What is SEER? Exploring the Seasonal Energy Efficiency Ratio
We compare modern HVAC and AC units using efficiency ratio systems - just like cars. A Seasonal Energy Efficiency Ratio (SEER) is the most commonly used standard for rating AC units. With a SEER ratio, you can usually tell at a glance how much energy can be saved over older or less efficient units when running in the same climate and conditions. Here’s a guide to SEER:
What is SEER?
A SEER is a ratio between how much cooling energy (in BTUs or British thermal units) the AC can output from a single Wh of electricity.
For example, let’s say an AC with a SEER of 13 can deliver 5,000 BTU/h. If it runs for 1,000 hours during a season (about 8 hours over 125 days, which isn’t wholly uncommon in hotter climates), it will deliver 5 million BTUs over the season. The SEER can then be used to calculate energy costs required: 5,000,000 / 13 = 384,615 Wh/year.
You can also effectively calculate how much energy an AC needs to run by dividing its cooling capacity (in BTU/h) by its SEER rating. SEER rarely considers regional climate variations but is calculated using a complex formula with variable outdoor temperatures.
If all the numbers are confusing, don’t worry. The basic idea is that a higher SEER rating on an AC unit means that it requires less electricity to run for the same duration. For example, an HVAC with a SEER of 20 is about 35% more energy-efficient than a unit with a 13 rating.
What is the best SEER rating?
Modern technology and manufacturing efforts have significantly improved air conditioning capacity, cost ratios, and energy efficiency. While units in the 20th century often don’t get over 10 SEER, current HVACs rank anywhere between 13 and 27 SEER.
The minimum SEER value required for new units in the United States is 13 in most states and 14 in the Southwest and Southeast.
A SEER of 13 is still miles ahead of the usual 8 or 9 rating old appliances often have and is a solid baseline for new units. Systems with higher SEER usually come with a few caveats, such as higher upfront and installation costs or specific requirements for the efficiency to have meaning. Just as a car can’t get the most miles per gallon when stuck in traffic, a high-SEER AC unit doesn’t always run at full energy efficiency.
What to look for in new units?
When buying a new AC unit (and it’s probably a good idea to do so if your existing unit is over a decade old), anything over 14 SEER will present significant savings compared to baseline models. More efficient units also come with additional features, such as two-stage or variable compressors, to better control the power output and maintain a higher comfort level.
Contact a local HVAC service for the best advice on SEER ratings and AC efficiency based on the local climate and weather conditions.
Stud Air Conditioning is a full-service installation, maintenance, and repair HVAC company serving Broward, Miami-Dade, West Palm Beach, and Port St. Lucie counties. Call us when you need help with your heating or cooling needs at (954)324-2905. We can help!
