Does a Central Air Conditioner Consume a Lot of Electricity?

Ian Mutuli
Updated on
Ian Mutuli

Ian Mutuli

Founder and Managing Editor of Archute. He is also a graduate architect from The University of Nairobi, Kenya.
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The air conditioner is an integral part of the home. When making a budget for home appliances, it appears in the must-have section. Air conditioning is important because it offers your abode cooling solutions that are lasting and effective. Therefore, a central air conditioner comes in handy when you wish to cool multiple rooms at a go. Before settling on this, the main question would be, ‘How much electricity does a central air conditioner use?’

The electricity usage of an appliance influences its purchase. This is because you can estimate the amount you will pay as an electricity bill. Hence, make the decision on whether to buy or not. That said, a central ac unit consumes a lot of electricity, but it releases cool air into your environment in an instant.

How Much Electricity Does A Central Air Conditioner Use?

Central AC set up

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Electricity usage and billing are measured in kilowatt-hours (kWh). The price per kilowatt hour depends on the state that you are in.

One kilowatt hour (kWh) = 1000 watts (W)

On average, a central air conditioner uses 3000 to 4000 watts per hour. Therefore, this translates to 3kWh to 4kWh per hour. You are most likely to use your ac unit irregularly throughout the year. It will be most useful in warmer months and less in use in colder months. Thus, your electric bill is likely to be much higher in summer and lower in winter. A central ac can be used for a total of five months annually.

Factors that Affect the Amount of Electricity Central Air Conditioners Use

Central air conditioner in a home

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Several factors determine the electricity consumption of central air conditioners. They include:

1. Size

When purchasing an ac unit, it is best to consider the size of the space that you intend to cool. A small unit will be perfect for a small space because it will distribute cold air evenly throughout the room. If it is bought for a larger space, it will be overworked to maintain the room cold. Thus, consuming more power.

A larger central ac is also recommended for a large house. It will work efficiently. However, if it is used for a small space, it will cool the space quickly, leaving more moisture in the atmosphere. The humidity may promote mold growth in the long run. Furthermore, more energy will be used to power this ac.

2. Age of Air Conditioner System

Older air conditioners were developed using older technology. While they still work efficiently, they also use less electricity. However, if they are not serviced regularly, they are more likely to use much more energy to maintain the required temperature. The same goes for newer models.

3. Type Of Air Conditioner Unit

A central air conditioning system uses more wattage than the window ac unit or the mini split air conditioners. The type and model of ac will determine the wattage too. Most manufacturers advise on the wattage so that you make an informed choice.

Moreover, it is also advisable to check the SEER (Seasonal Energy Efficiency Ratio) number on the ac unit. The higher the SEER number, the more efficiently the unit will perform.

4. Energy Star Rating

Home appliances that have an Energy Star have met strict energy-efficient guidelines. The appliances save you money in electric bills and also help to protect the environment. They use 8% less energy than the newer models. For this reason, when purchasing a central air conditioner, it is best to buy one that has an Energy Star rating. The energy consumption will be reasonable.

How to Reduce a Central Air Conditioner’s Energy Consumption

Technician fixing the Central ac in an office

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We are all looking for a way to conserve energy and also reduce power consumption by our appliances. Here are several ways to decrease the energy usage of your central air conditioners.

1. Invest in The Right Size Air Conditioner

The size of the ac unit you choose for your home or office is crucial. This is because you need an ac unit that effectively delivers cool air to all rooms. A smaller central ac in a larger house will not be efficient because it will be overworked trying to keep all the rooms cool. Thus, it is vital to engage the services of professionals who understand air conditioning. They will offer expert advice on the right side of the ac system.

2. Schedule The Cooling System For Servicing

The central air conditioning systems need to undergo regular servicing. These checks ensure that everything is working just fine. The service includes checking and cleaning the air ducts, motors, and filters. Additionally, the professionals may catch a problem earlier when doing the service. If anything goes wrong with your central ac unit without noticing, the system may use more energy and increase your cooling costs.

3. Change Unit Filters Regularly

Central ac has an outdoor unit prone to dust and debris blowing its way. The dirt and debris will hurt the working mechanism of the ac unit. It will be slow and ineffective, resulting in more electricity consumption. It is, therefore, important to change and clean the filters regularly.

4. Keep Windows Closed, Especially During Warmer Months

Central ac is mainly useful during the warm seasons. During this period, you can keep your windows and doors closed to minimize the amount of hot air getting into the rooms. This is helpful because your central ac will not have to work harder to cool your home, which always results in higher energy consumption.

5. Set The System Correctly

Every cooling system has its setup. When setting up the central air conditioning system, ensure that it has been set up correctly and the right procedures followed. This is important because it avoids overcooling.

6. Install Solar Panels

Setting up a solar system in your home would help reduce electricity usage. The solar energy generated would be used to power the central air conditioning. As a result, you would pay less electricity bills and get good air conditioning at the same time.

Frequently Asked Questions on Air Conditioners And Electricity Usage

Central AC carrier outdoor unit

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1. Can A Central Air Conditioner Be Powered Using Solar panels? If So, How many?

Yes. A central ac can be powered using solar panels. Since this ac unit uses an average of 3000 to 4000 watts, you would need ten panels of 350W to stay powered. Even though ac units do not always use much electricity, you will require to install solar panels that can handle the higher usage times.

2. Which One Uses More Electricity? A Central Air Conditioner or a Window Air Conditioner?

A central ac uses more electricity than a window ac. A central ac uses an average of 3000 to 4000 watts to cool several rooms. A window air conditioner, on the other hand, uses an average of 500 to 1400 watts to release cool air into a single space.

3. Why Does My Central Air Conditioner Use So Much Power?

A central ac uses so much power because of its working mechanism. It has one that is similar to a refrigerator. The air conditioning system has a series of tubes made into coils known as the evaporator and condenser coils. It also has a compressor that transports the refrigerant throughout the ac system.

The refrigerant evaporates, releasing a gas pumped back into the compressor, expelling heat outside and delivering cool air throughout your house or office. This entire process is complex and requires a lot of energy to complete. The more the cooling output of your ac, the more electricity it consumes.

4. Is It Cheaper to Keep The Air Conditioner On or Off When It Is Not In Use?

The decision to keep the ac on or off will depend on the temperature inside and outside your house or office. If you maintain your house or office at a consistent temperature, it is cheaper to turn the ac off when it is not in use. Nevertheless, if the temperature keeps fluctuating throughout the day, it is better to keep the ac on to ensure that your home or office is comfortable.

5. Which Is Better, Central AC or Mini Splits?

Central air conditioning is better than the mini splits. This is because it can cool several rooms at the same time. However, because of the ducts and filters, it requires regular servicing. Mini-splits, on the other hand, are ductless and can be more expensive to install. Nonetheless, they require little to no maintenance.


Air conditioning systems are an integral part of your home or office. They come in handy during warm seasons when we want to cool down from the sweltering heat. Generally speaking, they help maintain a cool environment at home or work areas. The central air conditioner cools down several rooms at the same time. It is ideal for large spaces. Before installing one, it is important to know its energy consumption so that you estimate the cost of operating this home appliance.

Ian Mutuli

About the author

Ian Mutuli

Founder and Managing Editor of Archute. He is also a graduate architect from The University of Nairobi, Kenya.
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