News

SNOWY 2.0 PROJECT UPDATE – JANUARY 2024

31/01/2024

Deep underground at Lobs Hole in the Snowy Mountains is the heart of Snowy 2.0, the pumped-hydro expansion of the mighty Snowy Scheme. It’s where we’re building a huge power station complex that will house equipment capable of generating 2,200 megawatts of renewable energy.

In this month’s update we’re celebrating a major power station construction milestone – the breakthrough blast of the machine hall cavern crown.

With excavation of the crown – or ceiling – of the cavern taking place from both ends, the final three metres of rock are drilled and charged with explosives according to a precise blast plan.

The tunnels are cleared and the shotfirer arms the electronic blasting system which uses a unique electrical pulse to initiate firing of the explosives.

According to Snowy 2.0 project director Dave Evans, the machine hall achievement signals further progress after the recent transformer hall cavern crown breakthrough and restart of tunnel boring machine Florence in the headrace tunnel at Tantangara.

“These milestones are only possible with the whole team working together as one, whether they are subcontractors like Orica, the company managing underground blasting operations, or the lead contractor Future Generation and Snowy working so closely together.”

To see the latest Snowy 2.0 project’s statistics, view the fact sheet here.

As the underground drill and blast works continue, the manufacturing of major hydropower components for Snowy 2.0 is also well underway.

Snowy Hydro senior quality engineer Victor Teo is based for part of the year in Shanghai, where Voith Hydro – the company producing major power station equipment for Snowy 2.0 – has a large facility.

He also travels to nearby cities including Zhuji and in his quality and compliance role, participates in factory acceptance tests and hold point inspections for components being fabricated by subcontractor Shenke such as the draft tube liners and cones, and the huge stator frames.

The draft tube liners funnel water into and out of the power station turbines and are comprised of six segments. They are 4.6 metres high, 30 metres long and weigh 40 tonnes when assembled.

The six stator frames that house the generator are fabricated in two halves and are welded together for a total weight of more than 400 tonnes.

Snowy Hydro has an integral part to play in establishing high standards of equipment manufacturing, which meet the engineering requirements for our critical Snowy 2.0 project infrastructure.

News

BREAKTHROUGH MILESTONE FOR SNOWY 2.0

05/01/2024

Snowy Hydro is pleased to announce another major achievement for the Snowy 2.0 pumped-hydro project, with the breakthrough of the final three metres of the power station’s 223-metre long transformer hall cavern crown.

The Snowy 2.0 delivery team began excavating the transformer hall and machine hall caverns in June 2023. The Snowy 2.0 power station will be located approximately 800m underground at Lobs Hole in the Snowy Mountains. When completed, the machine hall will be 251 metres long and 52 metres high and the transformer hall 223 metres long and 46 metres high. Together they will form one of the largest and deepest caverns in the world, big enough to fit the Sydney Opera House inside.

Precise 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. The excavation sequence of the cavern crowns is carefully planned and executed, as the rock mass relaxes and moves inwards as the excavated void increases. These movements are expected and are closely monitored during the process.

So far, about 17,000 cubic metres of material has been excavated from the central heading of the transformer hall cavern crown. The heading has been advanced in 3-4 metre rounds from either end of the cavern for a total of 77 blasts.

The machine hall cavern crown breakthrough will take place in coming weeks, and widening of both cavern crowns, known as side slashing, is ongoing and planned for completion in coming months. Excavation of both power station caverns is set to continue through 2024.

The breakthrough of the transformer hall cavern crown represents another important milestone for the Snowy 2.0 pumped-hydro project that will significantly expand the existing Snowy Scheme and will provide an added 2,200 megawatts of on-demand power and 160 hours of large-scale renewable energy storage for the National Electricity Market.

Snowy Hydro CEO Dennis Barnes said: “The breakthrough of the transformer hall cavern crown is a really pleasing milestone for the Snowy 2.0 team, reinforcing that we’re making good progress with our underground drill and blast excavation activities. We are well on our way to delivering the largest single project that will help ensure Australia’s secure and reliable transition to renewable energy.”

News

SNOWY 2.0 PROJECT UPDATE – DECEMBER 2023

19/12/2023

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.

News

SNOWY 2.0 TUNNELLING RESTARTS AT TANTANGARA

13/12/2023

Tunnelling of the Snowy 2.0 headrace adit at Tantangara has restarted following NSW government approval for the project’s planning modification.

