NZ Windfarms has applied to expand the Te Rere Hau wind farm, asking for consent for another 56 turbines.

In 2005, the company gained consent to build 97 turbines, 43 of which had been built by May this year.

The extension encompasses 300 hectares on the Tararua side of the ranges, connecting with the Palmerston North section.

The turbines applied for are 47 metres high, with two blades.

Consent applications have been lodged with Tararua District Council and Horizons Regional Council.

While a successful application would open the way for 153 consented turbines, NZ Windfarms chief executive Stephen Cross said there were no "immediate plans" to build that many, because only 97 turbines had been bought.

"All we've committed to at the moment is 97."

Mr Cross said the new area was identified as having better wind than some of the consented turbine sites in lower areas.

"Some of those may end up on the new patch of land."

Asked if the company would apply to have the application called in by Minister for the Environment Nick Smith, Mr Cross said the company intended to go through the "normal process".

Last year, Dr Smith called in the 122-turbine Turitea Wind Farm project. Board of inquiry hearings are to be held for that project next month.