If you are in the market for a new air-conditioner this season, you've either heard or will hear the term SEER rating. So what does that mean?
In short SEER stands for Seasonal Energy Efficiency Rating. Basically the higher the SEER the cheaper it is to run, but is it worth it? The higher the rating the less electricity your unit will consume, but it will cost more to purchase.
In short SEER stands for Seasonal Energy Efficiency Rating. Basically the higher the SEER the cheaper it is to run, but is it worth it? The higher the rating the less electricity your unit will consume, but it will cost more to purchase.
Lets take a look at how much a 15 SEER unit will cost to operate VS a 13 SEER unit.
To figure this out we will need a few things. The size of the unit in BTU's or tonnes, the cost of electricity per Kwh and an idea of how long it will run. Lets face it the most efficient air-conditioner is one that doesn't turn on.
So get your pencil and lets get started.
First step is to take the size of the unit, i'll use a 3 tonne unit in this example. To convert tonnes to BTU's simply multiply the tonnes by 12,000. A 3 tonne unit would be 36,000 BTU's.
To figure this out we will need a few things. The size of the unit in BTU's or tonnes, the cost of electricity per Kwh and an idea of how long it will run. Lets face it the most efficient air-conditioner is one that doesn't turn on.
So get your pencil and lets get started.
First step is to take the size of the unit, i'll use a 3 tonne unit in this example. To convert tonnes to BTU's simply multiply the tonnes by 12,000. A 3 tonne unit would be 36,000 BTU's.
Next divide the BTU's by the SEER rating. This will tell you how many watts the unit will consume per hour. 36,000 divided by 15 SEER is 2400 watts.
Convert that to Kwh by dividing by 1000. So, a three tonne air-conditioner will consume 2.4 watts per hour or 2.4 Kwh.
Next we need to determine the cost per Kwh this can be tricky due to on and off peak rates so to make the math easier we'll just use the peak rate.
Lets assume that your air-conditioner will run on average for 7hrs a day for 30 days a month and for three months. That works out to 630 hours of runtime.
Now simply multiply the cost/Kwh ($.14 as off Jan. 2015 in Ontario) by the runtime and thats what you will pay to use your A/C.
Now compare the price of both units against the cost to run each unit and see which is worth it.
Convert that to Kwh by dividing by 1000. So, a three tonne air-conditioner will consume 2.4 watts per hour or 2.4 Kwh.
Next we need to determine the cost per Kwh this can be tricky due to on and off peak rates so to make the math easier we'll just use the peak rate.
Lets assume that your air-conditioner will run on average for 7hrs a day for 30 days a month and for three months. That works out to 630 hours of runtime.
Now simply multiply the cost/Kwh ($.14 as off Jan. 2015 in Ontario) by the runtime and thats what you will pay to use your A/C.
Now compare the price of both units against the cost to run each unit and see which is worth it.
RECAP
36,000 (BTU's) / 15 (SEER) = 2400
2400/1000 = 2.4 Kwh
630 (hours) X 2.4 (kwh) = 1512 (consumption/season)
1512 (kwh) x .14 = $211.00
36,000 (BTU's) / 15 (SEER) = 2400
2400/1000 = 2.4 Kwh
630 (hours) X 2.4 (kwh) = 1512 (consumption/season)
1512 (kwh) x .14 = $211.00
or
36,000 / 13 = 2769
2769 / 1000 = 2.77
630 X 2.77 = 1745
1745 x .14 = $244.00
2769 / 1000 = 2.77
630 X 2.77 = 1745
1745 x .14 = $244.00
Therefore, assuming your A/C lasts 15 years you will save $495.00 using a 15 SEER unit.
Thanks for reading ;
Ian Stringer.