SNOWY 2.0 PROJECT – COMMUNITY INFORMATION SESSIONS IN NOVEMBER
02/11/2023
Interested in the latest updates from the Snowy 2.0 renewable energy mega project?
Snowy Hydro and Snowy 2.0 principal contractor Future Generation Joint Venture are inviting local community members to attend information sessions being held throughout the Snowy Mountains in November.
These in-person events enable locals to be updated about the project, ask questions and provide feedback. Hear from the Snowy 2.0 team about:
the recent project reset
project progress, construction activities and news
traffic management, environment and safety
accommodation, recreation access and other local issues;
local suppliers, jobs and training on Snowy 2.0.
Snowy Hydro CEO Dennis Barnes said with a significant public focus on Snowy 2.0 in recent months, the sessions provided opportunities to find out more directly from project team members.
“We are committed to being open and transparent with you – our local communities – about our large and complex pumped-hydro project. A project of this scale and complexity has, and will, face challenges, but we continue to make solid progress across our construction and manufacturing operations.
“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 project that is generating jobs and significant investment in regional areas.
“I encourage everyone to come along to one of our community information sessions to hear the latest about Snowy 2.0, discuss any local concerns that you may have and ask questions.”
The Snowy 2.0 community information sessions in November will be held in Talbingo, Tumut, Tumbarumba, Cooma and Adaminaby.
There will be some drop-in sessions, with the chance to speak one-on-one with project team members, and events featuring a formal presentation followed by community Q&As.
Community information sessions schedule:
Date
Town and location
Time
Wednesday 8 November 2023 Wednesday 8 November 2023
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.
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.
TagEnergy and Snowy Hydro ink momentous renewable Power Purchase Agreement
21/08/2023
Snowy Hydro to purchase 40 percent of Golden Plains Wind Farm energy and green certificates
Global clean energy enterprise TagEnergy has signed a significant renewable Power Purchase Agreement (PPA), entering a deal that will see Snowy Hydro take 40 per cent of the energy and green certificates (LGCs) generated by the 756MW first stage of Golden Plains Wind Farm.
This transaction is the first PPA for the Golden Plains Wind Farm since the first stage of the 1,300MW mega project near Geelong, Victoria achieved financial close in November 2022 on a merchant basis, which was unique at the time.
It comes as TagEnergy negotiates further PPAs for the project that has generated significant interest for its quality and location.
Franck Woitiez, Chief Executive Officer, TagEnergy said achieving financial close of Golden Plains Wind Farm East without the need for PPAs proved the effectiveness of its innovative investment approach.
“Now, this landmark PPA with Snowy Hydro proves our strategy to progressively contract the energy production during construction and operation. It also reflects the confidence major industry players like Snowy Hydro have in our large-scale renewables project expertise,” Mr Woitiez said.
“We are proud to enter this agreement with Snowy Hydro as we both work to ensure energy security and accelerate the transition to renewable energy as part of a rapidly growing industry,” he said.
The transaction has helped enable Snowy Hydro to secure a significant portion of its energy and LGC needs with a quality project that is at an advanced stage.
Snowy Hydro Chief Executive Officer, Dennis Barnes, said “our partnership with TagEnergy is a significant step in supporting the decarbonisation of the National Electricity Market and further enabling Australia’s transition to renewables.”
Snowy Hydro Chief Commercial Officer, Gordon Wymer, added, “TagEnergy has succeeded in developing an investment structure that provided optimal outcomes for all stakeholders. This has enabled Snowy to continue to expand its ability to provide clean, green, cost-effective renewable energy to our customers, and paves the way for further cooperation with TagEnergy on other developments.”
Construction on the $2bn, 756MW stage one development featuring 122 turbines officially began in April 2023 following months of early works including road upgrades. It is expected to start producing renewable energy in the first quarter of 2025.
The estimated annual emissions abatement is an average 770,000 tonnes CO 2 -e, or more than 23 million tonnes CO 2 -e over the project’s 30-year lifetime.
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
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 madeat 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.
The second of two generator stators that will power Snowy Hydro’s Hunter Power Project has arrived onsite at Kurri Kurri after its journey from the Port of Newcastle late last night.
The 150-metre-long convoy containing the 314-tonne generator stator left the Port of Newcastle at 9pm on Saturday evening and arrived at the Kurri Kurri site at 2am on Sunday, where it was unloaded and positioned for installation.
