Metered Baseline Method
(including NABERS)
Related Documents
The Metered Baseline Method uses the measurement of electricity consumption “before” the RESA takes place, to establish a “baseline” electricity consumption standard for the Site being considered. The same measurement is performed “after” the RESA has commenced and will establish new levels of electricity consumption, with the difference representing the impact of the RESA.
The Metered Baseline Method relies on the remainder of the Site operating as it did before the RESA was implemented.
A number of different sub-methods are provided in the ESS Rule for the determination of the baselines and the calculation of ESCs using the Metered Baseline Method, as below:
- using a baseline per unit of output;
- using a baseline unaffected by output;
- using a normalised baseline; or
- using the National Australian Built Environment Rating System (NABERS) baseline.
Each of the listed sub-methods is described briefly below. For more detailed information please refer to the ESS Rule and the ESS Application Guide.
Baseline per unit of output
This method is most appropriate where consumption is strongly linked to output (eg, aluminium smelting).
You may use this method if:
- The consumption of all energy sources for the Site are linear functions of output (that is they directly reflect each other).
- Where the energy consumption is fixed (that is, the proportion of energy consumed at the Site does not vary with variations in output) can be measured or estimated.
- Output has not changed by more than 50% from the average output over the period that the variable baseline was measure.
Baseline unaffected by output
This method is most appropriate where consumption is not linked to output (eg, schools and swimming pools).
Normalised Baseline
This method is most appropriate where the baseline needs to be normalised to remove explainable variation from the baseline. Examples may include changes to ambient conditions or input characteristics.
NABERS Baseline
The National Australian Built Environment Rating System (NABERS) method is based on the Normalised Baseline approach and consists of two methods, Method 4a and Method 4b in the Rule. Method 4a is for Existing NABERS Buildings and Method 4b for New NABERS Buildings. These methods are to be used for normalising baselines of offices, hotels and shopping centre buildings which use the NABERS for measuring building energy performance.
