In last month’s post, “How Upgrading Your AC Unit Can Help Reduce Your Power Bill & Improve Your Air Quality,” we describe SEER (Seasonal Energy Efficiency Ratio) for air conditioners and how the higher the SEER, the higher the energy efficiency of the unit. A higher SEER rating equates to lower monthly electricity bills. Deciding what the best SEER rating is for you is something our expert comfort consultants are more than happy to discuss. This article helps you understand what SEER rating is (with a bit of math – brace yourself!) so you can make the right decision when installing your new air conditioning system.
Polar Bear Air Conditioning is committed to bettering our customers’ understanding of the processes involved in air conditioning systems. We hope that by providing you with comprehensive information on air conditioning systems, you’ll have the right knowledge to make the best decision regarding the air conditioning system for your home or business.
A Brief Overview of SEER
The Seasonal Energy Efficiency Ratio (SEER) measures how much energy — and how much money — an air conditioner uses to operate over the course of one year. The SEER rating scale ranges from 13, the minimum SEER rating required from any air conditioner, to over 20. All of this data is collected so that the AC system has a simple number for consumers to compare to other systems in their hunt for the most reliable and efficient model.
Before we dive into the calculations, let’s take a moment to unpack this question: is a higher SEER rating worth it?
For many homeowners, the answer is a resounding yes! Where the cost of electricity is very high and air conditioning contributes up to 80% of energy usage the economics become very clear. As air conditioners get older they become less efficient and electricity bills can climb to more than double than when the system was new. Replacing an old AC with even a low SEER system can cut your monthly bills in half; replacing it with a high SEER system can cut monthly electricity bills even more! In essence high efficiency systems can pay for themselves in a very short period of time. Besides reducing money out of your pocket every month, a high SEER AC system will also deliver better comfort by removing more humidity and maintaining a more consistent temperature.
However, there is a catch. Air conditioners with higher SEER ratings are also more expensive upfront. It’s important to choose your new system wisely, so your monthly savings are not negated by the overall cost of the air conditioner.
In the following example, we will show you how you can compare the SEER of two AC units and see the energy savings first-hand.
What You Need:
- SEER Numbers & BTUs (the size of the system) for 2+ Comparable Units
- Approx. Cooling Season (how long the unit will run per day & how many days it will run in a season)
- Calculator (optional)
12 SEER 2-ton Air Conditioner vs. 16 SEER 2-ton Air Conditioner (24,000 BTUs per Unit)
- First, we need to determine kilowatt-hours by dividing the system BTU’s by the SEER rating:
12 SEER: 24,000 BTUs / 12 (SEER) = 2,000 kWh
16 SEER: 24,000 BTUs / 16 (SEER) = 1,500 kWh
- Now we need to calculate costs per hour (assuming $0.305 per kWh):
12 SEER: 2.000 X 30.5 cents per kWh = 61 (or $0.61 per kWh)
16 SEER: 1.500 X 30.5 cents per kWh = 45.75 (or $0.46 per kWh)
- Finally, we will compare the two units’ yearly usage savings (assuming the unit will run an average of 13 hours per day for 365 days):
13 hrs per day X 365 days = 5,110 hours per year
12 SEER: 5,110 hours X $0.61 per hour = $3,117.10 per year
16 SEER: 5,110 hours X $0.46 per hour = $2,350.60 per year
So, is a higher SEER rating worth it? In the above sample (which uses data for a homeowner in the Cayman Islands), the 16 SEER air conditioner would save the owner about $766.50 per year on the energy bill! If we apply this to the typical lifespan of the AC system (roughly 10 years if properly maintained) that would result in a total savings of $7,665 from your utility bills!
The Benefits of a Zoned Air Conditioning System
When looking to increase the overall efficiency of your central air conditioning, it is also important to consider installing a zoned system. A zoned AC system controls the output of your air conditioning depending on the temperatures set on thermostats throughout the home.
A zoned air conditioner works by utilizing dampers in the ductwork. These dampers direct the flow of air to different sections of the home, depending on thermostat settings. This is an effective way to save energy and create custom comfort levels for individual family members. Zoned HVAC systems can be set up for different rooms or areas in the home and are an excellent option for anyone looking to save energy and save money.
Moisture Control and Air Conditioning: How Does it Work?
Almost all standard air conditioners remove humidity from the air through a process called condensation. Mini split air conditioners and central air conditioning units change the threshold of relative humidity by exposing warm air to the cold evaporator coils. The ability of the system to remove humidity is critical for comfort. Systems that remove less humidity may cool the area to the set point on the thermostat, yet the space still feels sticky and clammy. Furthermore, the system doesn’t have to work as hard, using additional energy to get to a lower temperature because even though it’s a couple degrees warmer it still feels more comfortable.
The level of importance of dehumidification differs in different climates. A professional heat load calculation can be used to determine what we call the sensible heat ratio. To understand sensible heat ratio you need to understand 2 types of heat load that all systems need to remove. One is what we call sensible heat – removing sensible heat results in the temperature on the thermostat going down. The second is latent heat – removing this results in less moisture in the air. So the sensible heat ratio is the sensible heat load divided by the total heat load (both sensible and latent heat load). In humid climates latent heat load is important and high efficiency units do a great job in getting to the desired relative humidity indoors.
Moisture control is an essential aspect of maintaining a cool and comfortable home. Without the ability to dehumidify the air, an air conditioning system will struggle to lower and sustain cold indoor temperatures. It is important to note that some units with lower SEER ratings do not provide the level of humidity control that homes in the Cayman Islands require, so there’s value in speaking with an air conditioner specialist when you’re looking to upgrade your system.
Stay Cool With Polar Bear Air Conditioning
Polar Bear Air Conditioning is a leading supplier of air conditioning systems for residential and commercial applications. For over 30 years, Polar Bear has proudly served the community in providing cooling solutions for our customers.
Now that you have the calculations and a better understanding of SEER ratings and the process of condensation check out some air conditioners, and find the best unit for your money by plugging in your own numbers. Choosing the right air conditioner for your home or business is more than just “bigger is better”! Contact the expert technicians at Polar Bear Air Conditioning today for more information on SEER comparisons or the best air conditioning installations, repairs, and maintenance in Grand Cayman!