2 Case study – South Australian black system event People become used to reliable services and have little cause to stop to think about all the interdependent systems which function together so that, for instance, the traffic lights guide their commute out of the central business district, petrol is pumped into their car, and money can be paid with the tap of a card. This chapter is a short case study on the South Australia black system event which demonstrated how disruption to the delivery of one service – electricity supply in this case – can cascade through infrastructure networks to affect the delivery of many other services. This case study serves as a reminder of the need, in a modern society, for government and industry to work together to manage risks and build resilience.
2.1 Interdependencies In 2016 South Australia experienced a winter of extreme weather with flood events. Severe weather was forecast for and arrived on 28 September 2016. According to the Australian Energy Market Operator, tornadoes damaged electricity transmission lines, faults grew, and automatic mechanisms acted to protect assets.6 These factors led to an imbalance between supply and demand which caused a loss of electricity supply to South Australia. Eight hundred and fifty thousand customers lost electricity supply, affecting households, businesses, transport, community services and major industries. The review by Burns, Adams and Buckley7 includes a sobering reminder of the dependence on electricity: Electricity is, with few exceptions, integral to all our systems, needs and requirements as a modern society. The loss of power quickly impacts upon essential services, critical infrastructure and the very fabric of our society. Electrical power is often taken for granted but modern society (at all levels) is heavily reliant and dependent on it. While electrical power was restored to Adelaide within several hours, large areas of South Australia remained without power for several days. The review describes specific effects and consequences of the black system event in some detail and demonstrates the interdependencies between services. It was about an hour before the end of normal business hours on a Wednesday afternoon when the power went out. Transport signals and many traffic lights stopped working and the Traffic Management Centre lost the ability to observe and control intersections. As a result, police personnel were used to control key intersections in the difficult weather conditions.
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Black System South Australia 28 September 2016, published March 2017 Final Report of the Independent Review of the Extreme Weather Event South Australia 28 September-5 October 2016, January 2017 7
