SEER is a metric for the general energy efficiency of air conditioners.
If you don’t already know what it means, don’t worry. You’ll find out here – just keep in mind that you need to understand what SEER means and what is a good SEER before you go shopping for air conditioners.
So, what does SEER mean?
SEER stands for ‘Seasonal Energy Efficiency Ratio’. It is a standard HVAC metric that will tell you how well will an air conditioner perform during the summer season (energy-wise, obviously).
While the EER rating will tell you the efficiency of an air conditioner at perfect conditions (95F), the SEER rating gives you performance efficiency during the whole summer season (65F to 104F).
How to find SEER rating on AC unit?
Every air conditioner should have a SEER rating in the list of specifications:
First, we’ll look at what does SEER rating means in the air conditioners, how much a better SEER rating AC unit can save you during the summer season and look at the SEER rating chart.
You will also find a SEER calculator. You can put in the BTU of your air conditioner and it’s SEER rating; the SEER calculator will calculate the yearly electricity cost. You can calculate yourself how much let’s say SEER 18 air conditioner would save you compared to SEER 14.
What Does SEER Rating Mean In Air Conditioners?
In air conditioners, the SEER rating is a metric that basically gives you an idea of how much cooling effect your AC unit will give you if you power it with a certain amount of electricity (power).
Example: You have a 10,000 BTU portable air conditioner. You’re going to use it for 150 days during the long hot summer, you run it 16h per day.
Let’s calculate how much energy this uses:
This particular AC unit generates 10,000 BTU every hour. How many hours are you running it? Let’s multiply 150 days with 16h per day, that’s 2,400 hours of use per year. In short, we use:
2,400h× 10,000 BTU/h = 24,000,000 BTU/year
We have to divide this number (24,000,000 BTU/year) with the SEER rating in order to get kWh.
For example, if we have an air conditioner with a SEER rating 10, we’re looking at 2,400,000 kWh. If, on the other hand, we have an air conditioner with a SEER rating 20, we’re looking at 1,200,000 kWh (half as much).
How much does that difference in SEER rating save us? Well, let’s calculate. An average price of a kilowatt-hour (kWh) in the US is 13,19 cents.
- SEER 10 electricity cost: (2,400,000 kWh x 13,19 cents)/1000 = $316,56/year
- SEER 20 electricity cost: (1,200,000 kWh x 13,19 cents)/1000 = $158,28/year
In short, you can save about $150 per year even with a medium sized 10,000 BTU portable air conditioner. That is $1,500 in 10 years.
The price of a portable air conditioner is usually below $500. However, as we’ve seen based on SEER rating, an air conditioner with a higher SEER rating can pay off quickly just by how much less electricity it costs.
SEER Rating Chart
Let’s illustrate the difference in yearly electricity costs of using SEER 12, SEER 14, SEER 16 air conditioner. Below is a SEER rating chair with yearly electricity costs. It takes into an account:
- 36,000 BTU air conditioner (3 ton AC unit).
- 1,000 operating hours per year.
- Average electricity price of 13,19 cents per kWh.
From the chart, you can see that an air conditioner with SEER 10 will cost 475$/year in electricity cost. SEER 20 air conditioner will give you exactly the same cooling effect for 237$/year because it’s that more efficient.
The difference between SEER 16 and SEER 14 is, as you can read from the graph, 42$/year. In essence, SEER 16 air conditioner is 13% more efficient than SEER 14.
What Is A Good SEER Rating?
SEER 16 is a good SEER rating for an air conditioner. Anything above that – SEER 18, SEER 20 – is great.
Only old devices made in the 80s and 90s will have a SEER 10 rating. From 2015 onward, most states have regulation in place that guarantees that all new air conditioners should have a SEER rating of at least 13 or 14 (depends on the type of air conditioner and state).
Honestly, if you’re buying an air conditioner that will last for 10 years or more, it is highly recommended to buy one with a higher SEER rating. It might cost $100 more but you will spend less energy running it which is good for your pocket and for the environment.
SEER Calculator For AC Units (What Is A Good SEER Rating?)
When looking at different air conditioners, it’s useful to know the electricity costs associated with the unit. Obviously, SEER ratings in the most important metric when choosing an energy-efficient AC unit. Knowing what is a good SEER rating of an air conditioner is essential.
You can use this calculator below to calculate the yearly electricity cost for every air conditioner. We predispose the 1,000h/year operation use and 13,19 cent per kWh to calculate the electricity bill based on BTU and SEER rating:
A good exercise is to input the BTU of an air conditioner (let’s say 20,000) and change the SEER rating. Here are the yearly electricity costs for this example for different SEER ratings:
- 12 SEER = $219,83
- 14 SEER = $188,43
- 16 SEER = $164,88
- 18 SEER = $146,56
- 20 SEER = $131,90
You can see that picking the 20 SEER air conditioner instead of 14 SEER one would save you $50+ per year. In 10 years, that’s $500. Even if the 20 SEER costs $200 more, it’s worth the price. Here are, for example, ductless mini split ACs with SEER ratings above 20. If an air conditioner has a 20+ SEER rating, that is considered a very good energy-efficient unit.
Here is another example:
What is the difference between 14 SEER and 16 SEER rating?
We can calculate how much more energy-energy efficient a 16 SEER unit is compared to 14 SEER unit. We can calculate 16/14 = 1.143; that means 16 SEER is 14.3% more efficient than 14 SEER unit.
Lets say we have a 12,000 BTU device. By using the SEER cost calculator above, we can see that:
- 14 SEER unit spends $113.05 per year.
- 16 SEER unit spends $98.93 per year.
That means the difference in electricity bill would be about $15 every year.
To answer ‘what SEER rating should air conditioner should you buy’ is very simple: Buy the one with the higher SEER rating. In 10 years, the higher price of a high SEER unit will pay for itself in saved electricity costs.
I hope this SEER calculator is helpful. If you have any problems using it, you can write to us in the comments below and we’ll look at how we might help.