In the past two weeks, Transpower commissioned both of the Clyde-Cromwell-Twizel circuits — part of Transpower’s significant Clutha Upper Waitaki lines project (CUWLP) in the Otago, Southland and Waitaki regions.
CUWLP director Roy Noble said the completion of the
"thermal upgrade" on the Clyde-Cromwell-Twizel circuits was a major milestone for Transpower.
The upgrade enabled electricity to run "hotter" down the line and this meant more electricity could be carried.
The work required initial assessment of 252 pylons over more than 100km of mountains, ridges, paddocks and rivers, he said.
Measures included novel solutions, earth clearances, strengthening of pylons, and lifting or re-tightening the electrical wires to ensure distances from the earth were compliant.
"This work has required significant innovation within a compressed timeframe.
"It is a great collaborative effort by the Transpower, Electrix and our engineering consultant teams."
The long-term outage required to duplex the Roxburgh-Livingstone circuit, starting next month, would now able to take place with little impact to the transfer of electricity.
The CUWLP project is part of Transpower’s work to decarbonise New Zealand, and shift the country’s renewable energy from Manapouri, Roxburgh, Clyde and any future renewable energy projects to the whole country.
The project is expected to be completed in May 2022 and will increase northward transmission capacity for New Zealand from around 600MW at present to about 1000MW.
In all, there are 688 pylons, 900km of wire, and 26,000 insulators over a length of more than 280km.
