Hydro Tasmania is redeveloping the Tarraleah hydropower scheme, with $123 million invested for upgrade works and to assess the viability of building a brand new scheme and power station.
The $123 million investment towards the upgrades included $65 million committed by the Federal Government.
Tasmanian civil construction company Hazell Bros was awarded the contracts for the first tranche of upgrade works projects.
The new intake at Lake King William and new 1km tunnel to the intake is in preparation for future replacement of the canals that feed the scheme. Upgrade works are also focused on an improved spillway at Mossy Marsh Dam and upgraded road infrastructure.
Queensland Minister for Energy and Renewables, Guy Barnett, said the Tarraleah hydropower scheme, in the Central Highlands, is an iconic part of Hydro’s 100-year history in Tasmania and well positioned to play a significant role as the Australian energy market rapidly transforms.
“These upgrade works are another positive step towards making Tasmania the renewables powerhouse of Australia through the Battery of the Nation’s hydropower upgrades and pumped hydro and the Marinus Link vision agreed to in a historic partnership with the Australian Government announced in October 2022,” Mr Barnett said.
Hydro Tasmania Chief Executive Officer, Ian Brooksbank, said that Tarraleah is an incredible piece of engineering.
On site at Lake King William to see progress first hand, Mr Brooksbank said that it was fantastic to see work well underway for progressing the vision for Tarraleah into action.
“The network of canals that have fed water from Lake King William to the station for decades will need to be replaced in future,” Mr Brooksbank said.
“What is happening now are important upgrade works to construct a brand new water intake and connecting tunnel to meet up with a future new water conveyance. Improvements to the dam at Mossy Marsh are largely completed and upgrading the local access road is also underway.
“There’s almost 100 full-time equivalent roles working on these upgrades across our people, our specialist consulting firm Entura and our contractors – that’s great news for the region and there’s more to come as plans progress.”
Redevelopment plans
$700 million in investment is planned to help redevelop the Tarraleah hydropower scheme. Many of the scheme’s components have aged and there are physical and operational constraints, making it unsuitable for the future demand for electricity.
The redevelopment could increase the output from 110MW to 190MW from the same amount of water and is currently being assessed for commercial viability, with a final investment decision due in mid-2024.
“The vision for Tarraleah is to redevelop the scheme to deliver the benefits that the future energy market will need and generate up to 250 jobs during peak construction,” Mr Brooksbank said.
“The redevelopment would boost capacity, better support the growth of wind and solar through faster, more flexible operation and generate around 30 per cent more energy from the same water.”
Hydro Tasmania has also started environmental approvals through the Federal Government, a vital part of the redevelopment assessment, allowing the public to comment on Tarraleah’s proposed future.
“Getting the views of the local community on Tarraleah’s future is important. We will continue to provide opportunities to talk directly with our team about what is ahead,” Mr Brooksbank said.
Hydro Tasmania’s feasibility study showed the Tarraleah scheme could be redeveloped to increase capacity and flexibility – all valuable requirements in a future electricity market. A great example of repurposing existing hydropower assets to better align to future market opportunities and to deliver more value to Tasmania from the same water resource.
“These benefits will be returned to all Tasmanians through dividends that help fund schools, hospitals, roads and other important services and infrastructure that we rely on,” Mr Barnett said.
The first 750MW Marinus Link cable will unlock flexibility in the existing hydropower system to provide the on-demand back-up needed. It also opens up potential for capacity upgrades in Hydro Tasmania’s assets including the Tarraleah scheme and the West Coast stations. The second Marinus Link cable creates the opportunity to develop a new pumped hydro scheme – a 750MW, 20-hour, cost-competitive, long-duration storage opportunity at Lake Cethana.
Benefits will flow back to Tasmania through access to affordable power, economic investment, creation of much needed jobs, attraction of new business, and increased profitability for Hydro Tasmania which brings revenue to the state government to support vital infrastructure and services.
The Marinus Link opened for international tender in January 2023.
