Giving a definitive answer to how much an air conditioner will cost to run in YOUR home is too subjective. Amongst other things it will depend upon:
The difference in temperature between inside and outside your home
How much you pay in electricity per kW hour
How many windows you have (and whether you keep them closed)
Airflow dynamics within your home
Level of insulation
What time of the day you turn the air conditioner on
Whether you live in Ipswich or surrounding country areas
What your comfortable living temperature is
You can however compare between different types of air conditioners and different models
SPLIT SYSTEMS VS DUCTED
If you had a split system in EVERY ROOM of your home and ran them all they would have a higher running cost than a whole home ducted system. HOWEVER, most people only have a single split in the lounge and one in the main bedroom, in this case it would be cheaper to run only the split system in the bedroom over night than the ducted for a portion of the house.
On the flip side of that if you have a couple of bedrooms being cooled or heated overnight the new SMART control systems allow the ducted to ramp down and are becoming more and more economical as a comparison to only a couple of split systems
Another consideration is standby running costs. This is the power consumed by the system whilst it is waiting to be turned on via the remote. Consider that the average standby consumption of a split system is 30-50 watts per hour. a single split system air conditioner can consume 260kwh per year (or more) JUST ON STANDBY. At 23c/kwh this can work out to be about $60 per year just to have the air conditioner ready to be turned on; PER SPLIT SYSTEM.
By comparison, a ducted system may consume a little bit more, ie 40-80 w/h but that is certainly less than having 4-6 split system air conditioners.
Also, annual maintenance on a ducted system will also cost significantly less than multiple split systems.
BETWEEN DIFFERENT BRANDS OF THE SAME SIZE AIR CONDITIONER
It is possible to compare the running costs of the brands by assigning the following equation to each one’s specifications to put it into a monetary value to make comparison easier
This is worst-case dollar figure consumption if the system worked at 100% capacity, 100% of the time. However, the systems are not designed to work like this and the inverter technology is supposed to allow the system to reduce its consumption as it approaches the set-point temperature. so this absolute consumption cost figure should only be used to compare efficiency between similar capacity systems and not as a guide to actual running costs.
SMART CONTROL SYSTEM EFFICIENCY
There are many benefits to having a SMART controller for your ducted air conditioner and one of the main ones is the increase in efficiency for the system. A SMART controller with individual zone temperature sensors will cool/heat more effectively than a standard zoned controller because as each zone reaches its set-point temperature, that zone will close, and the air will be directed into the other areas that haven't yet reached their set-points. This reduces the time it takes to cool the areas, which reduces the amount of power that the system will use.
From this point, the controller will modulate the opening and closing of the zones to send air only where it is needed, when it is needed, keeping you more comfortable for less money.
To make sure you know what energy your air conditioner and other appliances are actually using, iZone have an affordable energy monitoring system that you can connect to your smart device to watch what devices consume power during the day. Each device can monitor up to 3 circuits and up to 5 devices. AND you don't need the iZone air conditioning controller to operate the energy monitors.