A hydroelectric station the size of the Sydney Opera House is starting to take shape almost a kilometre underground at Snowy 2.0—a massive pumped-hydro renewable energy megaproject currently under construction in New South Wales’ Snowy Mountains.
The team of more than 5,000 people working to bring Snowy 2.0 to life has begun permanent concrete pouring underground, setting the stage to assemble the project’s six turbines.
With excavation in the massive machine and transformer halls now more than 90% complete, engineering teams are turning their attention to the internal fitout of the power station.
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Crews are preparing to install major components, including massive inlet valves and spiral casings designed to channel water that will fuel the generators.
Excavation is complete for the six connector tunnels between the transformer hall and machine hall that will be packed with specialised electrical equipment to channel power from the six generators to high-voltage transformers and on to Australian homes and businesses.
Over the coming months, construction crews will place the first of more than 1,400 pieces of precast concrete that will house the power-generating kit, including transformers weighing more than 400 tonnes each.
Snowy 2.0 has also taken delivery of all six reversible turbines, while the project’s power-generating high-voltage transformers are currently undergoing final testing.
Snowy Hydro CEO Dennis Barnes said reaching this stage required an extraordinary level of logistical coordination, safety focus, and strict quality assurance.
“Fit-out in our underground powerhouses is an extremely precise and detail-oriented process,” he said.
“We’re building some of the widest and deepest power station caverns in the world.
“Transitioning into the fit-out phase of an underground station the size of the Sydney Opera House is a landmark engineering achievement that we’re all extremely proud of.”
Snowy Hydro is currently building Snowy 2.0—Australia’s largest committed renewable energy and pumped hydro storage project. The massive energy storage project is needed to support cheaper, cleaner, and more reliable power as ageing coal-fired generators retire.
Initially costed at $12 billion, Snowy 2.0 has been beleaguered by cost blowouts and delays. A further cost reassessment was announced in October 2025 but is yet to be released. Some experts believe the final price tag will exceed $20 billion.
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The Joint Committee of Public Accounts and Audit has commenced an inquiry into Snowy Hydro Limited’s management of the Snowy 2.0 project following a major project reset in August 2023.
After receiving advice from independent construction cost experts, Snowy Hydro said it was “considering the commercial and practical implications to inform its advice to the government”.
