On Saturday the 7th of February 2009 bushfires devastated Victoria, Australia, killing 173 and injuring 414. Black Saturday, as it has become known, combined extreme temperatures (46.4°C in Melbourne), high winds (over 100 km/h), and low atmospheric humidity levels (6%) at a time when Victoria was tinder dry. The subsequent Victorian Bushfires Royal Commission determined that many of these fires, including one of the most damaging, were caused by electrical infrastructure . These fires were estimated to have an economic cost over AU$4.4B .
Societal and financial impacts of this magnitude are very significant in relation to the regulated asset base of the Australian Transmission and Distribution Network Service Providers. Understanding the risk associated with such high impact low probability events is critical, yet extremely challenging for large, geographically dispersed network assets. The Directors of these businesses require a transparent view of bushfire risk management practices and their effectiveness. ElectraNet are attempting to achieve this by developing a bushfire risk model which links the potential causes, pivotal events and consequences of electrical Flashovers.
An example of the value of this Asset Management tool is the highlighting of the significance of fauna as a fire start risk. This was an unexpected result. The bushfire risk model allows an entire transmission line asset base to be risk ranked using bushfire risk cost per annum. The bushfire risk model can be used to prioritise risk mitigation efforts.
Keywords: Risk, Electricity Transmission, Bushfire, Wildfire, Bow-tie diagram, Flashover
-Dan Tombleson and Christian Nolden
Full report can be downloaded below: