Hydro system improvement

 

Tarraleah

Improving and optimising our existing hydropower generation is a key part of the Battery of the Nation initiative. The flagship project we’re currently assessing focuses on one of Tasmania’s oldest hydropower schemes.

The Tarraleah scheme in the Central Highlands was commissioned in the 1930s and produces around 630 gigawatt hours of energy each year (or 6.5%) of Hydro Tasmania’s total production.

With the support of the Australian Renewable Energy Agency (ARENA), we’re assessing options for redesigning the Tarraleah Power Scheme.

ARENA funded a pre-feasibility study, looking at how the hydropower scheme might be repurposed for a future energy market. This study recommended a full feasibility study to assess risks and benefits of scheme redevelopment in comparison to progressive refurbishment.




The next steps

 

ARENA has now provided $2.5 million, matched by Hydro Tasmania, for a feasibility assessment into upgrading or replacing the Tarraleah Power Station. The project would also improve other parts of the Tarraleah scheme.

The proposal would more than double the scheme’s capacity from 104 megawatts (MW) to 220 MW – contributing to the overall boost of 2,500 MW planned for Tasmania under Battery of the Nation.

Replacement would also transform the Tarraleah Station into a state-of-the-art hydropower asset, perfectly suited for Australia’s changing energy system.

By converting the station to flexible operation, instead of just base load, it could flexibly boost output at times of high market demand.

Feasibility work into the preferred option (upgrade or replace) is expected to take about 18 months.

The redevelopment could cost up to $500 million over three years, and support hundreds of engineering and construction jobs in the Derwent Valley and across Tasmania.


M strathgordon-power-station-55

Gordon Power Station


This station is our largest. To maintain environmental flows to the Gordon River, we are currently running an existing large turbine at low load, which is not efficient.

We have investigated a solution to more efficiently generate power from the environmental water flow released to the Gordon River using a smaller turbine designed for these flows.

Our feasibility study demonstrates that the addition of a smaller turbine is both technically and commercially feasible. Implementation of the project would bring a number of benefits including:

  • assist in prolonging asset life by running the existing turbines more efficiently
  • increasing annual energy generation from the same amount of water released.

The project has been prioritised against other business capital expenditure needs and will not be proceeding to implementation at this stage.

However, the future market is changing. Hydro Tasmania will continue to monitor the market for changes that may further improve the value of the project and trigger a review of current capital expenditure priorities.


Improving the hydropower system


In addition to these projects, we are continuing major refurbishment and upgrade works around the state that support Tasmania's plan to become the Battery of the Nation.

Asset upgrades will also be vital to boosting generation and efficiency.

© Hydro-Electric Corporation 2018