AGL is one of Australia’s largest integrated energy companies and has a long-standing presence in the Upper Hunter through its electricity generation and energy infrastructure. Read more about AGL's activities in the Upper Hunter at the AGL website.
Both projects are in the early development stages and a provisional timeline for their development is being prepared by AGL, including next stages, project approval, construction and when the projects would be operational.
Should the projects proceed to construction, they are expected to deliver approximately 1,400 construction jobs and 80 ongoing operations jobs.
The projects will not impact the operations of Glenbawn or Glennies Creek dams or the security of downstream entitlements.
For more information on the AGL projects, email AGLCommunity@agl.com.au or call 1800 039 600.
Frequently asked questions
What are the projects?
AGL is proposing two large pumped hydro projects, with the opportunity for integrated wind energy, at WaterNSW’s Glenbawn and Glennies Creek reservoirs in the Upper Hunter.
Each site would include a pumped hydro energy storage project and potentially a co-located wind development.
The pumped hydro projects would include a purpose-built upper reservoir connected to WaterNSW’s reservoir, as the lower reservoir, through underground tunnels and power station. The projects would pump water to the upper reservoir during periods of excess energy in the market and release water down through the power station to generate electricity when needed by the market.
The projects would essentially function as a large natural battery, using water to store and generate energy. Electricity storage projects such as this are critical to support solar and wind power as old coal fired power stations close in coming years.
Who will own the projects?
The projects would be developed and funded by AGL, not the NSW Government or WaterNSW. This would include management of the environmental assessments and approvals, construction and operation of the project.
Upper Hunter Hydro had originally been selected by WaterNSW through a competitive tender process in February 2024 to develop the projects as part of WaterNSW’s Renewable Energy and Storage Program. AGL acquired 100 per cent ownership of the projects in May 2025.
What benefits will the projects deliver?
- Long duration storage is critical to support the State’s transition to a clean, affordable and secure energy supply.
- Should the projects proceed, they will support regional development through approximately 1,400 construction jobs and 80 ongoing operational jobs.
Is AGL developing wind farms as well as pumped hydro?
In addition to the pumped hydro projects, AGL will also investigate the viability of co-located wind farms as part of an integrated energy project. AGL is at the very initial stages of their investigations.
Are the projects located in a Renewable Energy Zone?
The proposed projects would be located within the Hunter - Central Coast Renewable Energy Zone. If constructed, the pumped hydro projects will provide significant long-duration storage and support renewables development in this region.
When will work on the projects commence if approved?
Both projects are currently in the early development stages and a provisional timeline for their development is being prepared by AGL, including next stages of development, project approval, construction and when the project’s would be operational.
How is WaterNSW involved?
WaterNSW has granted access to areas of its land to support the planning and assessment of pumped hydro energy storage (PHES) projects at Glenbawn and Glennies Creek. These sites were originally identified and progressed by Upper Hunter Hydro Pty Ltd (UHH), which was selected by WaterNSW through a competitive tender process. WaterNSW approved the transition of the projects to AGL in May 2025.
The agreement with AGL requires them to work closely with WaterNSW as the projects progress.
Will the water required for the projects affect the amount of water available for irrigation or as drinking water? What about in times of drought or flood?
The projects will not impact the security of downstream entitlements or WaterNSW operation of Glenbawn or Glennies Creek dams. This is largely a function of the relatively small volume of the project’s upper reservoirs and that the water is cycled between the upper and lower reservoirs, resulting in minimal losses.
UHH is designing the projects to tolerate periods of drought. The projects will not impact on WaterNSW's operation of Glenbawn or Glennies Creek dams during flood events.
About pumped hydro and WaterNSW
Why is WaterNSW considering renewable energy projects on its land and assets?
As a State-owned organisation, WaterNSW sees the renewable energy projects as a opportunity to work with the NSW Government to help achieves its energy and emissions objectives, including those set out in the NSW Government Electricity Strategy and Net Zero Plan.
It’s also an opportunity to work with the private sector to also bring jobs and training opportunities to regional NSW and put downward pressure on costs for both WaterNSW and energy customers.
How does pumped hydro work?
Pumped Hydro Energy Storage is a highly efficient and reliable method of storing and generating electricity and can play a crucial role in NSW’s transition towards a more sustainable and renewable energy future.
Pumped Hydro Energy Storage harnesses the power of gravity and water to store and generate electricity efficiently.
Water is pumped uphill from a lower storage reservoir to an upper reservoir through underground tunnels using energy sources such as those provided by renewable energy technologies. This water may then be released back down at appropriate times to generate renewable electricity, via power generating turbines.
By using the movement of water to produce renewable energy, it can be stored and used when needed. Pumped Hydro Energy Storage may therefore be thought of as a large water driven battery.
Would the proposed projects impact each region’s water security?
No, the proposed projects will not impact the region’s water security.
Water required by each project, should they proceed, would be utilised in a continuous loop, rather than lost. The amount of water being cycled will be less than 0.5% of the volume of the water storage dam, much less than the amount lost from the lake each year through evaporation (around 2-3%).
How would the projects access water at a WaterNSW dam?
PHES projects operate as a ‘closed loop’ system. This means water is continuously cycled between an upper and lower reservoir during operation. The only water taken from a WaterNSW dam is for the initial fill and to top up small losses from evaporation and operations.
Since the same water is reused, PHES projects don’t need a water access licence to move water between their reservoirs. However, any water they do take must comply with the Water Management Act (2000). Like all water users, they must ensure their water use doesn’t impact existing licence holders or the State’s Sustainable Diversion Limits.
Would there be property acquisition?
No. Each proposed project is being delivered by a private developer, and private developers are not permitted to compulsorily acquire property. The developers would engage with neighbouring properties as required.
Will new electricity transmission lines (poles and wires) be required?
WaterNSW is the owner of the land and is not responsible for determining transmission line requirements. During the planning process all Developers would seek to optimise their planned transmission route. Existing routes and likely to the used where possible and any new routes would be carefully selected to minimise visual impacts and avoid sensitive areas. Contact EnergyCo for more information on this process.
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