CABLE INSTALLATION –
HARAPAKI WIND FARM

Location: Napier region

Service: Wind farm cable installation

Date started: November 2021

Date completed: April 2023

Challenges

Located 35km north of Napier on SH5, Meridian Energy’s Harapaki wind farm will be one of the biggest in New Zealand, in the most challenging environment.

The civil contractor (a JV between Hick Bros Civil Construction and Spartan Construction) needs to trench 68km to install cables in trefoil formation to connect the turbines on Harapaki wind farm.

They decided to use Marais Laying NZ’s services to trench and install the cable in the trench.

Trenching must be performed in the roads going from the substation to each turbine and Meridian Energy wanted a narrow trench – 350 x 1,050cm (up to 1,500cm).

The topography around this project is unique with narrow roads, steep hills, and multiple parallel trenches.

The project is also located at 1,100m above sea level which means high altitude weather.

Solutions

Marais Laying NZ proposed the use of a trenching machine named ST2, coupled with 2 other machines - a wrapping machine to maintain the trefoil and the RC320 to carry the 3 cable drums on site.

One other key solution was the laying box, specially designed for this project to install cables and sand automatically in the trench.

Result

This project led us to introduce a new range of solutions for cable installation on wind farm projects by increasing safety when transporting cable drums on steep hills using the RC320 machine. By using the laying box, we avoid having any employees working in the trench and the cable is automatically installed. Finally, our wrapping machine secures the position of the trefoil.