Electricity emissions under Australia's mandatory sustainability reporting standards
The Australian Sustainability Reporting Standards (ASRS) are mandatory climate-related financial disclosure requirements issued by the Australian Accounting Standards Board (AASB). Based on the ISSB's IFRS S1 and S2 standards, ASRS became mandatory from financial years starting on or after 1 January 2025 for large reporting entities (Group 1), with phased rollout to smaller entities through to FY2028.
Under ASRS, affected companies must disclose their greenhouse gas emissions across Scope 1 (direct), Scope 2 (purchased electricity and energy), and Scope 3 (value chain). For most commercial and industrial organisations, purchased electricity is the single largest contributor to Scope 2 emissions and often the most material disclosure item.
ASRS requires entities to disclose the methodologies used for emissions calculations and to provide sufficient detail for users of the financial statements to understand the basis of reported figures. This places increased scrutiny on the quality and granularity of Scope 2 calculations.
Scope 2 emissions are indirect greenhouse gas emissions from the generation of purchased electricity consumed by the reporting organisation. They are measured in tonnes of CO₂ equivalent (tCO₂e) and calculated by multiplying electricity consumption by an emission factor that represents the carbon intensity of the grid.
The GHG Protocol — the international standard referenced by ASRS — defines two methods for Scope 2 calculation. Reporting entities should understand both, as they can produce materially different results depending on when and where electricity is consumed.
Uses a single annual average emission factor published by DCCEEW (Department of Climate Change, Energy, the Environment and Water) for each state or territory grid region. This is the simpler approach — multiply total annual consumption by the regional factor. However, it treats all kilowatt-hours as equal regardless of when they were consumed, masking the real emissions profile of organisations that operate during high-renewable or high-coal periods.
Matches each consumption interval (typically 30 minutes) to the actual grid carbon intensity at that point in time. This produces 17,520 individual calculations per year, each reflecting the real generation mix when electricity was consumed. The market-based approach rewards organisations that shift load to low-carbon periods and accurately reflects the emissions impact of operational decisions like running manufacturing during midday solar peaks versus overnight coal-heavy baseload.
The difference between methods can be substantial. A daytime manufacturer in NSW consuming primarily during high-solar periods may see time-matched emissions 20–30% below the location-based figure. An overnight operation in Victoria running on brown coal baseload could see time-matched emissions 15–20% above. For an entity consuming 10,000 MWh per year, this represents hundreds of tonnes of CO₂e — material for any sustainability report.
Annual average emission factors obscure the most important information for emissions management: the relationship between when you consume and what the grid looks like at that moment. Time-matched Scope 2 provides this granularity.
Under ASRS, robust methodology disclosure is expected. Auditors and investors increasingly scrutinise whether reported figures reflect actual operating conditions. Time-matched calculations demonstrate a level of rigour that annual averages cannot — and they align with the direction of international best practice, including the GHG Protocol's guidance on market-based instruments and temporal matching.
Time-matched data also creates a direct link between operational decisions and reported emissions. This enables organisations to quantify the emissions benefit of load shifting, on-site solar, battery storage, and renewable PPAs in terms that are directly reflected in their ASRS disclosures. Read our detailed explainer on time-matched Scope 2 for worked examples.
The Department of Climate Change, Energy, the Environment and Water publishes annual Scope 2 emission factors for each state grid. These are used for location-based calculations:
Note that these factors are published with a lag — typically reflecting the generation mix of the previous financial year. They do not capture intra-year changes in the generation fleet, such as new renewable capacity coming online or coal station closures. Time-matched calculations using live grid data are inherently more current.
gridIQ provides the data infrastructure for robust Scope 2 reporting under ASRS:
Every gridIQ account includes a 14-day Professional trial with full access to dual-method Scope 2 tracking. After the trial, carbon intensity data and Scope 2 calculations are available on Team ($349/month) and Professional ($749/month) plans. Create your account to start tracking your electricity emissions under ASRS today, or explore our pricing plans to find the right tier for your organisation.