The convoy included six prime movers, four police escort vehicles and four pilot vehicles.
The first generator was transported two weeks ago and travelled the same route to Kurri Kurri from the Mayfield berth, via Industrial Drive, Maitland Road, Newcastle Inner City Bypass and the Hunter Expressway.
The two generator stators were prepared for transportation at the port over a period of two days after arriving from Japan late last year and earlier this year. When installed, the generators will spin from the power of the two open cycle gas turbines (OCGTs), which in turn will generate the 660 megawatts of electricity the Hunter Power Project is delivering for the National Electricity Market.
Snowy Hydro CEO Dennis Barnes said this project milestone was the result of months of meticulous planning from the Hunter Power Project team.
“Moving these two large components of the power station to our construction site required many months of work and liaison with the Port of Newcastle, the team at Mitsubishi in Japan, and local engineered transportation company Rex Andrews.
“Investment in dispatchable generators like the Hunter Power Project is vitally important as Australia transitions to renewable energy, which will ultimately benefit the environment and future generations,” Mr Barnes said.
The Hunter Power Project is expected to be operational by 2024.
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.
The Snowy 2.0 pumped-hydro mega project has achieved another important construction milestone, with a second tunnel excavation completed at Lobs Hole in the Snowy Mountains.
The 2.93-kilometre emergency, cable and ventilation tunnel (ECVT) has been excavated and fully lined with 13,140 locally-manufactured concrete segments by tunnel boring machine (TBM) Kirsten. This achievement follows the excavation of the adjacent main access tunnel (MAT), which was completed in October 2022.
Snowy Hydro CEO Dennis Barnes said Snowy 2.0 was continuing to make solid progress, with around six kilometres of tunnelling by TBMs completed and drill and blast excavation of the power station cavern about to start.
“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.
“We are also using drill and blast methods to construct cross passages linking the ECVT with the MAT.
“Meanwhile TBM Kirsten, which is setting a global standard in TBM technology, is being modified to carry out another very specific task – to excavate the inclined pressure shaft and line it with specially-designed and locally manufactured concrete segments.
“The shaft is 1.45km long and excavating a segment lined tunnel of this length at a very steep 47% incline using an 11-metre diameter TBM is without precedent internationally.”
Modifications to Kirsten 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.
Also being installed is a screw conveyor to extract excavated rock from the cutterhead to a sandwich conveyor system with face-to-face rubber belts that help constrain the crushed rock so that it can be transported down the steep slope without spillage.
Additional plant and equipment will also be installed in the ECVT tunnel to support the excavation activities including; an overhead crane, a conveyor transfer station, monorail manrider for personnel access and rack and pinion mechanism for plant access to the TBM,
There is currently a project workforce of more than 2,700 across four major worksites building Snowy 2.0, a critically important, pumped-hydro expansion of the Snowy Scheme that will help underpin Australia’s transition to renewables.
ECVT fast facts
2.93-kilometres in length
10 metres internal diameter
Lined with 1,460 concrete rings with 9 segments per ring installed by TBM Kirsten
Precast segments are manufactured locally in Cooma
ECVT has five cross-passages linking it to the adjacent main access tunnel
Provides secondary access with clean air to the power station complex and will be used permanently for ventilation and high voltage cables, and intermittently for general access and maintenance.
In our April update of the Snowy 2.0 pumped-hydro project, Snowy Hydro CEO Dennis Barnes pays tribute to Alan Machon, who tragically died in a road accident. Alan was a member of the Future Generation team working to deliver Snowy 2.0.
Out onsite, Snowy 2.0 Integration Manager, Paul Smith, joins us from the recently completed Ravine Road, we meet the captain of the Lobs Hole Emergency Response Team and we stop by the Talbingo adit to check on progress of TBM Lady Eileen Hudson’s reassembly in readiness for her second major tunnelling task.
The construction of Ravine Road was one of the first projects undertaken for Snowy 2.0. Originally little more than a dirt track, the main access into the Lobs Hole site has been transformed to provide safe all-weather access for project trucks and light vehicles.
The steep, winding 15-kilometre road is now two lanes wide and in March 2023 it was fully sealed with line marking, snow poles and reflective markers installed to help guide road users in low visibility conditions. With an 850-metre elevation difference from top to bottom, the upper section of Ravine Road is above the snow line.
