June 2024

The installation of the Hunter Power Project’s SFC Buildings was a multidisciplinary team effort that required careful planning. The buildings weigh 24 tonnes each and were transported more than 1,500km on a three-day journey from Adelaide before arriving to site in August 2023. The installation took place in an area where Simultaneous Operations (SIMOPs) is vital and attention to detail is required. SIMOPs involves supervisor and trade interactivity on the ground for the coordination of effort and safety. This is a key milestone – unit 1 is on the critical path and is important to the project’s commissioning portion.

June 2024

The installation of the Hunter Power Project’s Fin Fan Coolers has been successful. These closed-loop cooling systems weigh 30 tonnes each and are essentially air-cooled heat exchangers (ACHE). The process fluid enters the ACHE through inlet nozzles, passes through the tube bundle, and exits through outlet nozzles, cooling down as it transfers heat to the surrounding air. The tube bundle is cooled from air forced through by fans driven via electric motors. At HPP, each gas turbine has a dedicated closed-loop cooling water system. These systems circulate demineralised water treated with corrosion-inhibiting chemicals to cool the following equipment:

• The generator
• Control oil
• Lube oil
• High-pressure purge air compressors

June 2024

In the civil space at the Hunter Power Project, most services – including trade waste, stormwater systems, oily water systems, fire ring mains, and mechanical services – are completed in the ground. All concrete slabs in GT1, GT2, and Balance of Plant areas are completed except for some minor pipe supports and trenches, infill slabs, and light pole foundations. The civil team will now work on the finishing touches to site with infill pavement slabs, earthworks for pavements, and remaining pits and bollards.

June 2024

All four Balance of Plant Tanks have been completed and passed their hydrostatic tests. This involved filling the tanks with water to ensure there were no leaks. Each tank is approximately 11 metres high, with an internal diameter of 15 metres, and has a capacity of 1.944 million litres. When full, the total weight of each tank is 1,993 tonnes. The Service Water Tank is for potable water used across the project, while the Demineralised Water Tank will hold demineralised water of extremely high purity for use in the power generation process. It took 46 B-double trucks delivering 42,000L of water each from Colongra Power Station to fill the Demineralised Water Tank (third from left in image). The total travel distance of this two-week process was 5,520km or HPP to Perth and almost halfway back. All four tanks will now be handed over to the commissioning team, who will start filling the remaining tanks with diesel to be used for commissioning of the turbine. These diesel tanks will hold the back-up fuel to keep the turbines going when gas is not readily available.

It requires teamwork, precision and specialised transport to get our huge Snowy 2.0 power station components safely to site. Delivery of the largest and widest loads occur at night for safety reasons and to minimise disruption to the public. Two prime movers pull and one pushes the 7.5 metre wide and 156-tonne spiral case, escorted by pilots and the police.

The Snowy 2.0 Cooma precast manufacturing facility hit another significant milestone and completed production of 100,000 of 130,000 tunnel lining concrete segments. More than 230,000m3 (or more than 550,000 tonnes) of concrete was used to manufacture these seven-tonne precast segments, installed by tunnel boring machines used on the Snowy project.

The project team celebrated a major power station construction milestone with the breakthrough blast of the machine hall cavern crown. The final three metres of rock were drilled and charged with explosives according to a precise blast plan. After the tunnels are cleared, the shotfirer arms the electronic blasting system which uses a unique electrical pulse to initiate firing of the explosives.

The breakthrough of the final three metres of the power station’s 223-metre long transformer hall cavern crown. Drill and blast methods are used to profile the curved cavern crowns (or ceilings) and break up the rock, which is mucked out and followed by surface scaling to remove any remaining loose rock. The exposed solid rock face is then supported with rock bolts and shotcrete.

Power station equipment manufacturing for Snowy 2.0 is in full swing. The bespoke components are being fabricated with precision and skill at one of our subcontractor Voith Hydro’s global production facilities in Shanghai, China. The six pumped hydro units will generate up to 2,200 megawatts of power for Australia’s electricity grid.

After completing the 2.8km main access tunnel (MAT) in 2022, TBM Lady Eileen Hudson started on her second tunnel excavation for Snowy 2.0 – the 6km tailrace tunnel, which will connect Talbingo Reservoir to the underground power station complex. The Lady Eileen was disassembled at the MAT and reassembled at the Talbingo adit with new components including a cutterhead, shields and main drive.

Work began in June 2023 to excavate the cavern complex 800m underground where Snowy 2.0’s power station will be located. The two main caverns being excavated to house the machine hall and the transformer hall are huge – about 1.5 times the length of Melbourne Cricket Ground and the equivalent of a 20-storey building in height.

A proposal to expand the Snowy Scheme and deliver 2,200MW of generation and 350,000MW/h of large-scale storage was announced in early 2017.

The iconic Snowy Scheme’s role as the battery of the National Electricity Market (NEM) would be ‘supercharged’ as part of plans to expand its pumped-hydro storage capability.

It would provide a clean-energy solution to the critical security and supply issues in the NEM and recycle water utilised for electricity generation. In this way it would give continuous supply when at times of peak demand, with no impact on the Scheme’s water release obligations.

A feasibility study was commissioned to explore the physical, technical and environmental requirements for expansion of pumped-hydro at sites across the Scheme. The study also looked at the potential output of new facilities and the costs associated with the project.