In December’s Snowy 2.0 update, Snowy Hydro CEO Dennis Barnes recaps progress and key events throughout the last 12 months.
The review and reset of the pumped-hydro Snowy Scheme expansion project has been a major milestone in 2023.
The reset has put Snowy 2.0 on a robust and sustainable footing, with new contract arrangements in place and a revised cost of $12 billion. The full commercial operation date for the new 2,200 megawatt power station is December 2028.
The focus for the project is prioritising safety and environmental outcomes while achieving construction program targets.
Meanwhile tunnel boring machine (TBM) Florence is underway again at Tantangara after a significant period paused in soft ground conditions after a surface depression formed above the cutterhead. Following an extensive process of ground stabilisation, the project has recently received NSW government approval for a planning modification, enabling the machine to restart tunnelling the headrace adit.
Progress highlights for 2023 include TBM Lady Eileen Hudson being relaunched in July to excavate her second tunnel for the project – she’s now one kilometre into the tailrace tunnel.
There are more than 2,700 people employed on Snowy 2.0 and a total of 20 million hours have been worked to date.
Drill and blast excavation of the power station cavern crowns is well underway from both ends of the machine and transformer halls and we’re seeing large power station components manufactured by Voith Hydro delivered to site.
Senior electrical quality engineer Victor Teo is in Shanghai, China, where Voith is fabricating some of the key electrical components for Snowy 2.0, including stator bars, rotor bars and poles.
The stator bars are bent to a precise shape and highly specialised insulation tape is applied by both machine and technician. These bars are part of the generator which is connected to the transformer to deliver electrical current.
Insulation resistance and short circuit tests are conducted on every bar to ensure compliance with our engineering requirements and Australian Standards.
468 stator bars are needed for each of the six pump-turbine generator units, so over 3,000 of them including spares will be produced.
There is always a member from the Snowy Hydro team in China to conduct quality assurance activities, monitor progress, act as a conduit to close out technical issues and to conduct Factory Acceptance Tests
Snowy 2.0 project manager and environmental engineer Emily Martin is at Tantangara, where TBM Florence is tunnelling in slurry, or closed, mode. This mode utilises the onsite slurry treatment plant and allows the team to pressurise the ground around the TBM to provide additional stability.
The intake excavation works at Tantangara are progressing well, with stage 2 well underway.
This involves another 78,000 cubic metres of drilling and blasting earthworks, along with rockbolt installation and shotcreting.
The intake excavation, which is where water will enter the headrace tunnel, is currently about 35 metres deep and it will be extended to a total depth of 55 metres.