HV contract to power Australia’s largest seawater desalination plant

Olex recently won a $43 million contract to supply the high voltage underground cable link that will power Australia’s largest seawater desalination plant, currently under construction in Victoria. The contract covers the supply of around 260 km of 220 kV XLPE cable, made and tested as a 275 kV cable, to Thiess DegrÈmont. Thiess DegrÈmont is contracted by the Victorian Government to design and construct the $3.5 billion Victorian desalination project to deliver up to 150 billion litres of water a year to Melbourne and regional communities.

The Victorian desalination project will deliver the largest desalination plant in Australia. Located near the town of Wonthaggi, south east of Melbourne, it will be capable of providing more than one-third of Melbourne’s annual water supply from a source that is independent of rainfall. Construction commenced in September 2009 and will be completed by the end of 2011.

The Victorian desalination project includes an 84 km underground pipeline to connect the reverse osmosis plant to a transfer main and then back to the reservoir. The electrical power required by the new plant will be supplied by the 87 km long underground cables co-located with the pipeline – creating one of the world’s longest high voltage AC underground links operating at this power level. An underground link was the preferred option for the project since it is both more energy efficient and secure than overhead lines. It will also have the least impact on landowners, farmers and other people living and working in the area.

Olex will produce 225 km of the underground cable locally at its Tottenham facility in Victoria. It will be manufactured on equipment recently installed as part of a $20 million upgrade that now enables the plant to produce XLPE (cross-linked polyethylene) cables up to 500 kV. The remaining length of cable will be supplied by the Nexans factory located in Charleroi, Belgium.