Tunnel boring machine (TBM) Florence’s initial advance commenced last week. Tunnelling is being conducted in closed (slurry) mode and progress is slow and steady. The project has engaged specialist experienced personnel to manage this process.

Snowy Hydro CEO Dennis Barnes welcomed the milestone, which comes after a delay caused by soft ground conditions and the emergence of a sinkhole above TBM Florence.

“We were very pleased to receive the green light for tunnelling at Tantangara to recommence and to allow remediation of the subsidence area,” Mr Barnes said.

“The conditions of approval were developed through the extensive review, public consultation and determination process, and will be strictly adhered to as we get back underway with excavation of the tunnel.

“The Snowy 2.0 delivery team is acutely aware of its responsibilities working in the sensitive environment of Kosciuszko National Park. We are focused on achieving excellent environmental outcomes throughout construction of this pumped-hydro expansion of the Snowy Scheme and critical infrastructure for Australia’s transition to renewable energy.”

The modification approval extends the project’s western boundary above the TBM at Tantangara. This will enable close monitoring of surface conditions as TBM Florence advances. Surface monitoring will continue until there is at least 100 metres of overburden (distance from the TBM to the surface).

In preparation for the restart of tunnelling at Tantangara, extensive geotechnical investigations were carried out on the headrace adit alignment, along with ground improvement works.

Elsewhere on the project:

At Talbingo, the Snowy 2.0 project continues to make good progress with excavation of the tailrace tunnel. TBM Lady Eileen Hudson has excavated approximately 1,000 metres since its relaunch in July.
Manufacturing of Snowy 2.0’s six pumped-hydro units that will generate up to 2,200 megawatts of power for Australia’s electricity grid is in full swing.
Five of the six 153 tonne spiral cases have been manufactured, along with four draft tube liners and cones, three main inlet valves and other major power station components, including the first turbine runner. One of the 13 metre long, 7.5 metre wide spiral cases was recently delivered to Lobs Hole, making a 442-km night time journey from Port Kembla to the Snowy Mountains.

Snowy 2.0 spiral cases and other components at the Voith Hydro Shanghai factory.

News

SNOWY 2.0 PROJECT UPDATE – NOVEMBER 2023

05/12/2023

Snowy 2.0 is entering an exciting phase as we build the largest single project that will help ensure Australia’s secure and reliable transition to renewable energy.

In this month’s project update Hamish Pryor, construction director for Snowy 2.0, provides an overview of the power station equipment manufacturing that is in full swing.

The bespoke Snowy 2.0 power station components are being fabricated with precision and skill at one of Voith Hydro’s global production facilities in Shanghai, China.

Voith Hydro is partnering with Snowy 2.0 to make the six pumped hydro units that will generate up to 2,200 megawatts of power for Australia’s electricity grid.

Voith has more than 150 years of experience in hydropower systems and its highly skilled team is developing efficient and reliable equipment that will support the 150-year design life of Snowy 2.0.

At the Shanghai factory, every item that is manufactured for the project undergoes comprehensive quality checks and testing before being shipped to Australia.

Voith’s quality, research and development team in Germany works directly with its Shanghai engineering experts on design, manufacturing processes and quality control. The team also collaborates closely with the Snowy 2.0 project team in Australia.

Among the large components being manufactured are the 13 metre-wide spiral cases and the main inlet valves – each weighing 140 tonnes and 2.2 metres in diameter – and the 31-tonne runners.

The runner is the heart of a hydro power turbine – it’s the rotating element that drives the generator to produce electrical energy. Exceptional machining and highly specialised welding skills are used to fabricate the components.

In Voith’s state-of-the-art electrical workshop more than 2,700 stator bars – which will be connected to the transformers to deliver power produced in the generators – are being manufactured.

Snowy Hydro has team members based in Shanghai to conduct quality assurance activities and monitor progress, while specialist mechanical and electrical engineers attend factory acceptance testing.

Recently, the final acceptance test for the first unit runner was completed and celebrated with a photo in the workshop.

In the Snowy Mountains in NSW, the Snowy 2.0 delivery team is also creating water intakes at the Talbingo and Tantangara reservoirs. A 28-metre diameter, 250 metre-deep surge shaft is being built at Marica and will become one of the largest operating shafts in the world.

