For owners of Air Conditioners, knowing the power consumption of AC is essential. To help you find the same, we have written an information rich blog below, containing information on how you can find out the power consumption of your AC and what affects it in the first place.

By understanding the power consumption of AC, you can save on electricity bills or even decide whether or not your device needs an upgrade. If you are looking to purchase a new air conditioner, or need to update an older model, read our blog on the Best 5 star ac in India.

How to calculate the power consumption of AC?

Every device these days comes with a power consumption label published by ISEER. If you look closely at this label, you will notice that it has an indication for the annual power consumption of your AC.

If you have an older AC model and wish calculate it’s energy consumption you can utilize an alternate method to calculate consumption on your own. Prior to calculation, you should also understand the concept of Kilowatt hour and Units of electricity consumed by a device.

How to Calculate Power Consumption of AC manually:

Before calculating the power consumption by your AC you must know the wattage of your AC, along with daily operational hours and electricity tariff. 1 Kilowatt an hour is an idication of the amount of energy consumed by the device.

For example, if a device utilizes 70 watt power and is running for 70 hours, it will utilize 70 watt x 70 hours = 4900 watt hours = 4.9 kWh of electricity = 4.9 units.

In AC’s you can take the following as a safe assumption –

  • 1 tonne AC = 1000 watts
  • 1.5 tonne AC = 1,500 watts
  • 2 tonne AC = 2000 watts
  • 3 tonne AC = 3000 watts

Using the above information you can calculate the power consumption of your AC.

What affects AC power consumption?

Nine factors influence how much energy is used in air conditioning.

For many businesses, the quantity of energy used in air conditioning is critical, thus it’s crucial to understand the elements that influence this consumption. Below, we’ll go over some of the most essential elements and tips for lowering these systems’ energy expenses.

Most buildings’ air conditioning systems require a significant amount of electricity. We’ll go over the most frequent factors that influence energy use and how to reduce it in this article.

The following are some of the most important factors:

1. The size of the thermal load

The thermal load is the amount of heat energy removed from a room by an air conditioning system to maintain the desired temperature and relative humidity. The following are the primary factors that influence the thermal load:

  • The passage of heat through walls and ceilings is a common occurrence.
  • The occupants of the room produce both sensible and latent heat.
  • Leaks of outside air
  • Electrical and electronic machines dissipate heat energy.
  • The sun’s heat is transferred through windows and skylights, providing illumination.
  • Conditioning of the outdoor air supply.

What can I do to lower the temperature?

The thermal load is highly dependent on the characteristics of the space being regulated; nonetheless, some things can be done to lessen it and lower air conditioning energy usage, such as: 

  • Improve ceiling and wall thermal insulation.
  • Use low-heat-transmission windows or window films.
  • Do not use more outside air than is required. Do not turn on equipment that is not in use.
  • Because lights contribute to heat load, avoid overlit environments using lighting management.
  • When the sun shines directly on the windows, include automatic motorized blinds in the lighting control system to prevent heat and glare.
  • Reduce the influx of hot and humid air from outside by using air curtains on open doors.
  • It saves energy by shifting the heat load from day to night using thermal storage materials.

2. Air cooling equipment efficiency

Air conditioning equipment is a heat pump that uses mechanical work to remove energy from the area that needs to be conditioned and transfer it to the outside.

What should I do to reduce my air conditioning energy consumption?

When purchasing the best inverter AC in India, evaluate their energy consumption in addition to the initial price and choose the one with the lowest total operating costs. In general, the most efficient equipment has the lowest overall expenses (considering initial investment, energy costs, maintenance costs, and disposal costs).

3. The outside temperature is really hot

The higher the energy consumption of the air conditioning system on a hot day is obvious. This is because high temperatures not only increase the requirement for cooling but also reduce the equipment’s efficiency.

What can I do to mitigate the effects of the hot weather outside?

There is no control over the outer temperature, which is solely determined by the outside climate. Evaporative cooling systems can be installed in air-cooled equipment, such as package units and air-cooled chillers, to lower the dry bulb temperature by evaporating water.

4. The temperature in the room

Low indoor temperature requires a lot of energy for air conditioning. A low temperature in the enclosures not only necessitates more cooling capacity but also reduces the efficiency of the air conditioning system. Low-temperature operation frequently causes occupant dissatisfaction and complaints.

Comfort temperature is influenced by several factors including:

  • Humidity relative (must be between 30 and 60 percent for comfort conditions)
  • Rate of metabolism
  • Clothing/Airspeed

5. Air conditioning equipment maintenance

Air conditioning maintenance takes a lot of energy.

