"This report shows the potential is very high and rapid advances in technology are making it possible to tap more of that potential," says energy minister Trevor Mallard. He adds that the report, prepared by Energy Link and MHW NZ, allows the government to consider a significant role for wind generation in the future. "This is a clear indication that government realises that the wind industry is ready to substantially contribute to the development of an environmentally responsible and economically competitive energy policy," says James Glennie, chief executive of the New Zealand Wind Energy Association.
Concerns about how to integrate wind into New Zealand's current mix of hydro and thermal generation have otherwise been an issue, with problems encountered with the clustering of wind farms in the Tararuas. National grid operator Transpower has had to review its operating procedures and the capacity of nearby grid lines.
New Zealand has some unique constraints that have held back development despite good wind resources. Unlike European countries with close links to neighbouring grids, it operates an isolated system which is further split between the two islands. The variations in demand and supply from wind power can be offset by the large amount of hydro-based generation, but there are concerns about integrating large scale development into the national supply.
New Zealand operates on a 50 Hz frequency, with a regulating station designated to maintain this within a 0.2 Hz range. The report notes that "high levels of wind integration potentially cause large, rapid swings in generation which in turn can create rapid frequency changes, possibly to the point of being too much for the regulating station to cope with." New Zealand currently has 175 turbines with a capacity of 168.2 MW. The predicted market share of 20% would take that to 2000 MW, requiring another 800-2000 turbines.