April 19, 2022
Open Window in Drexel Hill, PA

The sweltering summer temperatures in most of Pennsylvania make having air conditioning a must. However, leaving your air conditioning running day and night throughout the entire summer can result in huge electricity costs. If you’re like many people, you may attempt to reduce these costs by turning off the AC and opening your windows at night. You may be surprised to learn that this practice has much less of an impact than you think, and here are the reasons why.

Day and Nighttime Energy Usage

To determine how much you can reduce your energy bills, it’s first important to look at how much energy your AC uses during the day and at night. Studies have shown that if an air conditioner is left turned on 24 hours a day, approximately two-thirds of its total energy consumption occurs between noon and midnight. Theoretically, this should mean that shutting off the AC from midnight to noon will reduce your cooling costs by around one-third. Unfortunately, the reality is usually different unless you live in a dry, mild climate.

Calculating Actual Energy Savings

The summers in the Philadelphia area tend to be quite hot and humid, and this has a major impact on your overall cooling costs. It is probably fairly obvious that air conditioners have to work much harder in hotter temperatures. However, many people aren’t aware that humidity also plays a huge role in how efficiently and effectively an air conditioner works. This is because air conditioners don’t just cool the air, they also work to remove excess humidity. As a result, the unit will have to run more frequently and for longer periods when the humidity is high.

In theory, as long as the outdoor temperature is below the temperature in your home, then opening your windows at night will reduce your energy usage and still keep your house cool. However, the fact is that this rarely happens in Pennsylvania. During the hottest parts of the year, it is not uncommon for outdoor temperatures to remain well into the mid-70s or above until at least midnight. This means that opening your windows before going to bed will usually end up making your home hotter, which could result in your air conditioner having to work harder when you turn it back on in the morning.

Numerous studies have been performed on this subject to compare the differences in energy consumption between opening the windows and using air conditioning at night. In one study, researchers saw an average of a 30% decrease in electricity consumption by turning off the AC at night. However, when windows were also opened, the increased temperature and humidity inside the house resulted in the air conditioner using more than 20% extra energy during the day. While this wasn’t enough to completely offset the savings from turning the AC off at night, the difference between the two was still very minimal.

Of course, energy costs are really only one thing that you should consider as your overall comfort is also important. The fact that nighttime temperatures in Drexel Hill and the Philadelphia area are still quite high until after midnight means that opening your windows will often make you hotter. For this reason, it is generally always the best option to keep your home closed tight and the AC running moderately all summer until the temperatures finally start to truly cool off in the fall.

Get Professional AC Maintenance and Services

If you are looking for ways to reduce your cooling costs during the summer, there are other options that can have as much or even more of an impact than simply turning off the AC at night. Regular maintenance of your cooling system is one of the best things you can do for its energy efficiency. At O'Brien Heating & Air Conditioning, we offer maintenance and repairs for all types of cooling equipment as well as heating systems for customers in Drexel Hill and the greater Philadelphia area. We can also replace your old air conditioner with a new, much more energy-efficient model. We specialize in a wide range of other services including indoor air quality, duct cleaning, water heaters and more. Give us a call today to learn more about our services or to find other ways you can reduce your energy costs!

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