When you’re shopping for air conditioning in Charleston, you want a system that not only cools your entire home, but does so efficiently. Differences in efficiency between AC units can mean hundreds of dollars’ worth of difference in operation costs. When comparing units, there are a few different ways to measure system efficiency, but SEER is the most accurate rating for efficiency performance on a seasonal basis. SEER stands for seasonal energy efficiency ratio, and understanding how it’s measured and its impact isn’t too difficult.
The SEER Formula
The SEER formula starts with the British thermal unit (BTU), which is a way of measuring the cooling performance of a unit. For example, a particular AC unit might deliver 5000 BTU per hour. That number is then multiplied by the number of hours the unit operates each day, and then again by the number of days in a cooling season. Once you arrive at this very large number, you will divide it by the amount of electricity required to run the unit over that same time period. A higher SEER rating means a more efficient unit.
Since January 2006, all air conditioners sold in the United States must have a SEER of at least 13, though, if you own a unit older than that it may have a lower rating. Minimum standards are only going to rise in the coming years; the US Department of Energy has already set elevated standards to be imposed in 2015.
Installing an AC unit with a high SEER rating is good for more than simply meeting regulations, you can also save money. You can get a good estimate of just how much you could save in energy costs by looking at the SEER rating of your old and new units. By dividing the upgraded SEER rating by the older model’s lower rating, you will be left with the percentage of energy your new unit will consume compared to the old. So, if dividing the numbers leaves you with .78, your new system will only use 78% of the energy your old system used, which means energy savings of 22%. So when you’re shopping for air conditioning in Charleston, be sure to choose the highest SEER rating you can find.