The National Australian Built Environment Rating System (NABERS) was developed by the NSW government in 1999. It subsequently expanded to a national framework. Now, it has announced significant changes to its rating program that will take effect from July 2030.
NABERS measures the operational performance of buildings across areas such as energy, water, waste, indoor environment quality and carbon neutrality.
At present, NABERS focuses on greenhouse gas emissions when calculating its rating. As such, NABERS Energy ratings uses emissions factors to convert the energy used by buildings – such as electricity, gas, LPG or diesel – into emissions as a comparable metric.
However, as Australia’s grid decarbonises, electricity emissions factors are declining rapidly.
This means the emissions intensity of electricity is expected to fall below the emissions intensity of gas in most parts of the country by 2030.
Eventually, buildings powered entirely by electricity will have very low annual emissions, regardless of how much energy they use.
If the program continues to rely solely on emissions factors, it could unintentionally reward buildings that achieve low emissions, but which are still consuming large quantities of electricity and hence not energy efficient.
This in turn could drive higher overall electricity demand from the built environment, place additional pressure on the electricity grid, and subsequently affect the relevance and intended impact of the NABERS star rating.
To support decarbonisation of the built environment, NABERS says that buildings need to achieve two outcomes simultaneously. The first is to reduce their energy intensity to reduce demand on the electricity grid and the second is to shift to low-emissions fuel sources such as renewable electricity.
It says that the proposed change encourages buildings to optimise for both outcomes simultaneously via the NABERS Energy Tool which includes the NABERS Star Rating that recognises and rewards low energy intensity with higher star ratings and the Renewable Energy Indicator which recognises buildings with low operational emissions through higher renewable energy percentages.
These measures, it adds, ensure that the NABERS Energy tool will continue to recognise and reward both low emissions as well as low energy intensity in buildings.
In most cases, buildings with higher NABERS star ratings are expected to have lower emissions than lower-rated buildings. The Renewable Energy indicator will clearly identify lower emission buildings.
The latest update will help ensure that the Energy ratings will compare all energy sources equally and will not reward buildings that achieve low emissions without also addressing energy efficiency.
The latest update has already been approved by the NABERS National Steering Committee and will apply across all building types and jurisdictions.
With around 83 percent of the country’s office spaces currently NABERS-rated, the latest announcement will impact a significant market segment. To help stakeholders align themselves with the upcoming changes, NABERS has published its updated prediction tools.
Image: Patrick Tomasso, Unsplash
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