Ngatamariki Steam Field Hero

Ngatamariki Steam Field

Geothermal power is a small but significant part of the energy generation capacity of New Zealand, providing approximately 13% of the country's electricity. New Zealand boasts some of the earliest large-scale use of geothermal energy in the world. When Mighty River Power (MRP) decided to build the Ngatamariki plant it called on Hawkins.

Mighty River Power’s goal: 

  • To build a plant to provide additional reliable renewable capacity and further diversify Mighty River Power’s generation portfolio.

What we did:

We were responsible for the design, procurement and construction phases of the Ngatamariki steam field project for MRP (as subcontractor to the EPC Contractor, ORMAT). This involved:

  • the pipeline design, including the production and hot and cold injection systems
  • construction of a 7m-wide corridor for the pipeline involving land formation and stabilisation
  • construction of six well pads
  • installation of approximately 6km of steel pipeline ranging from 450-900 nominal bore
  • installation of equipotential bonding along pipeline
  • construction of nine water storage and soakage ponds ranging from 100m3 to 6000m3 including all pond lining installation, trenching and installation of the HDPE cold injection system
  • electrical controls and instrumentation works at all well pads
  • installation of pipeline insulation
  • pre-commissioning of the pipeline and plant commissioning assistance.

Our role involved coordinating the various trades such as civil and earthworks, mechanical, electrical, controls and instrumentation, trenching and pipe insulation. Our productive and collaborative working style, which involved engaging the team through an understanding of core values, allowed us to do so successfully and was a key element in overcoming a number of challenges to complete the project.

Beat practice quality management was integral to the success of this project. In order to ensure quality standards were met, we interacted daily with our subcontractors and inspected activities prior to and during work as well as post completion.  Each activity was signed off by us and the relevant subcontractor. This provided a record of compliance and acceptance.

We successfully maintained a flexible and positive working environment with the client, designers, subcontractors and suppliers, enabling them to seamlessly solve day-to-day challenges. 

The outcome:

The plant complements Mighty River Power’s core hydro base, lifting the company’s geothermal energy production (measured on ownership interests) from over 30% to approximately 40% of its generation output, and taking total geothermal capacity under its operation above 460MW.

Hawkins has, once again, contributed to reducing New Zealand’s reliance on fossil fuels, building a plant that provides a clean source of energy and no pollution.