What affects how much it costs to run an air conditioner?

Air conditioner running costs depend on your electricity plan, how many hours the unit runs, the temperature you set, its efficiency, whether it is the right size, and how well your home keeps heat out. There is no single figure, so look at these factors and ask a licensed professional about your home.

What makes up the running cost?

An air conditioner uses electricity, so the cost is the power it draws multiplied by the hours it runs and the rate your electricity plan charges. Each part of that equation can vary a lot between homes.

• Your electricity plan. Rates differ between retailers and between times of day, so the same unit can cost different amounts on different plans. Comparison sites say the plan is one of the biggest factors.
• Hours of use. Running a unit for most of the day costs far more than running it for a couple of hours.
• The temperature you set. The further you ask the unit to move the room from the outside temperature, the harder it works.
• Efficiency. The energy rating label shows how well a model turns electricity into cooling or heating.
• Size. An oversized or undersized unit can use more energy than a well-matched one.

How does my home change it?

Insulation, shading, curtains, window quality, and gaps around doors all affect how much heat leaks in or out. A well-sealed home with shade on the sunny windows needs less work from the unit. A hot west-facing room with no shade needs more.

Are inverter units cheaper to run?

Inverter units (those that adjust their speed rather than switching fully on and off) are generally more efficient than older fixed-speed units, which switch the compressor on and off at full power. Nearly all new split systems sold in Australia today are inverter types, though some older or portable models are not.

How do I see what my unit uses?

The model’s energy rating label and specifications show its rated power and efficiency. Your electricity bill and the Energy Made Easy comparison service can help you understand your plan’s rates. Keep a note of how many hours you run the unit to understand your own pattern. Our guide on lights dimming when the air conditioner starts covers one related electrical issue.

Does regular servicing affect cost?

A system that is looked after according to the manufacturer’s guidance is more likely to keep running efficiently. Choice also suggests professional servicing every few years as part of keeping a split system in good order.

Can solar help?

If you have solar, running the air conditioner during daylight hours can use power your panels make. How much this helps depends on your system and usage. A licensed professional can explain what suits your home.

Who can advise on my home?

A licensed professional can look at the unit, the size, the insulation and your usage and suggest what to change.