BTU number and the measure of power (how many watts of power your AC unit has).

Example: If a 10,000 BTU air conditioner is powered by 1,000 W, the EER rating is calculated as

EER = 10,000 BTU / 1,000 W = 10 EER rating

In this EER chart, we will look at how much electricity (power in W) does a small 6,000 BTU, medium 10,000, and 14,000 large portable air conditioner use. We also calculated the EER rating for each AC unit:

EER Rating For Portable Air Conditioner (Examples)

BTU:Power:EER Rating:
6,000 BTU
(Small Portable AC)
400 W15
6,000 BTU
(Small Portable AC)
500 W12
6,000 BTU
(Small Portable AC)
600 W10
6,000 BTU
(Small Portable AC)
700 W8.57
6,000 BTU
(Small Portable AC)
800 W7.5
6,000 BTU
(Small Portable AC)
1000 W6
10,000 BTU
(Medium Portable AC)
600 W16.67
10,000 BTU
(Medium Portable AC)
800 W12.50
10,000 BTU
(Medium Portable AC)
1000 W10
10,000 BTU
(Medium Portable AC)
1200 W8.33
10,000 BTU
(Medium Portable AC)
1400 W7.14
10,000 BTU
(Medium Portable AC)
1600 W6.25
14,000 BTU
(Large Portable AC)
1000 W14
14,000 BTU
(Large Portable AC)
1200 W11.67
14,000 BTU
(Large Portable AC)
1400 W10
14,000 BTU
(Large Portable AC)
1600 W8.75
14,000 BTU
(Large Portable AC)
1800 W7.78
14,000 BTU
(Large Portable AC)
2000 W7
14,000 BTU
(Large Portable AC)
2200 W6.36

Which AC Units Have The Highest EER Rating?

In the chart above, we’ve looked at the EER rating of portable air conditioners. Obviously, there are several different types of air conditioners and each of them has a rough EER rating interval.

If you check out the several air conditioners EnergyStar has highlighted here, you will notice that the highest EER rating is 14.

When you find an air conditioner with a 14 EER rating, you need to look no further as far as energy efficiency is concerned.

Another important energy-related metric that you should know about air conditioning is the SEER rating. The EER is most valuable for portable AC units while the SEER is most valuable for split-system air conditioners.

You can read our article about the air conditioner SEER rating here.

12 thoughts on “EER Rating: Most Energy Efficient Air Conditioners (Examples)”

  1. Hi! Thanks for the review. Are you endorsing LG window type aircon? Because Fujidenzo has higher EER compared to LG. It does mean that it is more energy efficient right? Thanks for your reply.

    Reply
    • Hello Jane, the higher EER rating equals to better energy efficiency, you are right. However, other factors that determine which air conditioners are the best, is their track-record, the reliability of the brand, dehumidification rate, average airflow, and so on. Based on these specs, the LG devices are usually superior to lesser-known Fujidenzo devices.

      Reply
    • Hello Randolf, it’s unclear to which specific device you’re referring to. However, if you want to compare the energy efficiency of a certain LG AC unit vs. a certain Panasonic AC unit, you can just check the EER rating. The one with higher EER rating is higher. EER rating is usually indicated on the specification sheet.

      Reply
  2. Sometimes I’ve seen EER= Wt/We
    For example 12000 BTU/hr = 3516.85 W.
    So, 3516.85W/1000W= 3.52
    Eer=3.52
    What is best EER for Split Inverter ACs?

    Reply
    • Hello Darwin, we’re not familiar with EER = Wt/We definition of EER. The result you’ve shown is quite low – most AC units have an EER rating of between 8 and 12. For split inverters, the more suitable metric is SEER; Seasonal EER. You can find split inverter AC units with 20 SEER or more.

      Reply
  3. Can you compare LG dual inverter vs Carrier X power gold 3 (Both 1.5hp). Carrier has higher EER but the unit itself is way more expensive. I’m not sure if it’s wiser to buy Carrier now or it won’t make a big difference when it comes to consumption if I get LG. We will most likely be using it almost everyday for more than 10 hours. Sometimes even the whole day. Thanks!

    Reply
    • Hello Ace, if you can share specs (EER primarily), the price of both devices, and the price of electricity in your area, we can do some calculation to decide which one makes more financial sense.

      Reply
  4. Can you review the latest Pansasonic Elite Sky Inverter? their 1HP product, shows 18.32 EER Rating. Would just like to know your thoughts

    Reply
    • Hello Keo, thank you for bringing the Elite Sky to our attention. You’re right, the 18.32 EER rating seems suspiciously high. EER rating calculation is fairly simple; EER = Capacity (in BTU) / Electrical Power (in W).

      Looking at the CS-VU9UKQ model specification sheet; the cooling capacity listed is 9000 Kj/h. That alone is a bit weird; obviously they mean 9000 BTU/hr. The unit they are using (Kj/h) is not equivalent to BTU/hr. 1 kJ/h is 0.948 BTU/hr. In fact, kilo-Joules per hour should be written as kJ/h (Kj/h is not the proper unit).

      The important part is this: the specification sheet list cooling power at 250 kW (obviously, that not kilo-Watts, it’s just Watts). So, let’s say 250W. Calculating EER from this would yield us 9000 BTU / 250 W = 36 EER. That would be out of this world; and it actually is. For the actual EER rating calculation, they appear to be using the 490 W power output. That would yield 9000 BTU / 490 W = 18.37 EER rating. Which is extraordinarily high as well.

      We have to admit, given the basic mistakes in units in the specs sheet, we can’t fully trust these numbers. Especially if they yield such a high EER rating.

      Reply
  5. Hi.
    Cooling Capacity 7000kJ/hr
    Power Input 583W
    Rated Voltage 230 V/60 Hz
    Is this energy efficient?
    Brand is Carrier.
    Window type Non Inverter.
    Thanks

    Reply
    • Hello LP, let’s calculate the EER rating. First, we need to convert 7000 kJ/hr in BTU/hr. 1 kJ = 0.947 BTU. That means that the cooling capacity is 6629 BTU/hr.

      EER = 6629 BTU/hr / 583 W = 11.37. That’s very energy-efficient. Only window units like Della and LG (#2 and #3 picks in the best window AC units list) are more efficient; they have 12+ EER rating.

      In general, if you find a window air conditioner with an EER rating above 10, that’s a good energy-efficiency. The ones with EER below 8 are electricity guzzlers.

      Reply

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