Hydro Tasmania has reached a significant milestone in its plans to reimagine the iconic Tarraleah hydropower scheme, publishing its preferred development option in a detailed preliminary business case.

The Tarraleah hydropower scheme has generated electricity for Tasmanians for more than 85 years. It must be replaced within the next 10 to 15 years due to declining efficiency and increased risk of failure.

Hydro Tasmania CEO, Ian Brooksbank, said it was an opportunity to ensure that the Tarraleah scheme would help power the state for many decades to come.

“Tasmanian demand for energy is growing, with consumption expected to double in the next 30 years. So, we need to get more energy from our hydropower infrastructure,” Mr Brooksbank said.

“At the same time, the electricity market is changing rapidly. With increasing amounts of wind and solar coming into the grid, power stations need to be more flexible, so they can start generating at the flick of a switch and fill in the gaps when the wind doesn’t blow, and the sun doesn’t shine.”

Hydro Tasmania conducted a rigorous analysis of five potential options, considering the social, environmental, commercial, and economic risks and benefits of each option.

The preliminary business case identified the preferred option: full redevelopment with a pressurised conveyance. Early estimates put the cost at around $1.05 billion in 2023 dollars.

“This option delivers the greatest capacity, storage, flexibility, and reliability for every dollar invested, while addressing environmental risks. Redeveloped, the Tarraleah hydropower scheme will deliver 30 per cent more energy from the same amount of water, not to mention 250 jobs during construction.”

“But we need to emphasise that the cost estimates are still very early. There is a good chance costs will go up as we progress detailed plans in the final business case. Ultimately, the real test of cost is going to market for construction contracts.”  

Mr Brooksbank said he wanted to be as open and transparent as possible throughout the planning process, understanding the Tasmanian public was keenly interested in the project.

“Planning for major infrastructure projects such as this takes years, and many things can change along the way. We commit to keeping Tasmanians informed about the project benefits, costs, and risks.

“We will only proceed with the project if it is economically feasible and delivers benefits for Tasmania.”

Essential works on the Tarraleah hydropower scheme commenced last year, with nearly 100 full-time equivalent roles from Hydro Tasmania, Entura and Hazell Bros working to construct a new water intake and upgrading Mossy Marsh Dam.

The Final Investment Decision to redevelop the Tarraleah hydropower scheme is expected in late 2024.

The project supports Hydro Tasmania’s Battery of the Nation vision to maximise Tasmania’s existing hydropower capacity and build pumped hydro at Lake Cethana.

Ends…

Media contact: Lyn Southon on 0409 722 359 or media@hydro.com.au

Key figures

The preferred redevelopment option of Tarraleah hydropower scheme would deliver:

• Peak capacity of 190MW (up from 90MW)
• Around 30 per cent more energy annually from the same water
• Greater operational flexibility
• Additional capacity available to provide fast back-up to wind and solar
• 250 jobs during construction