On 29 September 2020, the AER released its decision on AusNet Services' 500kV transmission line tower collapse cost pass through application. AusNet Services’ application related to $25.8 million ($2020-21) in additional costs AusNet Services has incurred and will incur to restore transmission services and replace collapsed 500kV dual circuit transmission line towers on the Moorabool–Mortlake and Moorabool–Haunted Gully transmission lines in south western Victoria as a result of an extreme weather event that occurred on 31 January 2020.

The AER determined that AusNet Services’ application satisfied the definition of a natural disaster event in AusNet Services’ 2017–22 revenue determination and a positive change event under the National Electricity Rules. The AER approved a positive pass through amount of $2.3 million ($2020-21) to be recovered from network users in 2021-22.