Zone substations and transmission lines

What is a zone substation?

Zone substations form an important part of Western Power’s network as they transform high voltage electricity (transmission) to lower voltage (distribution) which is then sent out to homes and businesses.

Western Power works closely with the local community to determine the most appropriate screening and landscaping techniques to mitigate the visual impact of a substation. We will be involving you in this process as the project progresses.

Example photographs of existing substations and screening methods

Three to six months after planting

Three years after planting

Transmission lines and cables

Transmission lines and cables are the backbone for transporting electricity in the South West Interconnected System.

Transmission power cables are significantly more costly than overhead lines, and if Western Power is to implement a cable solution, a robust justification is required. An underground cable connection is approximately five to six times more expensive than an overhead line. As an indication, a double circuit overhead line is estimated to cost approximately $5 million to install, as opposed to $25-30 million for double circuit underground cables. Maintenance costs for the coastal environment in Geraldton will be factored into the cost of overhead lines over the life of the asset. Western Power will also consider all technical, environmental and social issues with overhead lines, including investments made by the City of Greater Geraldton to visually improve the area, when selecting the preferred option.

Example 132kV transmission line

Please note that design has not yet been undertaken for this project and, as such, these photos are indicative only.

Below - transition structure - structures like these are required at points where lines convert from underground to overhead and vice versa.

 More information