Genesis Energy’s Hau Nui Wind Farm is located in the hills south of Martinborough in the Wairarapa. Its location is ideal for a wind farm, as wind currents are funnelled and accelerated through the nearby Cook Strait and over the Rimutaka Range.

The wind farm’s 15 turbines have a combined capacity of 8.65 megawatts. They supply enough electricity into the local network to meet the annual needs of about 4,200 homes in the Martinborough area, and depending on demand and output, as far north as Greytown.

Hau Nui’s original seven Enercon E-40 wind turbines, installed in 1996, are third generation wind-energy technology. The additional eight turbines installed in December 2004 are the latest versions of this model.

Genesis Energy are currently assessing possible expansion of the wind farm.

Turbines

The E-40 is a variable-speed machine. The rotor, driven by three blades, is directly linked to the generator, allowing for rotation at speeds varying between 18 to 38 revolutions per minute. The gearless generators are designed with as few moving parts as possible and the absence of a gearbox means limited possibility of oil leakages and need for oil changes.

Each blade has its own electronic pitch control system, which automatically adjusts the angle of the blades to the wind to maintain a constant power output.

The turbines will generate electricity in wind speeds between 10 kilometres per hour (kph) and 120 kph. When wind speeds exceed 120 kph the turbines automatically shut down to avoid damage.

Visit

The wind farm is 20 kilometres from Martinborough and is signposted from there.