How much power does an air conditioner use?

A kilowatt, or kW, measures power. A kilowatt-hour, or kWh, measures energy used over time. A unit averaging 1 kW of electrical input for one hour uses 1 kWh. Keeping those two figures separate makes the running-cost calculation much easier.

How much does an air conditioner cost per hour?

If its electrical input averages 0.8 kW, one hour at an illustrative 35 cents per kWh costs 28 cents. That is a calculation using an assumed input, not a measured cost for every 3.5 kW unit. If the app reports actual kWh, multiply that energy by the applicable rate instead.

How much does it cost to run for a day?

For a simple estimate, use:

Average electrical input in kW × hours running × electricity price per kWh.

Suppose an air conditioner averages 0.8 kW of electrical input over eight hours. It uses 6.4 kWh. At an illustrative 35 cents per kWh, that costs $2.24 in electricity.

If it averages 1.5 kW instead, the same eight hours cost $4.20. These are calculation examples, not measured costs for particular models or room sizes.

An inverter unit can change its electrical input as the room approaches the set temperature. A hot room, afternoon sun, insulation, room size and thermostat setting all affect the work required. An actual kWh reading for the session is more useful than assuming the rated input stays constant.

Find your air conditioner’s electrical input

Check the model number and manufacturer’s specifications. Look for electrical input or power consumption, and keep it separate from heating and cooling output.

When comparing new systems, use the Zoned Energy Rating Label. It gives heating and cooling information for hot, average and cold climate zones, including estimated annual electricity use under standard conditions. Compare units of a suitable size in the same climate zone.

Check the label’s climate zone for your location in the region, and compare both heating and cooling. A unit chosen for summer may also need to keep the house comfortable on a cold winter morning.

If you’re an ActewAGL customer, you can view household energy usage in My.ActewAGL (opens in a new tab). Otherwise, look for usage data in your retailer’s app or online account. If the air conditioner reports its own consumption, check whether that figure is measured or estimated. Whole-home smart-meter data includes other appliances running at the same time. Ask an electrician about suitable monitoring if you need to isolate a hardwired system.

Make the room easier to cool

Close blinds before strong sunlight reaches the windows. Keep filters clean and cool the space you are using. A fan can improve how cool you feel, which may let you choose a more comfortable thermostat setting with less air conditioning.

A review by UNSW and RMIT researchers also supports reducing heat entering buildings through solar control and suitable passive cooling. Which measures work best depends on the climate and building; the research does not promise a fixed saving for every home.

Your tariff affects the bill too. If the session crosses several pricing periods, calculate the electricity used in each period at its own rate. The existing daily supply charge is separate from the extra cost of that cooling session.

Check your model’s electrical input, your rate and the hours you run it. If the estimate is still unclear, record a few comparable sessions using suitable energy data. You will have something useful to compare before changing settings or replacing the system.

If a label estimates 600 kWh a year in your climate zone, treat that as a standardised comparison with a similarly sized model. It is not a forecast that running the unit for one day will use 600 divided by 365. Record a real session, or use a justified average input and the hours you need.

Related advice: Should I switch the aircon off when I go out? · When is off-peak electricity?

Find the rate and the next step

Our bill-reading guide (opens in a new tab) can help you find the rate for an ActewAGL running-cost calculation. If replacing gas heating is the next job, start with our heating and cooling upgrade page (opens in a new tab) and check the current eligibility and quote route. Ask the installer to confirm the system size and cold-weather performance for your home.

Compare the whole electricity plan