“I’ve got these two AC quotes: 3 ton 14 SEER costs $5,810 and 3 ton 18 SEER costs $7,050. Should I pick 18 SEER over the 14 SEER unit? Can the energy savings justify this $1,240 cost difference?”
This is a good example of the 14 SEER vs 18 SEER unit dilemma. We will show you exactly how to calculate the energy savings, and see if the more expensive 18 SEER unit is worth the extra cost (if the energy savings will pay back the difference).
To help you out with the calculations we will showcase below, we have prepared these 2 very easy tools to use:
- 14 SEER vs 18 SEER Energy Saving Calculator. Here you insert the AC tonnage (Example: 3 ton), and electricity rates (Example: $0.15/kWh), and the calculator will automatically determine the 1-year, 10-year, and 20-years energy efficiency savings of 18 SEER unit over 14 SEER unit.
- 14 SEER vs 18 SEER Savings Chart. We have done the math for you and calculated 1-year, 10-year, and 20-year energy savings for 1-8 ton AC units. You can find all the results summarized in a colorful chart below.
Now, let’s solve the above example to illustrate how to calculate 14 SEER vs 18 SEER energy savings. The key difference between 14 SEER and 18 SEER air conditioners is that an 18 SEER unit is 28.57% more energy efficient than a 14 SEER unit.
We can calculate the average running wattage using the SEER rating like this:
AC Running Wattage = Tonnage × 12,000 / SEER Rating
Here are the results:
- 3-ton 14 SEER unit runs on 2,571W (average). It uses 2.471 kWh per running hour and 2,471 kWh per year (1,000 running hours). If we multiply that by the kWh price (say $0.15/kWh), we see that we use $385.71 per year. That is $3,857.14 in 10 years, and $7,714.29 in 20 years.
- 3-ton 18 SEER unit runs on 2,000W (average). It uses 2 kWh per running hour and 2,000 kWh per year (1,000 running hours). If we multiply that by the kWh price (say $0.15/kWh), we see that we use $300 per year. That is $3,000 in 10 years, and $6,000 in 20 years.
We see that by opting for 18 SEER over 14 SEER unit under these conditions, we are saving $85.71 per year. The 20-year savings are $1,714.29; more than the upfront cost difference of $1,240. In this case, we should opt for the 3-ton 18 SEER unit.
If the 20-year savings would be below, say, $1,000, it would be financially more viable to opt for the 3-ton 14 SEER unit, since the energy savings (below $1,000) don’t justify the cost difference ($1,240).
This is how to make a basic energy savings analysis. Admittedly, it does involve quite a lot of math. To help you out with this math, we have created an easy-to-use 14 SEER vs 18 SEER energy savings calculator that will make all these calculations automatically (based on AC tonnage and electricity price inputs)
Below the calculator, you will also find a chart with 1-year, 10-year, and 20-year savings for 1-8 ton AC units. Let’s use this calculator first:
14 SEER Vs 18 SEER Savings Calculator
Let’s solve 1 example to show how this online 14 SEER vs 18 SEER calculator works:
Say we are choosing between 4 ton 14 SEER and 4 ton 18 SEER unit. The electricity prices in our area are $0.12/kWh. To calculate the energy savings, just slide the 1st tonnage slider to ‘4’ and the 2nd electricity cost slider to ‘0.12’. Here is the result:
By opting for 18 SEER instead of 14 SEER unit (under these conditions), we are saving $91.43 every year. That’s $914.25 in 10-year savings, and $1,828.57 in 20-year savings.
Now, if the 18 SEER unit is by more than say $2,000 more expensive than the 14 SEER unit, you should opt for a 14 SEER unit since the 20-year savings ($1,828.57) don’t justify the higher cost.
On the other hand, if the 18 SEER unit cost say only $1,000 more than the 14 SEER unit, the financially more viable choice is the 18 SEER unit. That’s because the 20-year energy savings ($1,828.57) justify the $1,000 cost difference.
Here is the full 14 SEER vs 18 SEER savings chart for 1-8 AC units (at $0.15/kWh and 1,000 running hours per year):
14 SEER Vs 18 SEER Chart For 1-8 Ton Air Conditioners And Heat Pumps
| Unit Size (Tonnage): | 1-Year Savings ($): | 10-Year Savings ($): | 20-Year Savings ($): |
| 1 Ton | $28.57 Savings Per Year | $285.70 Per 10 Years | $571.40 Per 10 Years |
| 1.5 Ton | $42.86 Savings Per Year | $428.60 Per 10 Years | $857.10 Per 10 Years |
| 2 Ton | $57.14 Savings Per Year | $571.40 Per 10 Years | $1,285.70 Per 10 Years |
| 2.5 Ton | $71.43 Savings Per Year | $714.30 Per 10 Years | $1,428.60 Per 10 Years |
| 3 Ton | $85.71 Savings Per Year | $857.10 Per 10 Years | $1,714.30 Per 10 Years |
| 3.5 Ton | $100.00 Savings Per Year | $1,000.00 Per 10 Years | $2,000.00 Per 10 Years |
| 4 Ton | $128.57 Savings Per Year | $1,285.70 Per 10 Years | $2,285.70 Per 10 Years |
| 5 Ton | $142.86 Savings Per Year | $1,428.60 Per 10 Years | $2,857.20 Per 20 Years |
| 6 Ton | $171.43 Savings Per Year | $1,714.30 Per 10 Years | $3,428.60 Per 20 Years |
| 7 Ton | $200.00 Savings Per Year | $2,000.00 Per 10 Years | $4,000.00 Per 20 Years |
| 8 Ton | $228.57 Savings Per Year | $2,285.70 Per 10 Years | $4,571.40 Per 20 Years |
We can see that 18 SEER vs 14 SEER energy savings are quite substantial. Namely, by choosing 18 SEER unit over 14 SEER unit you can save:
- $28.57 to $228.57 per year.
- $285.70 to $2,285.70 in 10 years.
- $571.40 to $4,571.40 in 20 years.
With this analysis and the use of the chart and calculator, you are now well-equipped to calculate the 14 SEER vs 18 SEER energy savings. If you need some help, you can always use the comment section below, give us some numbers, and we can do the math for you.