Feasibility study - Tarraleah hydropower

Client: Hydro Tasmania
Location: Tarraleah, Tasmania, Australia
Date: May 2018 – ongoing

Exploring the feasibility of redeveloping an ageing hydropower scheme to better serve the future electricity market

Background

Tasmania’s iconic Tarraleah hydropower scheme (100 MW) was constructed in the late 1930s and is one of Hydro Tasmania’s oldest hydropower schemes. Located in the headwaters of the Derwent and Nive catchments, it remains vitally important to Tasmania’s energy security to this day as it regulates flows to the Derwent system of dams and hydropower station as well as water supply to Hobart.

With the scheme nearing end-of-life, substantial expenditure would be required to ensure safe and reliable generation into the future. This feasibility study is assessing options to redevelop the scheme with additional operational flexibility and capacity to better suit the anticipated requirements of the future electricity market.

This project forms part of Tasmania’s ‘Battery of the Nation’ initiative to support the transition of the Australian market to more wind and solar generation, which will require dispatchable renewables such as hydropower to smooth supply and to provide vital grid support services.

The feasibility study follows a pre-feasibility study conducted in 2017–18. It is co-funded by the Australian Renewable Energy Agency (ARENA).

Solution

Entura is working collaboratively with the owner (Hydro Tasmania), expert reviewers, equipment and material suppliers and contractors to develop an appropriate technical solution with a good understanding of project risks, costs, schedule and possible procurement methods and with broad stakeholder support.

Outcome

Through regular communication with the project governance team and key external stakeholders, Entura is developing a solution that:

  • can be constructed with minimal impacts on the existing Tarraleah scheme
  • will have minimal environmental impacts
  • maximises surface infrastructure to reduce geotechnical risk
  • has manageable project risk
  • can be staged to adapt to asset risk and market uncertainties.