CS Energy’s Wivenhoe Power Station recently tested its capability to help restart the electricity grid if a widespread blackout occurred.
Major power system blackouts are rare, but when they do occur they can have a significant impact on the community, such as when South Australia blacked out in 2016.
Wivenhoe is one of a number of generators that have agreements with the Australian Energy Market Operator (AEMO) to provide what’s known as System Restart Ancillary Services (SRAS).
Wivenhoe has a contract for carrying out a ‘black start’ – restarting the power station without using any electricity from the surrounding electricity network.
Not all power stations can do a black start, but Wivenhoe’s design as a pumped storage hydro plant makes it ideally suited for the process, according to Wivenhoe Production Coordinator Sean McKinney.
“Wivenhoe generates electricity by cycling water between a lower reservoir and an upper reservoir,” Sean said.
“Because we always keep a backup supply of water in Wivenhoe’s upper reservoir, we have enough water stored to enable us to perform a black start.
“Wivenhoe Power Station is essentially a giant rechargeable battery because it can store water as potential energy to be used later when it is needed.”
Above: Wivenhoe Power Station.
As part of its contingency planning, AEMO requires contracted SRAS providers like Wivenhoe to regularly test their black start capabilities. Wivenhoe successfully carried out its most recent test on 17 May in a collaborative exercise involving CS Energy, AEMO, and Powerlink.
During a black start test, Wivenhoe is 'islanded' to the nearby Mount England Switchyard and temporarily disconnected from the local electricity distribution network.
“When we’re islanded we only have emergency lighting,” Sean said. “We then restart each of the generating units using a meticulously planned procedure to reconnect to the network.
“Once a unit is started, we need to control our frequency and voltage. In a real situation this would allow AEMO to restore electrical supplies to other power stations and gradually rebuild the network.”
Above: Hydropower Technical Officer Mark Todd and Electrical Engineer Leonard Nhokwara took part in the recent SRAS test at Wivenhoe Power Station.