Areas disturbed during construction are being reinstated and the rehabilitation process is underway. When the Snowy 2.0 project is complete, the general public will be able to use Ravine Road to access a popular camping area once restricted to 4WD vehicles.
At the Talbingo adit, tunnel boring machine Lady Eileen Hudson is being reassembled in preparation for excavation of the tailrace tunnel. New components including the cutterhead and tailskin will soon be lifted into the TBM cradle to be attached to the shields and main drive. After completing the excavation of the main access tunnel, the TBM gantries were removed using self-propelled mobile transporters and will be attached to the machine so it can begin excavating the six-kilometre tunnel. The vertical conveyor belt stacker has been assembled, construction of the water treatment plant is progressing and the grout plant will soon be commissioned.
Snowy 2.0 emergency response teams, or ERTs, regularly conduct training to keep the onsite workforce safe and to prepare for possible emergencies such as vehicle rescues and bushfires.
Future Generation’s Lobs Hole ERT captain, Drew Butters, is a Snowy Mountains local who has worked on the project for three years. He has had a life-long association with emergency response and fire fighting in the Rural Fire Service and is currently the Adaminaby RFS captain.
ERTs are trained to deal with bushfires, general firefighting, emergency response and rescue. Emergency Response Teams have a small crew with experienced full-time members, plus a number of volunteers at each work site.
Snowy Hydro’s management team is working towards resetting the delivery timeline and budget for the Snowy 2.0 project with its principal contractor, Future Generation Joint Venture (FGJV), as part of an ongoing project review.
The reset will ensure this critically important clean energy infrastructure project is placed on a robust and sustainable footing for FGJV to progress the schedule in a realistic and productive manner.
While significant progress has been achieved by FGJV on Snowy 2.0, there are delays to Snowy 2.0’s contracted schedule and likely cost impacts beyond the contingency allowed, which remain under review by Snowy Hydro.
There are four broad categories of factors contributing to schedule delays and likely cost increases:
the mobilisation and resourcing implications of the COVID-19 pandemic;
the effect of global supply chain disruption and inflation impacting the cost and availability of a skilled workforce, materials, and shipping;
a number of design elements requiring more time to complete due to their technically complex nature, with 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.
Snowy Hydro anticipates that the timeline for full commercial operation is delayed by a further 12-24 months from the current publicly released dates:
Milestone
Earliest
Latest
First Power
June 2027 – December 2027
June 2028 – December 2028
Commercial operation of all units
December 2028
December 2029
Snowy Hydro expects more detail on the budget implications of the project reset around July 2023, and this will be clearly communicated with key project stakeholders.
Snowy Hydro CEO Dennis Barnes said:
“Since joining Snowy Hydro earlier this year I have focused on ensuring our major projects are placed on a realistic and sustainable footing, while maintaining construction progress.
“This project is critically important to the transition of Australia’s electricity grid and it’s crucial that we are working to a safe, efficient and realistically achievable timeframe to enable orderly planning for all our stakeholders. I am committed to being transparent about our progress and how we are proactively managing the inevitable issues and challenges that arise in a complex project like this.
“While many other major infrastructure projects have been impacted by the same challenges, Snowy 2.0 continues to make positive progress.
“Snowy 2.0 is providing significant employment and economic benefits both regionally and domestically. There are currently over 2,400 people employed on the project and thousands more jobs generated indirectly through supply chains and support services.
“TBM Kirsten has tunnelled 2.9 km to reach the underground power station cavern complex and we now have access to this site from both ends. We shortly expect to commence the 6km tailrace tunnel that will feed into Talbingo Reservoir and the excavation of intakes at Talbingo and Tantangara are proceeding very well.”
Snowy 2.0 is a critically important, pumped-hydro expansion of the Snowy Scheme that will help underpin Australia’s transition to a renewable energy future.
Construction of Snowy 2.0 continues to make progress across multiple worksites. At Lobs Hole, tunnel boring machine (TBM) Lady Eileen Hudson has completed excavation of the 2.7km main access tunnel and TBM Kirsten is almost finished excavating the adjacent 2.9km emergency, cable and ventilation tunnel (ECVT).
At Tantangara, the project team is currently conducting works to stabilise encountered soft ground and enable TBM Florence to restart excavating the headrace tunnel.
