A window AC unit uses between 500 to 1,500 watts of electricity. A medium size window uses 900 watts of electricity. Using this AC for 8 hours will consume about 200 kilowatt-hours of electricity each month.
By comparison, AC Window Units use approximately 500 to 1,500 watts of electricity. Keep in mind that it takes more than one AC window unit to cool a home. You'll need one for each room of the house you want to reduce the temperature. Here's an ice cube for your glass!
The cost to run a window air conditioner is $0.06 to $0.88 per hour at $0.13 kWh. Unit size, location, hourly usage, and EER will impact the actual average cost. Formula to calculate an accurate estimate: Watts * (hours used) / 1,000 * (Local kWh) = daily cost of running a window unit.
Based on that estimated range, you're looking at anywhere from $30 to $75 a month to run one window unit alone—and possibly even more if you live in an area with higher-than-average electricity costs. Keep in mind: Window AC units are designed to cool a small area only.
Cooling yourself with a fan vs. an air conditioner is significantly more energy efficient and cheaper. Fans use around 1% of the electricity consumed by air conditioners. You could leave a fan running for 24 hours and still use less energy than 15 minutes of air conditioning.
In fact, they can run for years if they are properly maintained. However, leaving a window AC unit running nonstop could reduce its overall efficiency and lifespan if not used smartly.
Cons to Keeping Fan Continuously Running:
It could cost you hundreds of dollars a year. The average unit has a 500 watt fan, which uses almost as much energy over the course of the year as a refrigerator, resulting in a $50/month bill.
In general, wall and window air conditioning units with smaller capacities can typically run for up to eight hours at a time before they need to rest. Larger wall and window units have a longer running time of around 10 to 12 hours, depending on their cooling power.
Leaving your air conditioning unit running all day won't typically cause damage to the unit itself, but it can strain the system and result in costly energy bills.
How Much Electricity Does a Ceiling Fan Use? Ceiling fans come in a variety of wattages, but a standard 48-inch model uses about 75 watts per hour on average. This would cost you about $0.01 per hour, or $6 per month if you leave your ceiling fan on 24/7 all month.
The recommended rule of thumb for summertime is to set the temperature to 78 degrees Fahrenheit when you're home and higher when you're away. In general, set it to 82 degrees Fahrenheit when you're asleep and 85 degrees Fahrenheit when you're away.
Window AC units last between 5 and 15 years, and a quality one will last 10 to 15 years on average or even up to 20 with regular maintenance. Of course, it's challenging to guarantee any appliance's lifespan, but you can get a general idea by looking at customer reviews.
Air conditioner usage varies based on the size of your AC. However, generally speaking, a central air conditioner will consume between 3000 and 3500 watts per hour. While window units use between 900 and 1440 watts per hour, portable units consume between 2900 and 4100.
Heating and cooling: 45-50%
The largest electricity consumer in the average household is your heating and cooling appliance. By a long shot. Central air conditioners and heaters use tons of energy in order to keep your home set to the right temperature.
During the hot summer months, one effective way to increase the energy efficiency of your window air conditioner is by utilizing curtains or blinds to block sunlight. This simple yet effective method can help keep your room cool and reduce the strain on your AC unit.
If you're looking for the most affordable way to cool an entire house over a long period of time, then central air will be more cost-effective. But when it comes to cooling down a couple of rooms or one floor, a window unit may be the cheaper option, with both a lower cost to install and less energy used to run.
EnergySage estimates that a typical window unit costs roughly $320 (CAD 428) per year to run in areas with a 5-month hot season. Therefore, running a window AC will likely add around $27 (CAD 36) on average to your monthly energy bill.
As it turns out, the most efficient way to keep your home cool and the bills low is to leave the AC running—ideally, with the temperature turned up toward the upper 70s.
Best AC Temperature Settings While You Are Home
As you consider the most comfortable room temperature for your lifestyle and family, keep in mind that for each degree that you set your thermostat above 72 degrees, you can save up to 3% on your energy bill.
The short answer is yes, it's more cost-effective to keep your air conditioner on all day. However, don't take this as a green light to crank it up to the max 24/7! There's a smart way to go about it, which we'll delve into in a moment. So, why is it cheaper to leave your AC on?
Allowing your air conditioner to rest is an excellent way to extend its life and ensure it operates efficiently throughout the years. Air conditioners, like homeowners, require rest in order to recover and perform optimally.
When You Run Your AC All Day, Temperature Is Everything. Yes, we have said that it is usually cheaper to keep your air conditioner on all day, but this is only true if you have it set to the right temperature. This method works when you keep it at a higher temperature (albeit lower than however hot it is outside).
Keeping your fan on AUTO is the most energy-efficient option. The fan only runs when the system is on and not continuously. There is better dehumidification in your home during the summer months. When your fan is set to AUTO, moisture from cold cooling coils can drip and be drained outside.
Thanks to the cooling properties of ceiling fans, you can help to reduce your monthly energy costs. Most central air conditioning systems cost around 43 cents per hour when they're on, which can really add up over time. On the other hand, a ceiling fan typically costs a paltry one penny to run per hour.
The average cost per kWh in the US is currently $0.11, according to the Energy Information Administration (EIA). This means an AC unit could cost you from $5.17 to $5.94 per day to run. Or about $155-$178 per month you're running it.