Tunnel boring machines excavating the Snowy 2.0 tunnels are lining them with locally-made concrete segments – we’ve manufactured almost 90,000 of them at the Cooma precast factory so far. And the underground power station cavern complex is underway, with drill and blast excavation.

News

SNOWY 2.0 PROJECT UPDATE – OCTOBER 2023

08/11/2023

In this month’s project update, we check on tunnel excavation at Talbingo, progress at the upstream surge shaft at Marica, and we hear about the specialised drilling underway to prepare for services such as power and communications between Lobs Hole, Marica and Tantangara.

Will Binsted, Snowy 2.0 Lobs Hole Construction Manager, has been working on the project for four years and is responsible for coordinating both surface and underground works. Will, who lives locally in Tumut, liaises with technical specialists as well as designers and project engineers across the busy worksite.

To see the latest Snowy 2.0 project’s statistics, view the fact sheet here.

A complex task is underway at Lobs Hole to drill boreholes for the pipes that will house power, water and fibre optic cable for communications across three of the Snowy 2.0 sites.

Horizontal directional drilling (HDD) is being used to drill 2.2km-long boreholes from Lobs Hole to Marica. The holes are initially 300 millimetres in diameter and have an elevation difference of 650 metres.

Two drilling operations are underway from top and bottom and will join up to create a continuous borehole before being enlarged to 660 millimetres in diameter.

This type of drilling is used for service lines that cross under waterways or underground structures and requires a high level of skill to maintain directional control while operating a drill string up to 1.8km long. Snowy 2.0 has contracted HDD experts Michels for the project.

The boreholes eliminate the need to construct approximately five kilometres of roads and excavate up to 60 metre cuts in the steep terrain, helping the Snowy 2.0 project team minimise environmental impacts.

HDD techniques will also be used to take services under the Snowy Mountains Highway and waterways across the plateau through to the Tantangara worksite.

At Marica, the 28 metre diameter headrace surge shaft is now one-fifth of the way to its final depth of 263 metres and we’re starting drill and blast activities. There are two hoisting buckets called kibbles with a capacity of 25 tonnes for loading out excavated rock.

Excavators break up the rock with hydraulic hammers before it’s loaded into the kibbles and craned out of the shaft. The kibbles are lowered into hoppers and the rock drops into an articulated dump truck before being removed to a temporary stockpile area.

With the shaft now more than 50 metres deep, an integrated work platform and personnel hoist is being installed to provide worker access. We’ve installed ventilation ducts to manage air quality.

At Talbingo, tunnelling of the tailrace adit is complete. TBM Lady Eileen Hudson is now excavating the tailrace tunnel alignment and heading towards the power station complex. This marks the start of the first power waterway on the Snowy 2.0 project.

Excavation is ahead of schedule, with more than 26 metres recently excavated in a single day. The tailrace tunnel is six kilometres in length, with TBM excavation continuing through to mid-2025.

Snowy 2.0 is being engineered to deliver clean and reliable energy storage and generation for the next 150 years. The target date for commercial operation of all units is December 2028, with first power expected in the second half of 2027.

News

SNOWY 2.0 PROJECT UPDATE – SEPTEMBER 2023

05/10/2023

Following the recent announcement of the Snowy 2.0 project reset, the Snowy Hydro and Future Generation contractor teams are now a single team, working in close collaboration to achieve full commercial operation by December 2028.

The Snowy 2.0 Project Team is focused on excellent environmental outcomes while maintaining all-important safety principles. Safety is the number one priority for Snowy Hydro and core to the company’s values. High expectations for the management of all safety risks extend across the Snowy 2.0 project, without compromise.

Snowy 2.0 is critical to Australia’s transition to a low-carbon economy and when complete it will have broad-scale environmental benefits. Consistent with its responsible operation of the Snowy Scheme in Kosciuszko National Park for almost 70 years, Snowy Hydro is equally committed to minimising potential impacts from Snowy 2.0.

SAFETY PERFORMANCE

– As at September 2023, the project’s 12-month rolling TRIFR (Total Reportable Injury Frequency Rate) is 2.97, below the target of 4.0.**
– There has been a reduction in recordable and serious incidents on the project, with a focus on planning and a coordinated approach to safety management.
– Snowy 2.0 works closely with Comcare and SafeWork NSW and will continue to incorporate lessons learned and findings from the regulator into operational practices.
**Calculated per million hours worked. Total hours worked to end September 2023: >17.7 million.

