Early Engagement of an Independent Commissioning Coordinator Reduced Project Risks for Top Energy

The construction of a new substation at Ngawha for Top Energy was successfully commissioned in August 2020. As a project with multiple facets, stakeholders and several challenges, it proved beneficial to engage an independent commissioning coordinator to identify and mitigate potential risks to delivery.

Top Energy’s project to construct a new 33 to 110 kV substation at Ngawha had a compressed timeline and potential challenges that required proactive management. Initially engaged to project manage the construction, Edison’s scope was extended in March 2020 to provide an independent commissioning coordinator for the two 110 kV connections.

The project had multiple facets requiring the proactive coordination and support of our project manager including:

  • Inclusion of the Kaikohe Bus Extension.
  • Tendering and procurement.
  • Design management.
  • Civil construction works.
  • Interfaces between the power station contract, network requirements and electrical installation works.

In August 2020 the project culminated with the successful commissioning of the:

  • Kaikohe 110 kV Bus Extension: Comprising a new low-level bus, through a circuit breaker and current transformer set connected to a new 110 kV line.
  • Ngawha 33 to 110 kV Transmission Substation: Comprising of a new bus through two circuit breaker and current transformer sets, a new 80 MVA 33/110 kV transformer, a new protection scheme and a 33 kV Schneider GHA board.


The engagement of an independent commissioning coordinator at an early stage was critical in avoiding delays and unplanned events. Several challenges were identified, including unforeseen events like extreme weather and Covid-19, through to working with new SCADA technology, a new operations team, and an associated generation project. Importantly, it was the early inclusion of an independent commissioning coordinator that resulted in early detection of potential risks. Thus giving the project manager and team time to proactively manage and mitigate any project and timeline impacts.

The next project stage is to commission the 11 kV board and auxiliary power systems to the power plant. Edison will fulfil this role for Top Energy.


  • On time project delivery
  • Successful commissioning of 110 kV Bus Extension and Ngawha 33 to 110 kV substation

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Grant Lovie

Area Manager


Mike Stevens

Area Manager


Darryl Yorke

Area Manager


Gerald Dignan

Area Manager


Liam Doar

Design Manager