What it costs to run an air conditioner in each state
The table uses a medium split system drawing about 1.5 kW for five hours a day, every day. That is a summer evening of cooling or a winter evening of heating in a living area.
| State | Rate | A month | A year |
|---|---|---|---|
| TasmaniaAurora Energy | 24.75c | $56.46 | $678 |
| QueenslandEnergex | 27.97c | $63.82 | $766 |
| Victoriaaverage of five networks | 28.2c | $64.32 | $772 |
| Northern TerritoryJacana Energy | 31.68c | $72.27 | $867 |
| New South WalesAusgrid | 33.14c | $75.59 | $907 |
| Western AustraliaSynergy | 33.26c | $75.88 | $911 |
| Australian Capital TerritoryEvoenergy network | 36.95c | $84.30 | $1,012 |
| South AustraliaSA Power Networks | 41.91c | $95.61 | $1,147 |
Running costs by type and size
The cooling capacity in kW printed on the box is the heat the unit moves, not the electricity it uses. Divide capacity by the unit's efficiency and you get the input power. Modern split systems move three to four times more heat than the electricity they draw, so a 5 kW unit needs around 1.5 kW of electricity at full output. The input power is on the energy rating label and in the specifications.
| Type | Power | Cost an hour | A year |
|---|---|---|---|
| Small split system, 2.5 kW cooling | 750 W | 25c | $454 |
| Medium split system, 5 kW cooling | 1,500 W | 50c | $907 |
| Large split system, 7 kW cooling | 2,100 W | 70c | $1,270 |
| Ducted system, 14 kW cooling | 4,300 W | 142c | $2,600 |
| Portable air conditioner | 1,100 W | 36c | $665 |
The SA Government publishes its own hourly estimates, which come out in the same range: a split system for a room up to 36 m² at 69c to 93c an hour on a flat rate, and a ducted refrigerative system cooling 125 m² at $1.79 to $2.42 an hour. Evaporative coolers cost far less to run, at 44c to 59c an hour for a ducted system including water.
Is an air conditioner cheaper than a heater?
Almost always, yes. A fan heater, oil column or panel heater turns each unit of electricity into one unit of heat. A reverse cycle air conditioner moves heat in from outside, delivering three to six units of heat for the same electricity. The SA Government estimates a small reverse cycle unit costs 10c to 14c an hour to heat a 12 m² room, against 46c to 62c for a panel heater and 92c to $1.25 for a portable heater.
| Heater | Cost an hour |
|---|---|
| Small reverse cycle air conditioner | 10-14c |
| Electric panel heater | 46-62c |
| Electric portable heater | 92c-$1.25 |
If you are choosing between appliances to keep warm this winter, our cheapest way to heat a home guide compares every option.
How to cut air conditioning costs
Set a sensible temperature
The SA Government suggests 24°C to 27°C for cooling and 18°C to 21°C for heating. Each degree closer to the outside temperature saves 5% to 10%.
Only cool the rooms you use
Close internal doors and use zone controls on a ducted system. Cooling a closed living room costs far less than the whole house.
Block the sun first
Close blinds and curtains on north and west windows before the day heats up. It is cheaper to keep heat out than to remove it.
Clean the filters
Dusty filters make the unit work harder. Most indoor units have filters you can rinse every few weeks during heavy use.
Run it in cheaper hours
On a time-of-use plan, pre-cool the house before the 4pm peak, or use free midday power from the Solar Sharer Offer.
Check the zoned energy label
Non-ducted air conditioners sold in Australia carry a zoned energy rating label with separate ratings for hot, average and cold climates. Compare models on the rating for your zone, not just the star count.
Questions about air conditioner running costs
It depends on the size of the unit and your rate. On the NSW Ausgrid reference price, a small split system drawing about 750 W costs around 25c an hour, a medium 1.5 kW unit about 50c and a large ducted system drawing 4.3 kW about 142c.
Usually not. Running a unit while nobody is home uses energy for no benefit. The exception is a well-insulated home on a time-of-use plan, where cooling in cheap midday hours and coasting through the peak can cost less. Our guide on leaving the air con on covers this in detail.
Compared with an electric heater, almost always. A reverse cycle unit delivers three to six units of heat per unit of electricity, while a fan, panel or oil heater delivers one. The SA Government estimates a small reverse cycle unit costs 10c to 14c an hour to heat a small room, against 46c or more for a panel heater.
A ducted system drawing 4.3 kW for five hours a day, all year, would cost about $2,600 on the Ausgrid reference price. Most homes run ducted systems for part of the year and with only some zones open, so real costs are usually lower.
The SA Government suggests 24°C to 27°C for cooling and 18°C to 21°C for heating. Each degree further from the outside temperature adds about 5% to 10% to energy use, according to energy.gov.au.
Sources
Every rate on this page comes from the regulator or the regulated retailer. Last checked October 2026. Prices include GST unless we say otherwise.