The Snowy 2.0 pumped-hydro mega project has reached another major milestone with the excavation and lining of a second tunnel completed at Lobs Hole in the Snowy Mountains, further accelerating the progress on Australia's largest committed renewable energy project. 

The Polo Flat segment factory based in Cooma produced all 13,140 concrete segments used to line the 2.93-kilometre emergency, cable, and ventilation tunnel (ECVT). This engineering and construction marvel follows the completion of the adjacent main access tunnel (MAT), which was completed late last year. 

The team continues to forge ahead with the next phase of construction– drill and blast excavation of the power station cavern. 

“We are extremely pleased the ECVT excavation has been completed, and the whole project team is excited to be moving into the next critical phase of construction. Our huge power station cavern will be located about 800 metres underground and will be one of the largest and deepest in the world,” – Dennis Barnes, Snowy Hydro CEO. 

Meanwhile, the 11-metre diameter, state-of-the-art tunnel boring machine (TBM) Kirsten is being modified to excavate the 1.45-kilometre inclined uphill pressure shaft, a world first. The modifications include altering the levels of the TBM’s tanks and mechanical equipment so they remain horizontal when travelling up the incline, and converting the walkways into steps and ladderways. The pressure shaft will be lined with the bespoke concrete segments. 

To allow for more efficient tunnelling, a screw conveyor will be installed to extract excavated rock from the cutterhead to a sandwich conveyor system with face-to-face rubber belts to reduce the risk of crushed rock spillage down the slope. 

Clough, as part of the Future Generation Joint Venture with Webuild and Lane, is delivering the civil and electro-mechanical works for the Snowy 2.0 Project, which is owned by Snowy Hydro Limited. The project will link two existing Snowy Scheme dams, Tantangara and Talbingo, through underground tunnels to the depths of up to one kilometre and an underground power station with pumping capabilities. 

Snowy 2.0 will add 2,000 megawatts of energy generation and provide 175 hours of energy storage for the National Electricity Market, enough to ensure the stability and reliability of the system during prolonged weather events, such as wind or solar droughts. 

Snowy Hydro already plays a critical role in ensuring system stability at times of peak demand, and Snowy 2.0 will enhance this existing capability and ensure that it continues to provide a secure and reliable transition to renewables.