Deployment of battery energy storage in Australia’s NEM is now happening at speed. In 2025, the BESS sector jumped from 2 GW to 5.6 GW of commercially operational capacity, and this deployment rate is expected to continue through 2028.

So, as the NEM transitions from BESS being 5% of peak demand to almost 40%, what should you be thinking about if you’re investing in BESS in the NEM?

This article summarises the recent keynote presentation at Energy Storage Summit Australia. The full slide deck can be found at the bottom of the article.

BESS deployment in the NEM is now world-leading

• The 5.6 GW of operational BESS capacity reached at the end of 2025 represents 16% of peak demand.
• This now rivals major global BESS markets ERCOT and GB, and sits only behind CAISO.
• Based on projections for capacity growth in the next two years, this will increase to 38% in the NEM - an unprecedented level of BESS penetration globally.

This is already having an impact on the system

• BESS exports now regularly exceed 2.5 GW in the evening peak - directly offsetting gas and coal generation.
• This has a significant benefit for consumers: lower peak prices and reduced carbon emissions.
• But it also reduces the prices available to batteries to discharge at, cannibalising revenues.

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