When determining a reported baseline number, the Clean Energy Regulator must adjust scope 1 covered emissions for the period 2009-10 to 2013-14 to reflect the current global warming potential (GWP) values as specified in the National Greenhouse and Energy Reporting Regulations 2008 (NGER Regulations) at the time the reported baseline determination is made (section 17 (6) of the Safeguard Rule).
For the 2015-16 reporting year, the NGER Regulations have been amended to incorporate updated values for GWPs of greenhouse gases based on the findings of the Intergovernmental Panel on Climate Change’s Fourth Assessment Report. As the GWP of some greenhouse gases has changed, the Clean Energy Regulator must make GWP adjustments to scope 1 covered emissions for the purposes of determining a reported baseline number.
These include:
-
carbon dioxide
-
methane
-
nitrous oxide, and
-
perfluorocarbons attributable to aluminium production.
The changes in GWP and adjustments to scope 1 covered emissions are detailed in the table below.
Changes in GWP and ratio applied to adjust scope 1 covered emissions
|
Greenhouse gas |
GWP pre 2015-16 |
GWP 2015-16 onwards |
Conversion ratio |
|---|
| Carbon dioxide | 1 | 1 | 1.0 |
| Methane | 21 | 25 | 1.190476190476 |
| Nitrous oxide | 310 | 298 | 0.961290322581 |
| Perfluoromethane (tetrafluoromethane) | 6,500 | 7,390 | 1.136923076923 |
| Perfluoroethane (hexafluoroethane) | 9,200 | 12,200 | 1.326086956522 |
| Sulphur hexafluoride* | 23,900 | 22,800 | 1.0* |
| Hydrofluorocarbons(HFCs)* | dependent on HFC type | dependent on HFC type | 1.0* |
*While the GWP of sulphur hexafluoride and some HFCs have changed from 2015-16 onwards, the Clean Energy Regulator will not make GWP adjustments to these greenhouse gases unless requested by the responsible emitter, with sufficient supporting information. Therefore, the ratio for these greenhouse gases is 1.0.