Securing Power Supply for Transpower’s Auckland and Northland Grid

In order to meet the future power supply needs of New Zealand’s Auckland and Northland regions, a vital part of the 220 kV Otahuhu–Whakamaru A and B transmission lines needed to be replaced. After 68 years of service, the conductor of the Otara to Flatbush section had reached its end of life.  National grid owner and operator Transpower chose Lamifil’s TASCR Curlew conductor as the most cost-effective and low-noise solution.

End-of-life section of a vital line

Auckland and Northland rely on power generated from the south island. The Otahuhu–Whakamaru 220kV A and B lines are crucial for the supply of electricity to the region. Prior to further line upgrades, a five km stretch from Otara to Flatbush was given priority for reconductoring. The conductor of that section had corroded significantly due to high levels of salt in the coastal air.

A fast, effective and low noise risk solution

Transpower conducted a multi-criteria analysis to assess the best reconductoring option. One of the key criteria was potential conductor noise.  The area under the transmission lines had become densely populated since the line was first built back in the 1950s. The TASCR Curlew was chosen as the most cost-effective option, providing the lowest noise risk and requiring minimal tower strengthening.

In total Lamifil will deliver 43 km of TACSR Curlew type conductor. The conductor features an Alu cladded steel core with TAL alloy and heat resistant grease. The combination of trapezoidal wires and surface treatment mitigates corona noise effects.

Helping to meet the ongoing electricity needs of New Zealand

Lamifil is continuously looking for ways to answer specific customer needs. Working together with Transpower, it was able to propose a conductor that met the criteria of the cost-benefit analysis and environmental effects.

The replacement of the conductor section is expected to start by mid-2021 and to be completed by 2023. Lamifil is proud to contribute to this project, which will help Transpower to maintain and develop New Zealand’s transmission network to ensure it meets the ongoing electricity needs.