ElectraNet’s South Australian battery shows the way forward
The performance of one of Australia’s first big batteries has exceeded expectations, blazing a trail for large-scale storage across the National Electricity Market.
More than two years on from its commissioning, the ESCRI ElectraNet South Australian battery storage system at Dalrymple in South Australia has achieved all of its objectives and even returned the $12 million grant ARENA provided in 2017.
The concept for the 30 MW / 8 MWh battery emerged in 2013 as a way to store energy in a network with more renewables. The name ESCRI stands for Energy Storage for Commercial Renewable Integration.
Construction began in October 2017, with the site energised in April 2018 and commercial operation commencing in December 2018.
As one of Australia’s – and the world’s – first large-scale battery storage systems, the project has broken a lot of new ground.
As well as developing a first-of-its-kind commercial model to provide reliability, security and competitive market services, ESCRI created processes to navigate NEM registration, licencing and connection processes, paving a pathway for others to follow.
The project also delivered the largest autonomous regional microgrid, able to operate both connected to the NEM and also be islanded. In islanded mode, demand for electricity in the region is met entirely by renewables, with network regulation services provided by the battery. This has provided insights into what will be required to operate the South Australian electricity system with 100 per cent renewable energy.
The system is charged by AGL’s existing 90 MW Wattle Point Wind Farm and surplus rooftop solar and is able to provide back-up power in the event of any interruption to supply from the grid.
Leading by example
After completing extensive feasibility, design and construction works, the third phase of the project has focused on the commercial operation of the Electranet South Australian battery.
The operational phase has shown how a large-scale battery can provide benefits to the network and energy market, as well as demonstrating a contracting and ownership that provides the most possible value.
ElectraNet says they have also tested how transmission network operators regulate battery owners, while also helping to establish pricing for grid-connected battery services.
The operation of the battery has also played a role in tackling technical and regulatory barriers to the deployment of these systems, helping to benefit other developers that have entered the market since.
The system has supplied Fast Frequency Response (FFR) ancillary services into South Australia, reducing constraints on the Heywood interconnector and delivering increased flows.
The battery has reduced the amount of unserved energy to the region following losses of supply, while also trading electricity into the NEM and supplying important frequency control ancillary services to help manage voltage in the grid.
Making an impact
In the two years from December 2018 to 2020, the ESCRI battery was called on in 29 system events, responding almost instantly to inject power to arrest dips in voltage or reduce the duration of an outage.
One event in December 2019 saw lightning cause a nearby powerline to trip. In this event, the battery maintained Dalrymple’s energy supply until the issue was resolved, showing how the system can enhance reliability for the region.
Weeks later, a catastrophic failure tripped a series of transmission lines. On this occasion, the battery responded immediately, supporting the network to recover from the sudden voltage dip to become stable within 2.5 seconds.
The arbitrage and FCAS markets provided revenue streams for the battery, allowing battery operator AGL to return the $12 million ARENA provided to the project.
FCAS revenue peaked in the six months from December 2019 to June 2020, earning $15.6 million in addition to $102,000 discharging revenue, from a $76,000 charging cost.
Over the two years from December 2018 to December 2020, the system earned $22.6 million in FCAS revenue and $319,820 in discharging revenue, from $329,750 in charging costs.
Blazing a trail
Since construction began on the ESCRI system, investment in large-scale batteries has accelerated sharply. ARENA has now supported the development of five battery storage systems, as well as the expansion of South Australia’s Hornsdale Power Reserve.
In early 2020, AEMO forecast battery costs falling faster than initially expected, predicting 5.6 GW of battery storage to come online by 2036-7.
The size of battery systems is also growing, with the Victorian Government recently announcing a plan for Neoen to build a 300 MW battery near Geelong, and CEP Energy planning the world’s largest battery for the NSW Hunter Valley with a capacity of up to 1200 MW.
Read more about ARENA’s portfolio of large-scale battery projects.