Battery at Dalrymple keeps the power on for South Australia's Yorke Peninsula and feeding the wider energy grid

ElectraNet's ESCRI battery storage system at Dalrymple on South Australia's Yorke Peninsula.

Overshadowed by South Australia’s other bigger Tesla battery at Hornsdale, the 30MW/8MWh ESCRI ElectraNet battery storage system at Dalrymple, near Stansbury on Yorke Peninsula, earned enough revenue in its first two years of operating to return the $12 million in grant funding from the federal government ARENA(Australian Renewable Energy Agency) to set up the project.

ARENA said the ESRCI (Energy Storage for Commercial Renewable Integration) had earned $22.6 million in frequency control ancillary services (FACS) revenue and $319,820 in discharging revenue, between December 2018 and December 2020. Frequency control ancillary services are called on to fill emergency gaps in the energy grid supply.

The Dalrymple ESCRI, powered by AGL Energy’s 90MW Wattle Point wind farm, was also configured to allow “islanding” of the Yorke Peninsula, to keep the local lights on in case of grid problems elsewhere. The “grid-forming” inverter capabilities it pioneered on the main grid (the ability to use battery inverters to “create a grid”‘) were considered critically important, as they would be key to fashioning a renewables-based grid without synchronous generation.

The ESCRI  also supplied fast frequency response ancillary services into South Australia, reducing constraints on the Heywood interconnector linking South Australia and Victoria, and delivering increased flows, and reduced the unserved energy to the region after losses of supply. In the two years from December 2018, the ESCRI was called on in 29 system events, responding almost instantly to inject power to arrest dips in voltage or cut the length  of an outage.

One event in December of 2019 was lightning causing a nearby powerline to trip, with the battery maintaining Dalrymple’s energy supply until the issue was resolved. Not long after, a catastrophic failure tripped transmission lines. This time the battery responded immediately, supporting the network to recover from the sudden voltage dip to become stable within 2.5 seconds.

ARENA said the Dalrymple battery project had broken a lot of new ground by delivering Australia’s largest autonomous regional microgrid, able to operate both connected to the NEM (national energy market) 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% renewable energy.”