Tiwai deal allows wind farm to progress

The Kaiwera Downs wind farm is to get considerably bigger as its second stage is constructed....
The Kaiwera Downs wind farm is to get considerably bigger as its second stage is constructed. PHOTO: STEPHEN JAQUIERY
Mercury Energy will spend nearly half a billion dollars on the second stage of its Kaiwera Downs wind farm, saying the project went ahead only when it struck a deal to sell power to the Tiwai Point aluminium smelter.

The company announced plans yesterday to go ahead with the larger second stage of the wind farm development.

The company built 10 turbines in stage 1, which started turning near the end of last year after a year’s construction.

The second stage will be bigger, higher and will take longer to build — 36 turbines, with a blade height of 156m and construction to take until the end of 2026.

Mercury Energy executive general manager portfolio Phil Gibson said the company’s agreement with Rio Tinto, which owns Tiwai Point, allowed the expanded wind farm to go ahead.

The amount of power produced at the wind farm was more or less what was needed for the company to supply Tiwai Point.

Phil Gibson
Phil Gibson
It may not blow all the time at the agreed production levels but the agreement was very important as it gave certainty and confidence for the generation market, Mr Gibson said.

From there generators could look at other renewable schemes to boost electricity generation as demand continued to increase, especially in Southland.

Interest rates and exchange rates also had an impact on the decision to proceed with the scheme.

The price of turbines and blades had increased by 40% in four years as demand ramped up. Prices were expected to plateau as more came on to the market. Shipping costs had also risen.

The new turbines were about 15m higher than the turbines built in the first stage but would still produce the same amount of power. They were higher because of ground layout. The new turbines will be southeast of the first site.

Major investment from Transpower would enable more power to be shipped out from the area.

A construction workforce of about 150 would work on the build, with parts shipped in via the port in Bluff.

Second helpings

 - 36 new wind turbines to be built

 - Site located southeast of stage one

 - Produce 155MW — equivalent of power for 73,00 homes

 - Farm part of contract to supply power to Tiwai Point aluminium smelter

 - Blade tip height 156m, about 15m higher than stage 1 turbines

 - Cost of $486 million, with construction workforce of about 150.

 - Construction to start by the end of this month, expected to conclude end of 2026