Aircon Running Cost Calculator: Get Your Cost & the Right System for Your Home
Not sure which air con suits your home? Answer a few quick questions — honest advice from your local Mandurah team.
What do you want to cool?
How we pick your best fit
The recommendation comes from two things you tell us: how much of your home you want to cool, and whether you need heating as well. That's it — the pick is about suitability for your home, not about which system is cheapest to run. Running cost is the number we show you afterwards so you can compare, but it never decides the recommendation.
If you need heating (or aren't sure), cooling-only systems — like Ducted Evaporative — are filtered out of the top spot, because they simply can't heat.
| Area to cool | Heating? | Best fit | Also consider |
|---|---|---|---|
| Single room | Yes / not sure | Split System | Ceiling Cassette |
| Single room | Cooling only | Split System | Ceiling Cassette |
| A few rooms | Yes / not sure | Multi Head | Ceiling Cassette, Ducted Reverse Cycle |
| A few rooms | Cooling only | Multi Head | Ceiling Cassette |
| Whole home | Yes / not sure | Ducted Reverse Cycle | — |
| Whole home | Cooling only | Ducted Reverse Cycle | Ducted Evaporative |
The six systems we install
- Split System — one indoor unit for a single room or zone; reverse cycle (cools and heats); the most efficient per-room option.
- Multi Head — one outdoor unit serving several indoor heads; good for a few separate rooms; reverse cycle.
- Ceiling Cassette — ceiling-mounted, ideal for open-plan areas or rooms with no free wall space; reverse cycle.
- Ducted Reverse Cycle — whole-home cooling and heating from one ducted system; refrigerated, and works well in humidity.
- Ducted Evaporative — whole-home cooling only; very low running cost; suits dry heat like Mandurah summers; needs windows or doors cracked for airflow, and is less effective in humidity.
How we work out running cost
Refrigerant systems (Split, Multi Head, Ceiling Cassette, Ducted Reverse Cycle): the quoted capacity is the cooling or heating output in kW, not the electricity the unit draws. We divide the capacity by the unit's efficiency — EER for cooling, COP for heating — then apply a 0.7 load factor to allow for real-world cycling (the compressor doesn't run flat-out the whole time).
input power (kW) = capacity ÷ efficiency × 0.7
cost per hour = input power × tariff
Worked example: a 5.0 kW split system cooling with an EER of 4.0 draws about 5.0 ÷ 4.0 × 0.7 = 0.875 kW. At 33.26 c/kWh that's roughly $0.29 an hour, or about $2.33 a day at 8 hours' use.
Ducted Evaporative works completely differently — it's just a fan and a water pump, with no compressor. We use a fixed electrical draw of 1.2 kW, which is why it's so much cheaper to run. The trade-off: it's cooling only, works best in dry heat, and needs a bit of airflow through the house.
Daily, weekly and seasonal costs simply multiply the hourly cost by your hours per day and season length.
A note on the numbers
Estimate only — a guide for comparing system types, not a quote. Figures use the Synergy Home Plan A1 usage rate (33.26 c/kWh from 1 July 2026) and exclude daily supply charges. Real running costs depend on the weather, your home's size and insulation, thermostat settings, and the specific model's efficiency. For advice tailored to your home, speak with the iBreeze team.
Get the right system, sized right, from locals
Free, no-obligation quote with honest right-sizing advice — no pushy sales talk, just straightforward help from a Mandurah team with 150+ five-star reviews.
- Honest right-sizing advice so you get the system your home actually needs — never oversold
- No-obligation quote with everything itemised upfront — no surprises
- Quality brands installed by licensed technicians, supervised by the iBreeze team
- Local knowledge of Mandurah's climate — we'll tell you straight if evaporative suits your street
- After-sales support from a team that's a phone call away, not a call centre