Benmore Substation

Allied Concrete have set up a mobile plant at Otematata in the Waitaki Valley to supply Transpower’s Benmore substation. Allied Concrete are supplying Christchurch based Leigh’s Construction who are sub – contracting to Mainzeal.

Christchurch Press - 01/09/2010:
A massive pour of concrete at Benmore marks the first big step this side of Cook Strait in a $672 million upgrade of the inter-island power link. Seventy truckloads - 340 cubic metres - of concrete containing cement from the nearby Otematata quarry were poured yesterday at national grid company Transpower's Benmore substation on the upper Waitaki River. The foundations of the new transformer bay were laid by 30 workers between 7am and 5.30pm.

The bay will eventually hold three 330-tonne converter- transformers, which help to change the current and voltage of the power so it can be sent north and under Cook Strait to the Haywards substation in the Hutt Valley.

The high-voltage direct-current (HVDC) upgrade is essential to ensure enough hydro-generated power gets to the North Island and also provides a buffer for South Island consumers reliant on northern electricity when the hydro lakes are low. The revamp will increase the HVDC's steady capacity from 700 megawatts to 1000 megawatts (MW) by 2012 and 1200MW by 2014.

Transpower spokeswoman Rebecca Wilson said about 40 people were working at Benmore on the project. "During peak construction periods, this could be up to around 100 people. Much of the civil works there - plumbing, drainage, concrete, structural - are coming from the local South Canterbury and Otago engineering and construction resources." Work began at Benmore in June and the major pieces of electrical equipment were scheduled for installation between January and December next year, she said.

The HVDC work is part of a 10-year upgrade of the national grid expected to cost $3.5 billion.