Amethyst Hydro Scheme


Amethyst Hydro Scheme

Click here for the Amethyst Project Sheet PDF


HydroWorks was involved in the design and manufacture of the 8 MW hydro station at Amethyst. This station was commissioned in July 2013 and has a number of ‘firsts’ in New Zealand and Australia:

  • It is the first 6 jet vertical Pelton turbine
  • It is also the first large Pelton turbine that uses deflector governing to maintain grid stability

Grid Support

The electricity grid south of Hokitika on the scenic west coast of NZ is vulnerable to local feeder trips. There are several small hydro stations south of Hokitika, but these are unable to maintain grid stability in the event of a feeder tripping out.

Amethyst has been designed to accept up to 7 MW of local load in a black start condition, and reject up to 7 MW of load whilst transitioning stably to local control and islanded operation. Trials have shown this concept to work well. Spears are used only to economise on water, with turbine speed being controlled by the deflectors.

Client: Amethyst Hydro Ltd
(Westpower 88%, Hari Hari Hydro 12%)
Location: Hari Hari, New Zealand
Scope: Mechanical design, manufacture and installation of 6 jet vertical Pelton
Head: 394 m
Discharge: 2.1 m3/s
Nominal Output: 8,000 kW
Commissioning: 2013

Amethyst Intake

Amethyst Intake

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6 jet vertical Pelton design

Amethyst distributor - bending stress - symmetry section - all segments 600_600

Detailed analysis of  the distributor


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Installed turbine/generator unit


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The turbine runner seen from the draft tube

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High quality Rexroth Hydraulic Power Unit

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Amethyst Switchboard    

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One of the Amethyst cubicles