How Much Does a Split System Air Conditioner Cost to Run? (Australia 2024)

One of the most common questions we get is: how much will my electricity bill increase if I install a split system? The answer depends on the unit's efficiency, usage patterns and your electricity tariff. Here's a detailed breakdown to help you budget accurately.

How Air Conditioner Running Costs Are Calculated

Running cost = capacity (kW) ÷ COP (Coefficient of Performance) × hours used × electricity rate ($/kWh)

The COP tells you how much heating or cooling you get per kW of electricity consumed. A modern inverter split system typically has a COP of 3.5–5.5, meaning it produces 3.5–5.5kW of cooling for every 1kW of electricity used. This is why air conditioners are far more efficient than electric heaters.

Sample Running Costs by Unit Size

Assumptions: Australian average electricity rate of 32c/kWh, running 8 hours per day, modern inverter split system.

• 2.5kW unit: Approx. $0.59/hour, or $4.70/day, $47/month if used daily
• 3.5kW unit: Approx. $0.80/hour, or $6.40/day, $64/month if used daily
• 5.0kW unit: Approx. $1.09/hour, or $8.75/day, $87.50/month if used daily
• 7.0kW unit: Approx. $1.52/hour, or $12.14/day, $121/month if used daily

These are worst-case estimates (maximum cooling). In practice, an inverter air conditioner runs at reduced power once the room reaches your set temperature, so actual costs are typically 30–50% lower than these figures.

Tips to Reduce Running Costs

• Set to 24–26°C for cooling: Every degree cooler increases running cost by approximately 10%. 24°C is comfortable; 20°C wastes money.
• Use the timer: Set the AC to turn off after you're asleep (most people sleep fine at 26°C).
• Keep doors and windows closed: Every air gap lets cool air out and hot air in.
• Use ceiling fans together: A fan circulates cool air effectively and allows you to set the AC 2°C warmer, saving around 20% on running costs.
• Service the unit annually: Dirty filters and coils reduce efficiency by 10–20%.

Heating in Winter

Reverse-cycle split systems are also the most efficient way to heat your home. At Sydney temperatures, the heating COP is typically 4–6 — meaning you get 4–6kW of heat for every 1kW of electricity. Far cheaper than gas or electric bar heaters.

Compare Before You Buy

When choosing a split system, compare the star rating and energy label data. The label shows estimated annual energy use in kWh, allowing direct cost comparison. A 5-star unit vs a 3-star unit of the same capacity can save $50–$150 per year.

Get a Split System Installed in Sydney

Oceania Appliances stocks and installs Mitsubishi Electric, Daikin, Panasonic and Fujitsu split systems. Supply and install from $499. Call 0481 243 211 or visit 2/14 Centre Place, Wetherill Park. Open 7 days, 10am–8pm.