Construction of Snowy 2.0 will temporarily impact less than 0.1% of the park with any short-term unavoidable impacts rehabilitated throughout the project, in accordance with environmental project approvals. This includes around $100 million provided by Snowy Hydro to the offsets program for Kosciuszko National Park. Once operational, Snowy 2.0’s footprint within the park will be only 0.01%.

ENVIRONMENTAL PERFORMANCE

– 4 independent audits of the Snowy 2.0 project undertaken since project commencement.
– 1,500 hours spent annually to proactively monitor the 163 biodiversity sites.
– More than 200 kilograms of native seed collected over three years for rehabilitation activities.
– 27 heritage site excavations and more than 35,00 indigenous artefacts salvaged and currently being documented, adding to the history of the Snowy Mountains Indigenous people.

In this month’s update from the main worksite at Lobs Hole, Project Integration Manager Paul Smith recaps progress to date with over 40 per cent of Snowy 2.0 now complete, including:

Excavation of the 2.85 kilometre main access tunnel, lined with almost 13,000 locally manufactured concrete segments.
Excavation of the 2.9 kilometre emergency, cable and ventilation tunnel.
Major upgrade of Ravine Road, the steep and winding 15 kilometre access road into Lobs Hole.
Infrastructure to support construction including the main yard workshops, worker campsites and more than 50 kilometres of access roads across three main worksites at Lobs Hole, Marica and Tantangara.

Excavation is underway of the huge 250 metre-long underground power station cavern and the tailrace tunnel, and TBM Kirsten is being modified to excavate the world-leading inclined pressure shaft. Drill and blast to create 11 cross passages and construction tunnels continues.

Above ground, there is plenty of activity across all sites. Lobs Hole Surface Works Project Manager Steve Lee helps ensure the Snowy 2.0 project is delivered in a safe and timely way, and to the quality standards and requirements of Snowy Hydro.

Surface works refers to a broad mix of activity such as haulage of spoil, maintenance of site roads, environmental controls, main yard area activity, office facilities and directional drilling, as well as the Talbingo intake build.

Latest progress on site includes Stage 2 earthworks with a recent blast covering an area of 4,500 square metres. About 10,000 cubic metres of material is being removed as the excavation of the 104-metre-high intake continues.

Snowy 2.0 is the largest renewable energy project under construction in Australia and will provide crucial deep storage central to Australia’s renewable transition. When complete, Snowy 2.0 will deliver 2,200 megawatts of dispatchable generation.

News

SECURING THE FUTURE OF CRITICAL ENERGY TRANSFORMATION PROJECTS

31/08/2023

Snowy Hydro today announced the outcomes of its major projects resets, for Snowy 2.0 and the Hunter Power Project.

Snowy 2.0

Revised total cost to complete is $12 billion. At the end of June 2023, expenditure on the project was $4.3 billion, with 80% of these funds reinvested in the Australian economy.
First power to be delivered in the second half of 2027 and a target date for commercial operation of all units of December 2028.
The fixed-price EPC Contract was executed by Snowy Hydro and Future Generation Joint Venture (FGJV) following Final Investment Decision in a relatively benign and supportive environment. The EPC Contract is no longer fit for purpose.
Snowy Hydro and FGJV are finalising an amendment to the existing EPC Contract to move to an incentivised target cost contract model. Snowy Hydro will also settle all outstanding claims with FGJV.
Delivery of an additional 200 MW or 10% capacity; bringing total capacity to 2,200 MW.
Snowy 2.0 is the largest renewable energy project under construction in Australia and will provide crucial deep storage central to Australia’s renewable transition.
The value of Snowy 2.0 to the national electricity market has increased materially since the Final Investment Decision in December 2018.
Snowy 2.0 will provide 350,000 MWh of energy storage for 150 years.
Snowy 2.0 remains value accretive, with the Company currently projecting a NPV of approximately $3 billion (based on a $12 billion revised target total cost and December 2028 delivery).
Snowy Hydro is working closely with its Shareholder to develop an appropriate capital structure for the Company to support the increase in costs and to maintain the Company’s target credit rating of BBB+.

HPP

The total target cost is now $950 million and will be funded by Snowy Hydro.
The project delivery remains December 2024.
The project remains economically viable on a forward looking basis with the value of its firming capacity clearly demonstrated in the May/June 2022 energy crisis.