In the case of air conditioning, poor maintenance results in higher energy usage. To transmit heat efficiently, air conditioning units must have as clean a surface as feasible. They should also use the manufacturer’s specified refrigerant charge and have all mechanical components working properly.

Any non-optimal condition will push the machine to use more energy in the air conditioning while also preventing it from providing enough comfort.

6. Deficiencies in Air Conditioning System

A system with poor control will consume more energy when it comes to air conditioning. Uncomfortable situations might also result from a lack of control. To ensure comfortable conditions and effective energy consumption, quality control systems must be used and installed correctly.

7. Appropriate air conditioning unit sizing

Because there is a frequent assumption that the larger an air conditioning unit is, the better it will perform, it is possible to locate air conditioning systems with more capacity than is required. Another disadvantage is the inability to adjust relative humidity and the consequent lack of comfort.

A drive with a larger capacity than required usually has other consequences, such as:

  • They need a larger electrical connection.
  • They have a higher amount of noise.
  • The ignition cycles are short, which might lead to issues with control. Poor humidity control causes foul odors.

8. Duct leaks energy in the air conditioning leaks in ducts

In ideal conditions, the ducts that transport the air conditioning do not contemplate leaks. The reality is that the vast majority of ducts have a level of leakage that ranges between 10% and 30%. This means that only 70 to 90% of the airflow reaches its intended destination and performs its function of air conditioning. Leaks in the air conditioning system resulting in higher energy usage and should be avoided.

9. Inadequate water flow balance, insufficient air conditioning, and insufficient energy balance 

Chiller water air conditioning equipment must be carefully balanced. Inadequate balance results in not just poor comfort but also increased energy use. When the water flow in the real air units exceeds the design, the pump consumes more energy and the return temperature is low, causing the chiller to operate in inefficient and energy-intensive conditions. Greater pumping causes more friction in the pipes, which raises the water temperature.

How to reduce power consumption of AC?

The consumption of an air conditioner is determined by the number of KW it consumes and the amount of time you use it. We will never have it running 24 hours a day or at 18 degrees all of the time, but its use will be influenced by where you live, the orientation of your home, and how much time you spend in it. As a result, we’re going to give you some strategies to keep your power cost from skyrocketing by focusing on its use:

1. Calculate the cooling surface

To reduce air conditioning consumption, we must first determine what surface we want to cool to make the appropriate device buy. The surface to be conditioned will indicate the required power, so that cooling the area of the house takes less time and requires less force to achieve the desired temperature. This will save you money on your electricity bill as well as on the device itself.

2. Make use of drapes and blinds

If you have drapes and blinds, utilize these to keep the house cooler by allowing less direct sunlight in. To prevent heat from entering, doors and windows must also be closed. It’s pointless to have the air conditioning on if you’re not paying attention to these details.

3. Temperature should be adjusted

We’re in the middle of summer, and we have to deal with the heat; you can’t pretend your house is a refrigerator. It’s best to keep the temperature between 24 and 26 degrees Fahrenheit. It’s summer, so forget about wearing a sweater at home or sleeping under a blanket at night.

4. Switch it off while sleeping

It is recommended that you cool the room a few hours before going to bed or schedule the device to turn off in a few hours. Your metabolism is better suited to temperatures of 26 degrees or higher when you sleep.

Power Consumption of AC – FAQs

How much power does an AC use?

While most ACs provide information on how much power they use, as a rule of thumb you can assume that:

1 tonne AC = 1000 watts
1.5 tonne AC = 1,500 watts
2 tonne AC = 2000 watts
3 tonne AC = 3000 watts

You can always check the power ratings sticker on your device for a more accurate idea of how much

1 Kilowatt an hour is an idication of the amount of energy consumed by the device. Simply multiply the wattage into the hours of usage to calculate power consumption of AC. For an example on how to calculate this, read the blog above!

How to reduce Air Conditioning power use?

Before knowing how to reduce your electricity bill, you must understand what affects power consumption of AC. To do so read the blog above. Additionally remember to follow the below-mentioned tips:
1. When not in use, switch the device off.
2. Ensure that it is well-maintained.
3. Use your AC at 25 to 27 degree celsius for optimum use.


When looking to calculate power consumption of the best low power consumption AC, you must keep certain important factors in mind. These include wattage of your AC, daily operational hours and electricity tariff which can all help you discern the power consumption by your device. To know more in depth about the same, you can read our section on how you can calculate the power consumption of AC. It is essential you do all the research before buying an AC so you don’t regret your purchase later. Happy (and intelligent) shopping!