Back

Cooling running costs

Family having a meal at the table in a large open-plan living area

The table below compares approximate annual running costs for various types of cooling systems for a range of room sizes.

Room size Cooler type Energy star rating Annual energy cost* Annual GHG emissions (kg/yr)
Room /Space cooling
Small room 12m2

Portable or ceiling fan N/A $2–3 10–15
Portable evaporative cooler N/A $5 20
Split system air conditioner
2 star rating $35 165
5 star rating $10 45
Medium room 30m2 Portable or ceiling fan N/A $5–10 25–35
Electric split system air conditioner 5.5kW output 2 star rating $50 235
5 star rating $20 95
Large area 60m2 2 portable or ceiling fans N/A $10–15 25–35
Split system air conditioner 8kW output 2 star rating $75 235
5 star rating $40 95
Central cooling
Small house 100m2 Ducted refrigerative air conditioning Not zoned 2 star rating $185 890
4.5 star rating $75 360
Zoned 2 star rating $175 835
4.5 star rating $70 320
Ducted evaporative cooling Standard $45 205
Inverter $35 170
Ceiling fans N/A $15–25 70–115
Medium house 160m2 Ducted refrigerative air conditioning Not zoned 2 star rating  $240  1,150
4.5 star rating $120 560
Zoned 2 star rating $225 1,065
4.5 star rating $105 495
Ducted evaporative cooling Standard $65 295
Inverter $50 235
Ceiling fans N/A $25–40 115–180
Large house 220m2 Ducted refrigerative air conditioning Not zoned 2 star rating $295 1,415
4.5 star rating $160 760
Zoned 2 star rating $270 1,300
4.5 star rating $140 670
Ducted evaporative cooling Standard $80 385
Inverter $65 305
Ceiling fans N/A $35–55 155–245

*Approximate energy cost per year, based on an average existing (pre 2005) 2-star house in a Melbourne climate, cooling all day on the weekend and in the morning and evenings when internal temperatures are high. Based on an electricity tariff of 27.5c/kWh. Note that the evaporative coolers will also use water and the cost of water is not included in this table. Actual costs for your house will depend on the area cooled, how long you run the cooling for, your thermostat settings, how well insulated and shaded the house us, your energy tariffs and your local climate.

To estimate running costs for a cold climate (for example, Ballarat) multiply these figures by 0.85, and for a warm climate (for example, Mildura) multiply these figures by 3.2. To estimate the running cost for a 5-Star house multiply these figures by 0.95, and for a 6-Star house multiply these figures by 0.85.

Use your cooling system efficiently

Remember, regardless of the type of air conditioner you have, if you operate and maintain your cooling system wisely you can reduce your cooling costs and still be comfortable.


A man and a woman shopping for electrical goods

Smarter choice

Energy efficient appliances will save you money. The Smarter Choice retail program will help you make better choices when buying new appliances, hardware and lighting.

Read more