ZERL - Understanding The New Energy Rating Labels

When you’re buying a new air conditioner, the upfront price is only part of the story. The real cost comes from how much energy it uses over time.

That’s why all AC units sold in Australia must meet Minimum Energy Performance Standards (MEPS) and display an official Energy Rating Label - so you can compare energy efficiency before you buy.

From Stars to Zones — What has Changed?

For more than 30 years, Aussies have relied on the Energy Star Rating Label — the colourful sticker with stars you’ve seen on appliances.

The old energy labels had one big flaw - they only tested efficiency at a single outdoor temperature. That meant you got just one “average” result for Australia - from Hobart to Perth, and even Darwin - even though your AC systems perform very differently in each climate.

To fix that, the government has introduced the new Zoned Energy Rating Label (ZERL) - a major upgrade that makes energy ratings more accurate based on where you live.

The Old Energy Star Rating System

What You Found on The Old Energy Star Rating Label:

1. AC Brand and Model

   This showed the brand and model of the AC unit, so you could check you were looking at the right information for the right AC unit.

2. Star Rating

   This showed how energy-efficient the unit was compared to others of similar size. More stars = better efficiency.

3. Capacity Output & Power Input (kW)

   This showed the amount of electricity the unit used when running at full output (Power Input kW), and the amount of heating or cooling it delivered (Capacity Output kW).

While this was helpful for that time, it did provide a distorted result for air conditioning usage. Many consumers bought AC systems based on the high star rating but didn't see the energy-efficiency reflect in their electricity bills.

Introducing the New System: Zoned Energy Rating Labels (ZERL)

The ZERL system is a real game-changer. It gives you a clearer, more accurate view of how your air conditioner performs by factoring in Australia’s different climate zones and seasonal conditions.

What You’ll Find on a ZERL Label

1. AC Brand and Model

   This will show the brand and model of the AC unit, so you can check you are looking at the right information for the right model AC unit.

   
   

2. Climate Zones (Hot / Average / Cold)

   It covers three climate zones across Australia and New Zealand: You’ll see separate blue (cooling) and red (heating) star ratings for each zone. This lets you compare how the unit performs in your specific region.

   • Hot Zone: Brisbane, Darwin, Pacific Islands

   • Average Zone: Sydney, Perth, Adelaide

   • Cold Zone: Melbourne, Hobart, Canberra, New Zealand

     
     

3. Zone Star Ratings (Energy efficiency)

   This tells you how efficient the AC unit is in the form of star ratings (0-10 stars). The more stars, the less energy consumption.

   • Blue stars: How efficient the unit is at cooling.

   • Red stars: How efficient the unit is at heating.

     
     

   👉 Tip: Find your climate zone on the map shown on the label and check those stars only. A model might rate 8 stars in a hot zone but only 5 in a cold one.

   
   

4. Zoned Energy Consumption (kWh per year)

   This is the best part! The ZERL gives separate annual energy use figures (in kWh per year) - one for each climate zone - for both heating and cooling. The Energy Use figures are a general consumption guideline only. Actual energy usage may vary depending on how often you use your air conditioning system and the temperature settings when you use your AC.

   
   

   We have listed a few points on how to run your AC efficiently in our post Essential Guide to Choosing and Energy-Efficient Air Conditioning Unit

   
   

   👉 Tip: To calculate estimate annual running costs for your area, multiply the figure given for your climate zone by your electricity tariff found on your electricity bill.

   
   
   
   

5. Capacity Output Heating (kW)

   This shows how much heating power the AC system can deliver at different outdoor temperatures. This example compares two sets of outside cooling temperatures:

   
   

   i) If the outside temperature is a cold 7°C, the unit can provide 5.5kW of heating.

   ii) If the outside temperature is a near freezing 2°C, the unit can provide 8.8kW of heating.

   
   

6. Capacity Output Cooling (kW)

   This shows how much cooling power the AC system can deliver. This example shows you that the AC unit can provide 4kW of cooling when the outside temperature is a hot 35°C.

   
   

   💡 Why Capacity Matters: This helps you see how well the unit performs during temperature extremes — so you can choose a system that keeps up during heatwaves or freezing snaps.

   
   

7. Noise Levels (dB(A))

   This tells you how loud the AC unit will be if it is running at maximum capacity at full cooling power. 

   
   

   Depending on the brand and type of AC unit there may be an indoor or outdoor noise rating. The ratings display noise levels in decibels.

   
   

   For comparison, here are some common sound levels (in decibels): 

   • 30dBA (soft): a typical whisper

   • 50dBA (moderate): the hum of a refrigerator

   • 60dBA (moderate): having a normal conversation

   • 75dBA (loud): an operating vacuum cleaner

   
   

   💡 Why it Matters: Lower numbers mean a quieter operation. External noise levels may be important if the outdoor units are placed near a window or close to a boundary line. Some body corporates may also have specific requirements regarding noise levels produced by air conditioning units while in operation.

Why am I Seeing Both Energy Ratings Labels in Stores!?

If you’ve noticed some air conditioners with the old Energy Star Rating label and others with the new ZERL label, don’t worry - that’s completely normal. This is because an overlap of when the ZERL was introduced.

If you are planning on purchasing an air conditioning system that has both the old start rating label and the new ZERL rating label we urge you to focus on the ZERL rating and not compare them against each other.

Why Can I Not See the ZERL on Units Online?

At the moment, Zoned Energy Rating Labels (ZERLs) are only displayed on physical units in-store, so you won’t find them on most online product listings. 

But if you’re shopping online, don’t worry - you can still access full ZERL ratings and energy performance data digitally through the Government's Energy Rating Calculator for Consumers.

Need help? Check out our Simple Guide to Using the ZERL Energy Calculator on the National AC Parts blog to learn exactly how to use it and compare ZERL information with ease. 

Conclusion

Australia’s climate is anything but one-size-fits-all, and the new ZERL system finally reflects that. It gives you a clearer, more accurate picture of how efficiently an air conditioner will perform in your local conditions - whether you live in the tropics or the snow.

Ready to Upgrade? 

Our team at National AC Parts can help you find the right energy-efficient unit for you. Call us on 1300 904 554 or email info@nationalacparts.com.au.