Scope 3 electricity emissions are the upstream emissions linked to the electricity an organisation uses, beyond the generation counted in Scope 2. The NGA Factors publish a Scope 3 factor for each state and grid next to the Scope 2 factor, so both can be estimated from the same consumption data.
Key points
- NGA publishes Scope 2 and Scope 3 electricity factors by state and grid
- Scope 3 factors include electricity lost through the grid network
- Location-based and market-based factors each have Scope 2 and Scope 3 values
- Scope 3 is not reportable under NGER but is required by AASB S2
What the Scope 3 factor includes
DCCEEW states that the Scope 3 electricity factors include electricity lost through the grid network in their derivation. The workbook also publishes transmission and distribution loss data. Scope 2 factors are defined in terms of energy sent out to the grid rather than energy delivered.
How the calculation works
- Take electricity consumed in kilowatt hours for each site, by state or grid.
- Multiply by the Scope 2 factor for that state or grid to estimate Scope 2.
- Multiply the same quantity by the Scope 3 factor for that state or grid to estimate the related Scope 3.
- Use the edition that matches the period being estimated and record it.
Location-based and market-based
The workbook provides location-based factors by state and grid, and a national residual mix factor for the market-based method, each with a Scope 2 and Scope 3 value. Under NGER, the Measurement Determination notes that market-based results should not be aggregated with location-based results, and the same discipline keeps voluntary inventories clear.
Where the estimate is used
The Clean Energy Regulator states that Scope 3 is not reportable under the NGER Act 2007 but that the NGA Factors can be used to estimate it. AASB S2 requires Scope 3 disclosure, with transitional relief in the first annual reporting period, so these estimates typically feed sustainability reports and voluntary inventories.
Why it matters
For energy-intensive sites, Scope 3 from electricity is small next to Scope 2 but is one of the easiest Scope 3 categories to calculate accurately, because it uses the metered consumption already collected for NGER. Reusing the same data, with the NGA factor edition recorded, keeps the Scope 2 and Scope 3 figures consistent.
References & sources
Primary regulatory documents and authoritative references underpinning this answer.