The biggest energy wasters in Australian air conditioning
5 December, 2025
Key Takeaway
Most of the energy wasted in Australian homes comes from cooling or heating rooms no one is using, using inaccurate temperature readings and forcing the system to push the same airflow everywhere. Fixing these issues can cut energy use without reducing comfort.
1. Cooling or heating rooms that are empty
This is by far the number one energy waster.
Most standard systems run large zones that include bedrooms, hallways or studies even when no one is in them. It feels normal because that is how air conditioners have always worked, but it is incredibly inefficient.
Why it wastes energy:
The system spreads its cooling or heating power across too many rooms, so it runs longer and uses more electricity to get the same result.
How to fix it:
Control rooms individually. Cool only the spaces in use. This single change cuts energy use instantly.
2. Relying on a hallway thermostat
A hallway is one of the worst places to measure temperature. It isn't lived in, heats slowly, cools quickly and does not reflect real comfort conditions.
Why it wastes energy:
The system overruns. It keeps cooling because the hallway is still warm, even though your living room or bedroom is already cold. The opposite happens in winter.
How to fix it:
Use room based temperature readings so the system stops when the room is actually comfortable.
3. Airflow that is the same in every room
Different rooms need different amounts of airflow. A west facing room needs more cooling. A shaded bedroom needs less. Many systems push the same airflow everywhere because it is simpler.
Why it wastes energy:
Some rooms never reach comfort, so the system keeps running. Other rooms over cool and waste power.
How to fix it:
Fine tune airflow room by room instead of treating the home as one space.
4. Setting extreme temperatures
Turning the system down to 16 degrees does not cool the home faster. It only makes the system run longer.
Why it wastes energy:
Every degree lower in summer or higher in winter increases energy use significantly.
How to fix it:
Use moderate settings such as 24 to 25 degrees in summer and 18 to 20 degrees in winter.
5. Running the system longer than needed
A system left on while the home is empty burns energy for no benefit.
Why it wastes energy:
Air cons use the most energy maintaining temperature, not reaching it.
How to fix it:
Use simple schedules and remote access so the system only runs when needed.
6. Poorly timed cooling or heating
Homes heat and cool predictably. West facing rooms warm in the afternoon. Bedrooms cool quickly at night. Many people run the system reactively instead of preparing the home beforehand.
Why it wastes energy:
Cooling after a room gets hot takes more energy than preventing the heat from building in the first place.
How to fix it:
Pre cool or pre warm the specific rooms that need it before the heat or cold peaks.
7. Closing vents manually
A lot of people try to save energy by shutting vents, but this usually backfires.
Why it wastes energy:
Closing vents creates pressure in the ductwork which makes the system work harder and use more power.
How to fix it:
Adjust airflow gently rather than shutting vents completely.
The truth about energy waste
Energy waste is not caused by the air con unit itself. It is caused by the way the home is controlled. The more precisely a system can see each room and adjust accordingly, the less energy it wastes. That is why features like zoning, room based sensors and automation have become essential for households wanting both comfort and lower running costs.
Learn how MyPlaceIQ can save you up to 46% on air-con running costs. MyPlaceIQ is a super smart air-conditioning system that integrates with a range of smart home products that increase your comfort, control and most importantly increase your energy efficiency.
