By Lynda Myer
While Australian hydropower project Snowy 2.0‘s first tunnel is completed, reports show that one of its contractors is up for sale and it can cause a delay in project’s delivery.
Being located at Lobs Hole in the Snowy Mountains in New South Wales, the main access tunnel with 2.85km length has been completed by tunnel boring machine (TBM) Lady Eileen Hudson.
Installing1,422 concrete rings by the TBM, which comprise 12,798 individual segments that were manufactured locally, the intended tunnel has been lined.
Connection to the adjacent emergency, cable and ventilation tunnel, is done through four cross passages, whereas this tunnel also has four cross tunnels and a turning bay to facilitate construction access around the power station complex.
Following completion of this tunnel, the team will access to the site where it is due to create the enormous cavern 800m underground that will house the power station.
As part of the 2,000MW pumped hydro expansion of the Snowy Mountains Hydro-electric Scheme, digging of over than 27km of waterway tunnels is up to this 11m diameter TBM that is one of a trio of machines, while in September 2021 the project’s second TBM Kirsten was launched and TBM Florence as the third one was commissioned in March this year.
Considering the completion of tunnel’s boring process, the main access tunnel is the determined place for dismantling of the TBM conveyor belt.
Also in order to excavating cross passages and tunnels to gain access to the power station complex, which is going to include a 251m long, 52m high machine hall cavern and a 223m long, 46m high transformer hall cavern, drill and blast activities are ongoing.
Providing water to be released for energy production at times of peak demand and then pumping back to the top storage when there is excess renewable energy in the system, will be the main advantage of this project.
The 2025 is the scheduled date for first power generation from the scheme, followed by progressive commissioning of its six generating units.
According to Snowy Hydro acting CEO Roger Whitby: “The TBM Lady Eileen Hudson and our teams from Snowy Hydro and contractor Future Generation Joint Venture have done a great job to complete this critical tunneling task.”
He also added: “Work across the project continues to move ahead rapidly and this tunnel boring machine is now being dismantled so it can be moved to the Talbingo adit, where it will be reassembled with some new components for excavation of the 6km tailrace tunnel.”
Additionally, delivery of the tunneling works for project promoter Snowy Hydro, is undergoing by principal contractor Future Generation joint venture – comprising Webuild, Clough Group and Lane Construction.
However, Clough Group, the Australian engineering and construction firm, is reported to be up for sale by South African parent company Murray & Roberts, and as reported by Renew Economy, Murray & Roberts revealed in September that Clough had no working capital facility.
Due to such issues the delivery of the massive federal government-backed pumped hydro project, can face some delays, while it also encountered mounting financial costs. Although the budget of A$5.1bn (£2.9bn) is the latest price tag for this project, the real figure for the project’s all-up cost could be nearer to A$10bn-plus (£5.7bn-plus).
This is because the underground power station and tunnels alone would cost more than $6bn (£3.4bn), without taking into account the cost of the transmission connections.
