How much that airconditioner is really costing you

Standby power: our worst home appliances

Even when turned off, standby power means these devices continue to guzzle alarming amounts of electricity.

Australian families could save more than $700 on their energy bills by reducing their airconditioning habits this summer, a national survey reveals. 

Two-thirds of Australians who have airconditioning are guilty of bad habits  such as leaving it on when they leave the house or to cool the kitchen while using the oven, the energy plan comparison site Mozo found. Mozo estimates the collective cost of airconditioning habits of Australians to hit $2.5 billion this summer alone. 

A substantial portion of that is while we are sleeping. Nearly three in 10 people leave the airconditioner on overnight so they can sleep under a doona, said Mozo's director Kirsty Lamont.

Comfortable in the cool but at what cost?
Comfortable in the cool but at what cost?  Photo: SolStock

"This is Australia's most expensive bad habit, with an eight-hour a night aircon habit adding around $270 to your bill over the summer, or $1.1 billion nationwide," Ms Lamont said.  

"And while leaving the aircon on for a dog or cat might be necessary during a heat wave, over a quarter of people are leaving the air on for a pet while they go out when there might be a cool shady spot outside or a fan that can keep them comfortable inside." 

The survey found that 7 per cent of people were guilty of leaving aircon on to dry laundry in summer, contributing more than $57 million to the national energy bill. 

"In one sense, it's not a bad idea because airconditioning reduces moisture in the air, but really, if it's a sunny Sydney day it would be more efficient to dry your clothes outside," said Chris Martell, director of Global Sustainable Energy Solutions. 

"The worst guilty habit is people aren't monitoring a leaky house - cool air sinks and it will slide through cracked windows and from under doors, so sealing those cracks in multiple rooms is essential."

The findings highlight ways to cut down aircon use and save on bills. 

Tips to save money on summer airconditioning: 

  • Each degree warmer will save you 10 per cent off your energy bill, so when the AC is on, aim for a comfortable 24 degrees rather than aiming for Arctic. 
  • Open windows at night to allow cool breeze in, kick off the covers and sleep under a thin sheet. 
  • If you do have the aircon on, close windows and doors and use a door snake to keep the cold air in and turn it off once the room is cool. 
  • Instead of leaving the aircon on while you go out on a hot and sunny day, close up the house and draw the blinds. 
  • Install a cat or dog door so your furry critters can let themselves in and out and find the coolest place around, unless there's a heat wave.  
  • Make the most of summer evenings by cooking on the barbecue or enjoying salads and quick pastas rather than switching the oven on. 
  • Check the forecast and do your washing on a sunny day so you don't need to hang the laundry in front of the AC unit or use the dryer. 
  • Invest in door draft stoppers.