The New South Wales government has given the green light to two significant battery energy storage systems (BESS) this week, committing an estimated AUD$2 billion in new energy infrastructure. The approvals for the Tomago BESS near Raymond Terrace and the Mt Piper BESS near Lithgow mark a critical step in the state’s transition away from coal-fired generation and towards a more stable, renewable-powered grid.
Announced on June 11, 2026, these large-scale projects are poised to bolster the National Electricity Market (NEM) by providing essential firming capacity, allowing greater integration of intermittent wind and solar power.
Tomago BESS: Powering the Hunter
The Tomago Battery Energy Storage System, to be developed by AGL near Raymond Terrace, will contribute 500 MW of power capacity and 2,000 MWh of energy storage. This translates to enough capacity to supply approximately 200,000 homes during peak demand periods.
The project represents an investment of AUD$1 billion and is strategically designed to support the Hunter-Central Coast Renewable Energy Zone (REZ). During its construction phase, the Tomago BESS is expected to create 200 jobs, with a further six ongoing operational positions once complete. AGL has also committed to a $2.2 million Voluntary Planning Agreement with Port Stephens Council for community improvement initiatives.
Minister for Planning and Public Spaces, Paul Scully, highlighted the scale of the investment:
“With a $1 billion price tag, this battery is one of the biggest in NSW and injects a major capital investment within the Port Stephens and Lower Hunter areas.”
Mt Piper BESS: Strengthening the Western Grid
The second major approval is for the Mt Piper BESS, located near Lithgow. This project also represents an estimated AUD$1 billion investment and is expected to generate up to 177 construction jobs. While the specific power and energy capacity for Mt Piper BESS were not explicitly detailed in the recent announcement, its substantial investment value indicates a similar large-scale contribution to grid stability.
The Mt Piper project is intended to integrate with existing infrastructure, mitigating the need for additional transmission lines. It complements EnergyAustralia’s broader energy transition plans, including the Lake Lyell Pumped Hydro Project, which is currently in its feasibility stage.
A Critical Step in NSW’s Energy Transition
These approvals underscore New South Wales’ urgent need for dispatchable energy storage as the state’s coal-fired power stations progressively retire. Batteries like Tomago and Mt Piper can store excess renewable energy generated during periods of high sun or wind and discharge it when demand peaks or renewable output is low, thereby stabilising the grid and reducing reliance on fossil fuels.
The deployment of such large-scale battery systems is crucial for maintaining system strength and ensuring a reliable power supply. The state’s energy roadmap has identified a significant requirement for long-duration storage to meet future demand, particularly as the generation mix shifts towards renewables. Homeowners considering their own energy independence can explore options for residential systems, detailed in guides like Unlock $3,700+ in Rebates: Your 2026 Guide to Australian Home Battery Systems.
Project Comparison
| Feature | Tomago BESS | Mt Piper BESS |
|---|---|---|
| Developer | AGL | EnergyAustralia (implied, complements plans) |
| Location | Near Raymond Terrace, Hunter-Central Coast REZ | Near Lithgow |
| Investment | AUD$1 billion | AUD$1 billion (estimated) |
| Capacity | 500 MW / 2,000 MWh | Large-scale (specific MW/MWh not yet detailed) |
| Construction Jobs | 200 | 177 |
| Operational Jobs | 6 | Not specified |
| Key Role | Support Hunter-Central Coast REZ | Integrate with existing infrastructure, complement Lake Lyell Pumped Hydro |
Broader Implications for the NEM
The rapid deployment of grid-scale batteries across Australia is a testament to their increasing importance in the NEM. Just yesterday, RWE officially opened Australia’s first 8-hour battery storage system in NSW, the Limondale BESS, further diversifying the state’s storage capabilities. These projects, alongside the ongoing development of Renewable Energy Zones, are fundamental to achieving Australia’s ambitious emissions reduction targets and ensuring energy security. For those interested in optimising their energy use at home, understanding options like Smart Home Energy Systems: Slash Your 2026 Australian Electricity Bills by Up To 30% can also play a role in reducing overall grid demand.
The approvals for Tomago and Mt Piper BESS represent concrete progress in building the resilient, renewable-powered energy system that NSW requires. They signal continued confidence in large-scale battery technology as a cornerstone of Australia’s future energy landscape.