Calculation of scope 1, scope 2 and scope 3; greenhouse gas (GHG) emissions are performed using activity data and GHG emissions quantification methodologies.
Activity data is a key input in to the calculation of GHG emissions. It refers to data associated with the activity that generated the GHG emissions. For example, activity data for emissions from purchased electricity may refer to electricity consumption amounts stated on supplier invoices. Activity data provides a measure for the level of intensity of the activity.
EPA reports its GHG emissions for each financial year period from 1 July to 30 June. Each year EPA collects activity data from around the organisation for all emission sources.
The purposes of the quantification methods are to calculate GHG emissions and express the quantity of emissions in a way that is consistent year-on-year and comparable with other organisations. EPA uses tonnes of carbon dioxide equivalent (t.CO2-e) as unit of measurement to quantify emissions. EPA’s GHG inventory includes all six greenhouse gases covered by the Kyoto Protocol – carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), and sulfur hexafluoride (SF6).
EPA relies on the quantification methods, including conversion factors, published by the Australian Federal Government and other reputable authorities. In circumstances where appropriate quantification methods are not available EPA uses assumptions. These assumptions are based on the best available information at the time the GHG inventory is prepared. Where assumptions are used, these are documented and made publicly available.
The following pages provide details of the activity data origins and quantification methods used to prepare EPA’s GHG inventory.
Scope 1 includes direct GHG emissions that occur from sources that are controlled by EPA.
Scope 2 includes indirect GHG emissions associated with purchased energy commodities including electricity and steam.
Scope 3 includes all other indirect GHG emissions that are a consequence of the activities of the organisation, but occur from sources not owned or controlled by EPA.