How Much Does It Actually Cost to Run Ducted Air Conditioning in WA?

It’s one of the most common questions our design consultants get asked, and for good reason. Ducted air conditioning is one of the biggest single investments you’ll make in your home’s comfort, and understandably, homeowners want to know what it’s actually going to cost to run before they commit. The honest answer is that it depends on a few different factors, but we can give you a genuinely useful idea of what to expect using current WA electricity pricing.

Current Synergy rates

As of 1 July 2026, most Perth households are on the Synergy Home Plan (A1), which charges a flat rate of 33.2621 cents per kilowatt hour, plus a daily supply charge of 119.2419 cents. Because the A1 tariff is a flat rate, it applies whether you’re running your aircon at 2pm or 10pm, which makes the maths a little more straightforward than it is in some other states.

If you’re on a time-of-use plan such as the Midday Saver, your rate will vary depending on when you run your system, and running your ducted aircon during the cheaper daytime window can make a noticeable difference, particularly if you’ve also got solar.

What actually determines running cost

Before we get to numbers, it’s worth understanding what drives them. Running cost comes down to:

• System size – a ducted system sized for a 4-bedroom home will draw more power than one sized for a 2-bedroom unit, simply because it’s moving more air and covering more area.
• Efficiency (star rating) – a higher star-rated system uses less electricity to produce the same amount of heating or cooling. This is genuinely one of the biggest levers on long-term running cost, not just the sticker price of the unit.
• Set temperature – every degree you push your thermostat further from the outside temperature increases how hard your system has to work. Setting your aircon to 22-24°C in summer rather than 18°C can meaningfully reduce your running cost.
• Zoning – conditioning only the rooms you’re using, rather than the whole home, reduces the load on your system significantly.
• Insulation and house design – a well-insulated, well-sealed home holds its temperature for longer, meaning your system doesn’t need to run as continuously.

Rough cost per hour

As a general guide, here’s what you can expect a typical ducted reverse cycle system to draw in electrical power, and what that translates to per hour at current Synergy A1 rates:

Note: Ranges reflect typical values; actual draw and running cost depend on efficiency rating, climate, and thermostat setting.

These figures are indicative rather than exact. Actual draw varies depending on the outside temperature, the set point, whether the compressor is running at full capacity or cycling, and how well zoned your system is. A well-zoned system running only two zones on a mild day will draw considerably less than these figures suggest.

Summer vs winter running costs

Reverse cycle systems generally work harder, and cost more to run, at the extremes of the temperature range. A 40°C day in Perth or a cold, single-digit morning in winter asks more of your system than a mild 28°C afternoon. Heating in particular can be misunderstood, as many people assume gas heating is always cheaper. In practice, a good quality reverse cycle system is often more cost-effective to run than ducted gas heating, particularly on the current A1 electricity rate, because reverse cycle systems generate multiple units of heat for every unit of electricity they consume, rather than converting energy one-to-one like a gas system does.

Putting it into context

A typical Perth household’s total electricity bill sits somewhere between $200 and $500 per billing cycle, depending on the size of the home and number of occupants. Ducted aircon is usually one of the largest contributors to that bill over summer and winter, but it’s rarely the runaway cost people expect once a system is correctly sized and zoned. Oversized systems, on the other hand, are one of the most common reasons homeowners end up with higher bills than they anticipated, which is exactly why correct sizing at the quoting stage matters so much.

Reducing your running cost without reducing comfort

• Set your thermostat a few degrees closer to the outside temperature rather than chasing extremes.
• Use zoning to condition only the rooms you’re in.
• Keep filters clean, as a dirty filter forces your system to work harder for the same result.
• Consider running your system during solar generation hours if you have panels installed.
• Have your system serviced regularly to keep it running at peak efficiency.

Get a figure specific to your home

General guides are useful, but every home is different, and the real answer to “what will this cost me to run” depends on your home’s size, insulation, orientation, and how you like to use your space. Our Design Consultants can talk you through expected running costs as part of an obligation-free quote, based on the specific system and zoning setup recommended for your home.

Get in touch with Ford & Doonan today to find out what a correctly sized ducted system would actually cost to run in your home.

Electricity pricing referenced is based on the Synergy Home Plan (A1) tariff, effective 1 July 2026, and is subject to change. Figures in this article are general estimates only and individual running costs will vary.