South Australia experienced a damaging storm event over the weekend of 11 – 13 November. In this event, South Australia’s distribution grid — poles and wires — operated by South Australia Power Network (SAPN), and transmission network — towers and wires — operated by ElectraNet, suffered considerable damage as a result.
In that time, ElectraNet and SAPN – both members of the South Australian Business Chamber – have been working extremely hard to get power restored to those impacted by outages.
ElectraNet had two lines come down on the Heywood interconnector, the Victorian link. Consequently. we are not connected to the rest of the National Energy Market (NEM) which is called “islanded”. They expect the interconnector will be down but expect longer than a week. The conditions make it hard to get equipment into the area, including cranes and soft ground. There is also a lot of other work needed to be done after the tower is put back up.
SAPN had over 500 live wires down and prioritising making them safe rather than restoring service. There are still almost 1,800 customers without power today, down from 34,000 customers on Monday, down from 65,000 on Sunday. Due to the last three years of high rainfall – and the last three days – there was still a concern of further tree falls due to the soft ground. All their crews are out, and they have called in help from NSW.
Network stability was not at risk earlier in the week, but today will see the network tested as conditions are perfect for solar generation. Without the interconnector, the National Energy Market (NEM) cannot soak up our excess solar. This can lead to system instability which can lead to network outages.
This had led to the Australian Energy Market Operator (AEMO) working with SAPN and ElectraNet to curtail solar generation on SA’s energy network. This has begun with large scale producers. However, this may not be enough, causing SAPN to curtail solar generation from commercial, industrial, and residential generation. As a result, some customers may find that their solar has been “tripped off” and is not producing power.
This is not the first time South Australia has been islanded which and will probably not be the last. However, further redundancy is being built into the system. Project Energy Connect (PEC) is the second interconnector – NSW and Victorian link – currently under construction and will improve grid stability and reduce the risk of islanding in the future. This joint venture with TransGrid – NSW transmission line operator – has been fast-tracked on the SA side. ElectraNet is expecting the physical connection with NSW to be completed in 12 to 18 months.
