By Nick Harmsen
The world’s biggest lithium-ion battery — built by tech billionaire Elon Musk’s company Tesla last year — has survived its first summer in South Australia’s mid-north.
Key points
- AEMO says the Hornsdale Power Reserve is capable of charging at a rate of 80 megawatts and discharging at 100 megawatts
- It has a storage capacity of 129 megawatt hours
- That means it could operate for about 75 minutes at full capacity
And according to a new report by the Australian Energy Market Operator (AEMO), it’s outperforming coal and gas generators on some key measures.
Here’s a look at how it’s performed and its potential impact on the future of power in Australia.
The big battery could stop another statewide blackout
In September 2016, South Australia was plunged into darkness when storms tore through transmission lines.
The faults in the transmission system prompted several wind farms to unexpectedly power down.
With that sudden loss of generation, South Australia immediately began drawing more power across the interconnector to Victoria, which overloaded and switched off.
The 100 MW output of the Tesla battery might appear small compared to South Australia’s peak energy demand of about 3000 MW, but its ability to quickly inject electricity within a fraction of a second is a large factor in its success.
AEMO is now working on a new protection scheme, and Tesla’s big battery will play a part.
It aims to detect high flows on the interconnector and trigger the battery to start discharging its full output as quickly as possible, while shedding power to homes and businesses if required.
And future batteries could also be a part of the scheme in the future.
The battery is capable of responding more quickly to problems than coal, gas or hydro
According to AEMO the speed, precision and agility of the battery is unprecedented in dealing with both major power system disturbances and day-to-day frequency variations.
And on December 18 it got the chance to prove it, when a coal generator in New South Wales tripped.
The battery was able to respond to the sudden loss of 689 megawatts of generation within a fraction of a second.
A gas or steam turbine might have taken minutes to respond and adjust.
The Hornsdale Power Reserve is registered to provide what is known in the power markets as Frequency Control Ancillary Services (FCAS).
FCAS requires providers to keep a little bit of power in reserve — which the market operator can use to help correct the supply/demand balance in response to minor changes in load or generation.
Some FCAS services are reserved for use in a major event — like a major power station fire, a transmission line tripping or a big industrial load switching off.
Until Tesla’s big battery switched on, FCAS services in Australia had only ever been provided by traditional coal, gas, diesel and hydro generators.
