April 14, 2022
Open Window in Arlington Heights, IL

Keeping your home cooled throughout the summer can add up to a lot of money. Obviously, the more frequently your air conditioner runs, the more money you’ll spend. As a result, many people attempt to cut back on their energy use by turning off their air conditioning at night and opening their windows to help keep the home cool. Still, the question is whether or not this is actually an effective option for saving money on your cooling costs. Unfortunately, there really isn’t a straightforward answer as it depends largely on the local climate. With this in mind, let’s look at the numbers to see whether opening your windows at night is worth it.

Calculating Energy Savings

There is no doubt that running your air conditioner less frequently will reduce your energy costs. However, the amount you can save by turning off your AC at night may be less than you think. Studies have shown that if the air conditioning is turned on all the time, approximately one-third of the total energy use occurs between midnight and noon, with the remaining two-thirds being used during the peak daytime hours. This makes sense since the afternoon and evening tend to be much warmer.

This means that shutting off your air conditioning during the night could potentially reduce your energy usage by as much as 33%. However, the reality is that you generally won’t enjoy nearly this amount of savings, especially if you live in a hotter or more humid climate. In fact, opening your windows at night could actually end up costing you more money in the long run.

If you live in an area that generally experiences mild summer evenings, opening your windows at night can be a good option. However, if the outdoor temperature is warmer than the temperature inside your home, opening your windows will actually end up heating the house instead of cooling it. In this case, your AC will have to work harder to bring the temperature back down once you turn it back on. This added load on your AC system could end up negating any energy you saved by turning the system off at night.

The Humidity Factor

The outdoor temperature isn’t the only important factor in the equation. In fact, humidity can be an even more important factor if you live in an area that experiences very humid summers. This is because your air conditioner doesn’t just cool the air but also works to remove humidity. The more humid the air is inside the home, the harder your air conditioner will have to work to remove it.

By opening your windows at night, you’ll end up drastically raising the humidity inside the home. This humid air then soaks into your carpet, walls, and furniture. As a result, your AC will have to work overtime once it comes back on in order to remove the excess humidity and cool the home.

One study showed that shutting off the AC at night reduced energy usage by approximately 30%. However, due to the excess humidity that built up from keeping the windows open, daytime energy usage increased by more than 20%. The result was only a very minimal energy savings from keeping the windows open, as well as decreased indoor comfort due to the high humidity levels.

Based on these numbers, most experts agree that it is usually best to keep the home closed tight and the AC running all summer long until things finally begin to cool off in the fall. Still, if you do insist on shutting off your AC at night, using a fan to keep you cool is usually a more effective option than opening your windows.

Expert Air Conditioning and Heating Services

At IBBOTSON Heating & Air Conditioning Co., we have been providing professional HVAC services to customers in Arlington Heights, IL for more than 60 years. No matter what type of heating or cooling services you need, our team can handle it. Our NATE-certified HVAC technicians specialize in new furnace and AC installations. We also offer maintenance and repair services for all makes and models of furnaces, air conditioners, and other equipment. If you’re looking for ways to improve your home’s indoor air quality, we can help with that as well. We offer air quality testing services and also a range of indoor air quality solutions such as whole-home air filtration systems. Give the professionals at IBBOTSON Heating & Air Conditioning Co. a call today to schedule an appointment today!

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