Western Downs battery is a 200 MW storing up to 400 MWh of energy with up to 2 hrs of power in reserve.

It is a grid-scale battery which will leverage leading-edge technology, connecting into Australia’s national electricity grid via the transmission network.

As an industrial sized battery energy storage system, the battery will provide grid stability by dispatching stored energy to the grid during peak times of demand.

What Can a Big Battery Do?

Like a Swiss army knife, a big battery can do many things.

Basic function

When there is excess energy , the battery will charge. When there is high demand for energy, the battery will discharge.

Frequency support

To maintain the stability of the system, the grid has frequency control. The battery injects electricity in response to frequency changes. The battery will also add competition to the markets which helps reduce consumer electricity prices, helping to reduce electricity costs.

Virtual Inertia

As with vehicle suspension on an uneven road, inertia services are essential for stabilising the grid. A big battery can enable the advanced power inverters to emulate the existing inertia services being supplied by an ageing fleet of fossil fuel power plants. This service is currently being trialled at Hornsdale Power Reserve.

Network support

Grid-scale batteries can provide dynamic warp-speed responses so existing transmission lines can operate at full capacity. Like adding another lane to a freeway, the battery can unlock additional capacity on existing transmission networks – saving customers millions of dollars in expensive transmission line upgrades.

Firming renewables

Along with wind and solar technologies, large-scale batteries help to firm variable renewable energy. Batteries are an essential component in the stable transition to clean electricity and achieving emissions reduction targets.


Neoen are leading the way in delivering big batteries in Australia and around the world.

Neoen’s 150MW Hornsdale Power Reserve , more commonly as the ‘Tesla Big Battery’, has been keeping the lights on and electricity costs low for South Australians, since 2017.

Our 300MW Victorian Big Battery, currently under construction near Geelong, will be one of the world’s largest batteries.