TBM Florence has tunnelled about 150 metres and is currently located at a depth of approximately 30 metres below ground. A surface depression recently emerged in the ground above TBM Florence, which has temporarily delayed progress on this particular worksite. The depression is approximately nine (9) metres deep and continues to be monitored.
Importantly, the integrity of the tunnel, which is supported by a concrete lining and steel ribs, has not been compromised, and nor has the capacity of the TBM. The project team has paused the machine until about 10-15m of weak material in front of it is stabilised, prior to striking hard rock, when we expect normal tunnelling to resume.
Snowy 2.0 principal contractor Future Generation Joint Venture (FGJV) is drilling probe holes through the front of the excavation to understand the ground conditions immediately ahead of the TBM. Grout is injected in front of the excavation to improve any weak zones and limit any water flows. Grouting is well underway from TBM Florence, with 20 grout holes drilled to date in the current location.
FGJV is currently installing a slurry plant for the TBM that will mean the machine can switch from open excavation to a closed, pressurised mode. This will deliver stable excavation and efficient progress through the softer ground conditions, while enabling the TBM to switch back to open mode when in harder rock.
Stage two of the works to stabilise the ground in front and above the machine will involve ground improvement from the surface. Once the area is grouted, the depression will be backfilled and revegetated.
Snowy Hydro has been responsibly operating the Snowy Scheme in Kosciuszko National Park for decades and remains committed to careful and safe management of this tunnelling challenge in a sensitive environment.
The Snowy 2.0 workforce of more than 2,200 is continuing to achieve milestones across a range of work fronts as they build the huge pumped-hydro expansion of the Snowy Scheme.
At Lobs Hole, in the main access tunnel, works are continuing on multiple drill and blast cross tunnels. These will link with the ECVT, where TBM Kirsten has tunnelled 2.8km and has reached the site of the underground power station cavern complex. This is a great milestone for Snowy Hydro as we now have access to the excavation site from both ends of the cavern, which will be one of the largest and deepest in the world.
TBM Kirsten is setting a global standard in tunnel boring technology, just as the original Snowy Scheme developed rock bolting techniques that are still used throughout the world today. The machine will soon be modified to excavate the inclined pressure shaft on a steep uphill angle. Modifications include altering the levels of the TBM’s tanks and mechanical equipment so they are level when travelling up the 25-degree incline, and converting the walkways on the machine’s sides into steps and ladderways.
Meanwhile TBM Lady Eileen Hudson is being reassembled at the Talbingo adit with some new components including a cutterhead and shields. It will be launched into the mountain later this year to excavate the 6km tailrace tunnel, which will feed into Talbingo Reservoir.
Excavation of intakes at Talbingo and Tantangara is advancing steadily, along with the giant surge shaft on the Marica plateau that is already excavated to a depth of more than 20m.
Despite the ongoing challenges faced by all large infrastructure projects, Snowy 2.0 continues to achieve progress across a large number of remote work fronts.
Snowy Hydro remains fully committed to ensuring the local community and stakeholders are kept updated on this pumped-hydro mega project that will provide the National Electricity Market with 2,000 megawatts of on-demand generating capacity and a huge 175 hours of energy storage.
Caption: 3D imagery of surface depression above TBM Florence at Tantangara, created using photogrammetry technology
Caption: Snowy 2.0 project overview.
Caption: Talbingo adit, where TBM Lady Eileen Hudson is being reassembled for excavation of the tailrace tunnel.
High inflows to the Snowy Scheme, including the Jindabyne catchment, have been experienced for more than 12 months and are continuing due to the late snow falls and wetter than usual weather conditions.
Lake levels are approaching 100% and continue to rise, so Snowy Hydro has consulted with NSW Department of Planning and Environment (DPE Water) to make pre-releases into the Snowy River below Jindabyne Dam from 1am Saturday 17 December 2022.
Pre-releases will be greater than the environmental releases notified on Snowy Hydro’s website and may change at short notice in response to the weather conditions. Releases are expected to remain below 2,000 megalitres per day, but could increase in response to further weather events.
If Lake Jindabyne reaches 100%, it will trigger the operation of the spillway gates. Dam safety is paramount, and the spillway gates will automatically release water whenever the storage reaches or exceeds 100%.
For the community the most important message is to stay safe and well informed. The public can stay updated about flood alerts here:
