Pumped hydro potential for Tasmania


Coal is retiring, and as new sources of renewable energy like wind and solar are cheap and becoming more plentiful we need to maintain energy reliability, stability and security by investing in dispatchable capacity.

Pumped hydro will form a huge part of that. It represents the next generation of Tasmanian hydropower, and lets us re-use our hydro water again and again to create clean energy.

Our studies have found huge pumped hydro development potential in the state – the 14 options represent around 4800 megawatts of reliable, cost effective capacity. Lake Cethana, Lake Rowallan and Tribute have emerged as the most promising pumped hydro sites in Tasmania following studies done over the past 20 months looking at the state’s potential.

These outcomes further strengthen the case for more interconnection across Bass Strait, which would also unlock Tasmania’s renewable energy potential in both our existing hydropower system and future development potential.

Below is further information about the pumped hydro project. We encourage you to contact us for more information and to ask any further questions. 

What are the three most promising sites?

Three most promising pumped hydro sites

The map shows the three sites - at Lake Cethana and Lake Rowallan in the North West, and near Tribute Power Station on the West Coast – which were selected from the original list of 14 potential pumped hydro options around the State.

There is 1700 MW of potential capacity in total for these three sites, and the storage duration ranges from many hours to well over one full day.

The outcome of the more detailed studies will be a preferred project that could be taken forward and be ready to operate when 1200MW of additional Bass Strait interconnection comes online.

In the Mersey-Forth region:

 Mersey-Forth: Lake Cethana    
 Detail Capacity (MW)  Storage (Hours) 
 

Construction of a new upper storage that connects via an underground tunnel to Lake Cethana, which would be the lower storage.

An underground power station between the two storages, connected by underground water conveyances (tunnels).

 600  12



 Mersey-Forth: Lake Rowallan    
 Detail Capacity (MW)  Storage (Hours) 
 

Construction of a new upper storage that connects via an underground tunnel to Lake Rowallan, which would be the lower storage.

An underground power station between the two storages, connected by underground water conveyances (tunnels).

 600  24
 

Pumped hydro - connect existing lake to new upper storage
The illustration at left shows how existing lakes can be connected to new upper storages.

On the West Coast:

 West Coast: Tribute pumped hydro    
 Detail Capacity (MW)  Storage (Hours) 
 

Connecting existing storages – Lake Plimsoll as the upper storage and Lake Murchison as the lower storage. 

A new underground power station and new underground water conveyances (tunnels), constructed adjacent to the existing underground power station.

 500  31


Pumped hydro - linking existing storages

The illustration at left shows how existing lakes can be connected.

Why were these three options selected?

The three selected sites stacked up as the most promising when we assessed them against a range of technical, environmental, financial and social criteria as part of the studies carried out over the last 20 months to assess Tasmania’s pumped hydro potential.

These sites represent strong and sustainable development opportunities. There’s 1700 megawatts of potential capacity in total across these three options and the storage duration ranges from many hours to well over a full day.

This puts Hydro Tasmania in a great position to select one strong development opportunity that can be ready for more interconnection.

What happens next?

The next stage involves a more intensive feasibility study to gather more detailed information and assess the suitability of each of the sites for development. This stage will involve engagement with local communities.

The outcome of this work will be a preferred project that could be taken forward and be ready to operate when 1200MW of additional Bass Strait interconnection comes online.

We’ll be getting out to the communities in these areas again, to let them know more about the process, how they can be kept informed and consulted, and what to expect in coming months.

What are the remaining pumped hydro options?

State wide pumped hydro_FINAL

 

Pre-feasibility work will continue on these sites as the three selected sites progress to feasibility stage.

We expect to finalise pre-feasibility studies later in 2019 and will take into account the work that will be done on the three most promising sites.

The outcome from the remaining 11 pre-feasibility studies is a pipeline of potential future pumped hydro projects that can deliver 2500MW of capacity and be developed in stages as the electricity market transitions.

In the Mersey-Forth region, we’re looking at the following pumped hydro options.

Regional maps - Mersey Forth_FINAL
 Mersey-Forth: Lake Cethana Options   
 Detail Capacity (MW) 
 New link between Lake Gairdner (upper) and Lake Cethana (lower)   270
 Convert Cethana Power Station to pumped hydro   100
 Convert Lemonthyme Power Station to pumped hydro  54
 Convert Wilmot Power Station to pumped hydro  32

Mersey-Forth: Lake Parangana option     
Detail Capacity (MW)
New upper storage and new link to Lake Parangana (lower)                300




On the West Coast of Tasmania, we’re looking at the following pumped hydro options.

Regional maps - West Coast_FINAL

West Coast: Lake Murchison options   
Detail Capacity (MW) 
Convert Tribute Power Station to pumped hydro                                   84

West Coast: Lake Margaret options   
Detail   Capacity (MW) 
New link between Lake Margaret (upper) and Lake Burbury (lower)    800
New upper storage and new link to Lake Margaret (lower)  300

West Coast: Lake Rosebery option   
Detail Capacity (MW) 
New upper storage and new link to Lake Rosebery (lower)                   400


In the state’s central region, we’re looking at the following pumped hydro options.

Regional maps - Central Region_FINAL
Derwent: yingina / Great Lake option   
Detail Capacity (MW) 
New lower storage and new link to yingina / Great Lake (upper)  600

Derwent: Lake Echo option   
Detail Capacity (MW) 
New upper storage and new link to Lake Echo (lower)                  200

How does pumped hydro work?

  • Pumped hydro energy storage systems have an upper and lower reservoir.
  • The water is stored in the upper reservoir, ready to use when electricity is needed. When demand is high and supply is needed, the water can be run through a turbine to the lower reservoir, generating electricity.
  • The water in the lower reservoir gets pumped back uphill when there is excess electricity in the system (which often happens with wind and solar).
  • Our short video explains how it all works!
Pumped hydro infographic_FINAL

Why do we need pumped hydro?

  • More than 70% of Australia’s power currently comes from coal-fired power stations that are likely to close in the next few decades.
  • Wind and solar are becoming the dominant sources of new energy but they are variable. That’s simply because the sun doesn’t always shine and the wind doesn’t always blow.
  • That means energy storage will be crucial in the future, to help balance wind and solar energy in the system and ensure energy is reliably available when consumers need it. 
  • Tasmania has natural advantages in developing pumped hydro because we have existing assets and storages, just waiting for the ‘add on’.

What’s in it for Tasmanians?

  • Battery of the Nation is about locking in our island’s energy security and giving Tasmanians the lowest possible power prices.
  • Battery of the Nation is not a Hydro Tasmania initiative; it’s a Tasmanian initiative. It’s designed to serve and support our communities, and will involve opportunities and contributions from right across the renewable energy sector.
  • Our analysis shows Battery of the Nation would create billions of dollars of investment and thousands of jobs in regional Tasmania over 10 to 15 years.
  • Doubling Tasmania’s clean energy would also create a surplus, beyond the state’s own needs, to support mainland Australia. That’s crucial to replace the coal power that’s being phased out.

Why is more interconnection important?

  • More interconnection makes all of this viable - allowing Tasmania to get its product to market. Even with the cost of developing further interconnection, our analysis confirms Battery of the Nation is a front-runner that’s extremely competitive and cost-effective.
  • TasNetworks has now released its Initial Feasibility Report considering a second Bass Strait electricity interconnector, Marinus Link, finding it is technically feasible and economically viable. The report found “it would be a strategic interconnection investment providing NEM-wide economic benefits”.
  • The release of the report coincides with the Federal Government’s announcement of $56 million to accelerate the delivery of Marinus Link.
  • You can read more about the initial feasibility assessment for Project Marinus and also review the Tasmanian Government’s Current Situation Assessment paper in relation to both Marinus Link and Battery of the Nation.

Are you considering projects in the World Heritage Area? 

  • No, we have excluded the environmentally sensitive Tasmanian Wilderness World Heritage Area (TWWHA) and National Parks from our pumped hydro studies. There will be no pumped hydro sites developed in the TWWHA.

Are you planning to dam any more rivers?

  • No, we are not investigating new on-river dams as part of any potential pumped hydro project.
  • There is potential for development of new small off-river storages to support pumped hydro schemes.

How can I provide feedback?

  • We welcome views from the Tasmanian community and will continue to keep you informed as studies progress.
  • We welcome your suggestions on the best way to provide project updates or for you to contact us with questions you may have.
  • Send your feedback to batteryofthenation@hydro.com.au or call 1300 360 441

 

 

 

 

© Hydro-Electric Corporation 2019