11 Feb 2005, 02:37:37 PM


As we progress, everybody wants to have the new things that make our lives more comfortable. But perhaps we are getting a bit soft.

No matter what the temperature outside, chances are you're watching this from the comfort of your artificially cooled lounge-room.

"They certainly were a luxury at some point. For some people they would still be a luxury, but they're becoming much more a standard feature in homes," Shelley says.

They sure are... up to one hundred thousand air conditioning systems have gone into West Australian homes in the past year.

Shelley Liddelow from the Office of Sustainable Energy...

"Air conditioners have come down in price quite a lot in recent years, they're not cheap to buy but they have come down in price."

So what should you keep in mind when you're choosing a system for your home?

"In Australia, we're one of the world's worst polluters, per capita."

Tom Carlton is a consultant on a programme encouraging shoppers to "reach for the stars" - the energy efficient ones.

"Whilst they may not pollute hugely, one air conditioner, if everyone in Australia's got one, then it's a big consideration," says Tom.

The basic choices for the home are evaporative or refrigerative.

"Some people prefer evaporative coolers because you get an air flow through the house with outside air coming in, you need to have a door or window open. With refrigerative you need to have your doors and windows closed but they're very good when it's a bit humid." says Shelley.

The cost of the unit is one thing, but running it can also be pricey.

The average split system refrigerative unit will cost you between eighty cents and a dollar to run, per hour to cool the whole house - that works out at about three hundred dollars a year.

Compare that with an evaporative system. It'll cost around four cents an hour to do one room, or between ten and fifteen cents an hour to do the whole house.

An inverter model is new technology appearing on the shelves. Where reverse cycle stops and starts to maintain a temperature, an inverter cruises.

"It's like driving a car - stop start driving uses much more fuel than if you're just cruising so it's worthwhile buying an inverter - even if they do cost more when you buy them, you'll save money with the energy," says Tom.

And the more stars on your unit, the less you'll pay to run it.

"If you selected a four star model instead of a two, you would probably reduce your running costs by about 25 per cent and by a third selecting a four star model against a one-star model," says Shelley.

Tom Carlton says we also shouldn't discount the humble ceiling fan.

"A ceiling fan will cost about 2 cents an hour so it'll cost you 12 dollars a year to run - I mean it's almost nothing."

The other consideration... what's best for your size house?


Small Home

Tom reckons an evaporative system is adequate for a small home - assuming you get an evening breeze.

Medium Home

For the average three bedroom home, he suggests refrigerative - a ducted system to do the whole house, or if you prefer to shut unused sections off, a reverse cycle in the living area and smaller ones in the bedrooms.

And a large house?

"Absolutely got to go ducted."

But these suggestions before you put in any air conditioning.


1. Reduce the heat

For example, if you're in a position to draw your blinds and your curtains -that will help because most of the heat enters your home through your windows and through uninsulated ceilings.

2. Make sure your home has ceiling insulation - don't put in any air conditioning till you've got it.

It'll cost you perhaps 30 per cent more to run your air conditioner if you don't have ceiling insulation.

3. Make sure your air conditioners the right size for the area you want to cool.

4. Close off the rooms you're not using.

5. Set a comfortable temperature - around 25 degrees.

“For every degree lower that you set your air conditioner, down to about 21degrees, you're paying up to 10 per cent more, so you can save 30- 40 per cent of your running cost by setting it at 25 degrees - and for most people who're wearing appropriate summer clothing, that's fairly comfortable," Shelley says.