Scheme Modernisation Project

Snowy Hydro has embarked on a substantial modernisation program, which will maximise the value of the Snowy Mountains Scheme hydro-generation assets.  The program will deliver engineering solutions, which underpin our trading strategies and increase our flexibility in responding to future operating and maintenance strategies.

Modernisation of the Snowy Mountains Scheme Power Stations will introduce advanced controls and protection systems technology across the entire Scheme.  Ageing and high maintenance plant components such as circuit breakers, high voltage transformers and cables will be replaced with modern components.  New turbine runners will optimise generation capabilities and improve efficiency of water utilisation.

Major maintenance of the Schemes extensive trans-mountain tunnel systems, which deliver water from lakes to the power stations, is in progress to ensure the ongoing safe and reliable management of water utilised by the Snowy Mountains Scheme.  Innovative maintenance techniques and engineering solutions for water conveyance tunnels are enabling future tunnel maintenance requirements to be substantially reduced.

Update - March 2013

Work on Snowy Hydro’s $400 million Scheme Modernisation project continued during 2012 and into 2013.

The Kosciuszko region was completed this year. Jindabyne Pumping Station pumping units had their control and protection systems upgraded. In addition this year Guthega Power Station, the oldest power station in Snowy Hydro’s fleet was also completed with the upgrade of its second generating unit. The outage of this unit commenced in late February and return to service occurred in August 2012. Unit 1 having been successfully upgraded in 2010.

The major works in the Lower Tumut region were completed in 2011. The six generating units at Tumut 3, the largest Power Station in the Snowy Hydro fleet have all been modernised and upgraded with the turbine runners replaced, new governing, control and protection systems installed and all other mechanical and electrical components overhauled. The upgraded units at Tumut 3 are now capable of providing between 25 and 50MW of additional capacity each. Blowering Power Station control, protection, governor and excitation systems were replaced in 2009 to provide reliable remote operation.

Twenty one air-blast generator circuit breakers across the Scheme have now been replaced with modern reliable SF6 insulated breakers. The new breakers reduce maintenance requirements, increase overall availability, and improve reliability. In addition, all 11kV distribution circuit breakers across the Scheme have been replaced.

Detailed planning work has now commenced for the Upper Tumut project phase. The works associated with the replacement of main transformers and 330kV cables for Tumut 1 underground Power Station is underway and the first four transformer replacement have been successfully completed. The replacement of the fifth transformer has commenced with remaining transformers to be replaced over the coming 9 months.

Delivery of all four new turbine runners for Tumut 2 Power Station has occurred. The first of Tumut 1 turbine runners will arrive in early 2013 with the delivery of the remaining runners for Tumut 1 occurring over the next 12 months, prior to the scheduled outages commencing in 2014.

The initial unit upgraded in the Murray region, Unit 14 at Murray 2 Power Station was completed in Early 2008. 2012 has seen a return to the region with the controls and protection upgrades in Murray 1 with unit 8 completed in December 2012 and unit 7 due for return to service in Early January 2013. The control and protection upgrade outages at Murray 1 will continue through 2013, and 2014 until early 2015 when the last controls and protection upgrade and the first mechanical refurbishments of the Murray 1 Power Station is planned to take place. The contract for the design and purchase of the Murray 1 turbine runners has been signed with design of the first turbine runner under way and delivery of the first runner is scheduled to occur in February 2015 prior to commencement of the first mechanical upgrade outage.

All of the major overhauls and upgrades have all been completed without significant injury or incident. Outstanding teamwork, dedication, and skill has been displayed by all involved, contributing to the successful implementation of a complex, high quality finished product. The project represents an investment in maximising asset value through increasing turbine capacity and efficiency, maintaining long term reliable operational capability and modernising the Scheme assets through replacing aging technology.