Snowy Hydro CEO Dennis Barnes said the project resets will enable the commercially sustainable and successful delivery of both projects.

“I am committed to ensuring these critically important projects are transparent and are placed on a robust and sustainable footing. Moving to an incentivised target model with FGJV will result in closer collaboration, stronger oversight and alignment of interests between Snowy Hydro and FGJV. ” Mr Barnes said.

“Snowy 2.0 is being engineered to deliver clean and reliable storage and electricity generation for Australians for the next 150 years. It is a truly transformative national project that is generating jobs and significant investment in regional areas; it will deliver benefits immediately following its completion and will continue to do so for many future generations of Australians.

“Snowy 2.0 involves billions of dollars of investment, with approximately 80% going into Australian jobs, goods, services and skills. We are building the skills of local workers that can later be used elsewhere to assist in Australia’s ongoing energy transition.”

“The Hunter Power Project is an important project in Australia’s energy transition, enabling the roll-out of wind and solar projects by firming these intermittent generation sources into reliable power,” Mr Barnes concluded.

Fact sheet

Webuild Clough media statement

Background Information

Snowy Hydro today detailed the outcome of the review and reset process for key electricity projects, Snowy 2.0 and the Hunter Power Project.

Snowy 2.0

The estimated total cost for Snowy 2.0 project delivery has been revised to $12 billion, with expenditure on the project to date of $4.3 billion. The terms of the contract with Future Generation Joint Venture (FGJV) are being finalised to move to an Incentivised Target Cost contract model, which will result in closer collaboration, stronger oversight and alignment of interests between Snowy Hydro and FGJV. Snowy will also settle all outstanding claims with FGJV.

The target date for commercial operation of all units is December 2028 with first power to be delivered in the second half of 2027.

Through the project reset process Snowy Hydro has worked with FGJV and hydro technology contractor Voith Hydro to increase the capacity of the power station by 10%. Snowy 2.0 will now deliver dispatchable generation capacity of 2,200 MW, as well as providing energy storage of 350,000 MWh (or 160 hours of generation at maximum output).

The cost revision reflects the compound effect of extraordinary factors. The external factors have impacted major projects around Australia and globally, in particular:

The major disruption caused by the Covid-19 pandemic;
Delayed ability to mobilise, given critical shortages of skilled labour, exacerbated by quarantine and movement restrictions;
Extended and ongoing disruption to global shipping and supply chains caused by the pandemic, conflict and natural disasters, delaying access to key materials;
Significant inflation in costs of key construction materials and inputs; and
Significant inflation in labour costs.

In addition to the external factors, the project has been impacted by:

Design immaturity at final investment decision, with a number of design elements requiring more time to complete due to their technically complex nature. The final design now being more expensive to construct; and
The impact of variable site and geological conditions, with the most impactful being the soft ground encountered that is delaying tunnel boring machine (TBM) Florence’s progress at Tantangara.

Despite the challenges outlined above, the project remains economic. Strong and growing market demand for dispatchable electricity is expected to underpin demand for the services provided by the project well into the future.

Construction of Snowy 2.0 is now approximately 40% complete and solid progress continues to be made, including:

Excavation of the main access and emergency cable and ventilation tunnels is now complete – approximately 6km of tunnelling;
Excavation on the 6km tailrace tunnel has commenced and tunnelling on the 1.45km inclined pressure shaft will commence shortly;
Work on the underground power station is now underway with access available from both ends and excavation and support of cavern crowns underway;
Excavation at the Talbingo intake (where water will enter during pumping and exit during generation) is halfway complete, with 310,000m³ of earth excavated, while the first stage of earthworks at the Tantangara intake are complete, involving the movement of 205,000m³ of earth; and
Manufacturing of the six pump turbines has commenced, the first major mechanical component has been shipped and has been transported to site.

Meanwhile, excavation of the headrace tunnel by TBM Florence is now ready to be continued, subject to the receipt of necessary regulatory approvals.

The project currently has a team of approximately 2,700 Australians dedicated to its safe and efficient delivery. An additional 1,500 jobs are forecast over the project’s lifespan.

Hunter Power Project

The Hunter Power Project has experienced similar challenges to Snowy 2.0 and following a comprehensive review the expected cost is now $950 million. Despite the increased cost the Hunter Power Project remains economic.

Construction continues to progress on schedule, with about 460 people working on the project, which remains on track to be delivered by December 2024.

News

SNOWY 2.0 PROJECT UPDATE – JULY 2023

28/07/2023

July marked an exciting milestone for Snowy Hydro, the Snowy 2.0 project and for one of its three tunnel boring machines. Tunnel boring machine (TBM) Lady Eileen Hudson was the first machine to start tunnelling on the pumped-hydro mega project, the first to complete a tunnel and is now underway on her second tunnel excavation.

Snowy 2.0 senior project manager, Rodd Brinkman, is onsite at the Talbingo adit, where teams have been preparing to relaunch TBM Lady Eileen into the mountain.

The TBM will excavate the 6km tailrace tunnel to connect Talbingo Reservoir to the underground power station complex. Water used to generate 2,000 megawatts of power from Snowy 2.0 will flow out of the tailrace tunnel. Water also enters this tunnel when the power station is pumping.

After completing the 2.8km main access tunnel (MAT) in 2022, it has been a big task to disassemble and safely extract TBM Lady Eileen and reassemble her with new components before commissioning. The conveyor stacker, grout batch plant, and chiller plant were also relocated from the MAT portal to the Talbingo adit.

Before a TBM begins her journey underground, it is traditional for the machine and crew to be blessed for a safe journey under the watch of St Barbara, the patron saint of tunnelling and underground work. The tradition of blessing is acknowledged at tunnelling sites all over the world.

Local parish priest Father Mark Croker blessed the TBM at an onsite ceremony with many Snowy 2.0 workers in attendance. The machine was then switched on and began cutting the rock face. This is the fourth TBM launch for Snowy 2.0 and a major achievement for the Snowy Scheme expansion project.

TBM Construction Manager Derek Whelan manages all Snowy 2.0 tunnelling activities, as well as the TBM construction personnel. He was on-hand to run through Lady Eileen’s impressive components, including a new 378-tonne cutterhead.

The cutterhead is made up of 70 cutting discs each weighing 290 kilos that will excavate the varying geology of the 11-metre diameter tunnel. At 137 metres in length and weighing 2,300 tonnes, the TBM is a moving factory with many parts working together in a complex operation.

More than 27,000 concrete segments manufactured at the Polo Flat, Cooma, precast facility will be used to line the tailrace tunnel with the segment erector, segment feeder, segment cranes, and sophisticated grouting system all onboard the TBM.

The TBM is also equipped with a guidance system that provides data to the machine’s pilot, to the nearest millimetre. This information is mirrored above ground and monitored by Snowy 2.0’s construction and engineering teams.

Snowy 2.0: Underpinning Australia’s transition to a renewable energy future

News

SNOWY 2.0 TANTANGARA TUNNELLING UPDATE

28/07/2023

Successful ground stabilisation works and construction of a slurry treatment plant at Tantangara have been carried out by Snowy 2.0 teams prior to tunnel boring machine (TBM) Florence being able to restart excavation of the headrace tunnel.

Final commissioning tests are underway for the onsite slurry plant that means the dual-mode machine can switch from open excavation to a closed, pressurised mode. This method of excavation will enable stable excavation and efficient progress through softer ground conditions when required.

A significant testing regime has confirmed grouting and stabilisation of the loose material around TBM Florence has been effective.

Additional stabilisation continues from the surface to solidify loose material above the machine and directly in front of the TBM cutterhead and the rock mass the machine is just short of.

We’re carrying out rotations of the cutterhead and minor advances of TBM Florence to ensure the machine is correctly positioned for final commissioning and to confirm the ground support activities are working.

Additionally we are working with NSW departments on environmental approvals for remediation of the surface depression above TBM Florence and to provide assurance that this will not reoccur.

The plan is likely to go on public display in the coming weeks.

The slurry treatment plant will process and separate materials used when the TBM is in closed excavation mode, including bentonite (an absorbent, swelling clay), which is placed into a tank and reused.

News

SNOWY 2.0 PROJECT UPDATE – JUNE 2023

26/06/2023

In the June update of the pumped-hydro expansion of the mighty Snowy Scheme, Snowy 2.0’s Alex Woschitzka explains construction progress at the massive Talbingo and Tantangara intakes. The project’s Quality Coordinator also checks in on the transformation of a narrow fire trail through steep terrain into a road suitable for heavy vehicles.

Significant progress has been made at the Talbingo intake, where water will exit the tailrace tunnel when Snowy 2.0 generates power. This is also where water enters the tunnel for pumping.

Construction teams have moved more than 310,000 cubic metres of earth to date, about half the total amount that will need to be moved. More than 24,000 metres of rock bolts have been installed and 8,300 square metres of shotcrete sprayed to support the wall.

As part of quality assurance, the shotcrete must be tested for compressive strength. Samples are taken from the truck and also cored from the face to ensure it meets the intended strength requirements. For the rock bolts, pull-testing is conducted to ensure they have been correctly installed, and meet the design and quality requirements.

When completed, the total height of the Talbino intake excavation will be 104 metres, with about 31 metres of that below the water level. The concrete intake structure will be an impressive 50 metres in height.

Construction is well underway on an internal access road through mountainous terrain. With the help of Snowy 2.0 subcontractor Leed, a narrow fire trail will be widened into a six-kilometre road to enable heavy vehicles to access a rock emplacement area on Talbingo Reservoir.

Works began from both ends across very challenging terrain, achieving a major milestone recently when the two pioneering fronts joined across the Middle Creek cliffs. A temporary bridge with a 36-metre span has been installed across Middle Creek and is capable of supporting a fully-loaded 80-tonne dump truck.

In another milestone achieved in June, stage one earthworks have now been completed at the Tantangara intake. The first stage involved excavation of about 205,000 cubic metres of earth with a further 78,000 cubic metres of drilling and blasting earthworks expected in the next stage.

To support the excavation, more than 18,000 metres of rock bolts have been drilled and installed, and approximately 6,100 square metres of shotcrete sprayed. The excavation is currently about 26 metres deep and will be extended to a total depth of 55 metres.

Tantangara intake is where water will enter the headrace tunnel when the Snowy 2.0 power station is in generation mode. When in pumping mode, water will exit through the intake and fill Tantangara Reservoir.

News

SNOWY 2.0 PROJECT UPDATE – MAY 2023

30/05/2023

May was a milestone month for the Snowy 2.0 team with the completion of the emergency, cable and ventilation tunnel, or ECVT – another vital step in the construction of Snowy Hydro’s new pumped-hydro expansion megaproject.

Snowy 2.0 senior project manager Rodd Brinkmann explains the next stage of the project from his base at Lobs Hole, as preparation for excavation for the underground power station cavern gets underway.

The ECVT is a 2.93 kilometre tunnel that runs adjacent to the main access tunnel and provides alternate access to the site of the underground power station. Tunnel boring machine (TBM) Kirsten recently completed excavation of the ECVT and will soon start tunnelling the inclined pressure shaft. This very steep shaft links to the headrace tunnel from Tantangara Reservoir.

TBM Kirsten will need to undergo modifications to excavate the 25-degree incline, including installation of a screw conveyor to extract excavated rock from the cutterhead to a sandwich conveyor system. With such a steep incline, construction of the 1.45km shaft with its concrete segment-lined tunnel, will be a world first.

In the main access tunnel, or MAT, construction of cross passages and construction access tunnels is well underway with 850 metres of drill and blast tunnel excavation completed. Of the five cross passages linking the MAT and the ECVT, two are fully excavated and waiting on breakthrough into the ECVT. Key construction tunnels are also being excavated to provide access to the machine hall, transformer hall and the top of the tailrace surge shaft.

Workers have reached the main cavern areas from both ends and will soon commence excavation and support of the cavern crowns or ceilings of the power station halls. The excavation sequence of the cavern crowns is critical, as the in situ rock mass will relax and move inwards as the excavated void increases. These movements will be closely monitored during the process. Geotechnical drilling and plate load tests will measure and confirm the characteristics of the rock geology around the power station.

Dynamic 3D models of the power station caverns are also being used. 3D models are created using digital engineering to transform 2D design drawings and are displayed in the state-of-the-art immersive theatre at Snowy Hydro’s Discovery Centre in Cooma, where Snowy 2.0 engineers can collaborate with power station design experts from around the world. Once construction is complete, the detailed 3D models will be a valuable tool for asset maintenance.

With so much activity in the tunnels, the current Snowy 2.0 underground workforce will increase by another 200 people in the coming months.