Te Rere Hau wind farm to cut down the hours it operates 

The owner of a Manawatū wind farm that makes “annoying” noise will cut down on the amount of time the turbines operate.

Environmental commissioners are re-evaluating noise rules for the Te Rere Hau wind farm on the Tararua Range after a saga that has included court action and the Palmerston North City Council receiving 1700 noise complaints from residents.

Neighbours have complained about a “whining” noise, a “whoosh” and a rumble like a train that never arrives.

A hearing in Palmerston North started on Tuesday, where representatives from NZ Windfarms, the city council and noise experts are debating what rules there should be to control noise.

This follows the city council losing a case in the High Court against NZ Windfarms.

NZ Windfarms chief executive John Worth said the company radically changed its approach recently. Instead of running the turbines as often as possible, the company planned to run them only when the revenue was worthwhile.

Worth said the company’s profitability was driven by being able to harvest wind energy when the price for it was high. There was typically a high price when wind speed was low.

Worth said the wind farm was fighting to be profitable. The company had a loss of just under $400,000 this year and had restructured its operation.

However, the company’s plans clashed with a restriction the council wants to impose. NZ Windfarms does not object to wind speeds needing to be at least 6 metres per second at night before the turbines kick in, but the council wants to push that up to 8m per second.

Worth warned this could “undo much of the progress we’ve made” with neighbours, as well as reducing revenue.

Worth said the company was working with neighbours to come up with solutions that could suit everyone. He acknowledged their frustration. “The duration of the noise discussion with this organisation is regrettable.”

The council is also pushing for the acceptance of a method recently adopted in Britain to measure swishing-type noise. NZ Windfarms doesn’t accept that approach.

Lawyer for the Palmerston North City Council John Maassen said the council believed decision-makers should do more than just “slavishly” adhere to the 2010 New Zealand noise standard. Sticking just to the noise standard created a risk of unreasonable noise being allowed to continue, he said.

Lawyer for NZ Windfarms Vicki Morrison-Shaw said noise had been a longstanding problem for the farm.

However, the company’s failure to live up to expectations did not mean it had been flouting the law over the years.

The company acknowledged its operating approach and performance had been “less than optimal in a number of respects”. It had been technically compliant with the law, and there were recent improvements.

“NZ Windfarms is committed to improving its performance – economically, environmentally and, especially, socially.”

Morrison-Shaw said NZ Windfarms supplied power to about 18,000 households and $2.5 million to the local economy each year.

Noise expert for the city council Tom Evans said some of the troublesome noise applied to specific wind directions. It was not associated just with noise heard downwind. The company could do more analysis about that.

He suggested the New Zealand noise standard didn’t adequately reflect the impact of annoying noise. The approach in Britain dealing with some types of noise could work better.

He also said the sound output from each two-bladed turbine at Te Rere Hau was surprisingly loud – about as much as would be heard from larger three-bladed turbines.

Another noise expert for the city council, Nigel Lloyd, commented on expectations. He said it was anticipated in 2005 there would be no adverse effects in some areas.

“Unfortunately, it didn’t turn out that way at all.”

Neighbours are expected to present evidence on Wednesday.