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Homeowners could soon get part of their power supply from a small wind turbine fixed on their roof, if a power company's trial shows potential.
The electricity distribution company Vector yesterday began the trial at Waitakere City Council, where a micro wind turbine has been installed on the roof of the civic centre from where it will feed electricity directly into the building.
Vector chief executive Mark Franklin said the company wanted to assess whether urban micro wind generation could provide a renewable energy solution.
Mr Franklin said Vector would trial up to 10 of the micro wind turbines in a range of locations in Auckland and Wellington, where it operated electricity networks, to see how they performed in the urban environment and assess their technical viability and commercial potential.
Electricity demand was predicted to continue to grow at about 2 per cent a year and small-scale distributed generation initiatives such as solar and wind energy could grow strongly in coming years to help meet this growth, he said.
The company had an exclusive arrangement with the turbine maker Renewable Devices Swift Turbine, of Edinburgh.
The Swift turbine had already been successfully installed in the UK and other countries including on residential homes, council buildings and supermarkets.
Each trial site would be assessed for its average wind speed, the amount of energy generated, noise and visual impact and for any effects the turbine might have on the operation of Vector's local electricity network.
The Swift turbines were designed to be mounted directly on buildings and operated well in the relatively low speed and turbulent winds that occurred at rooftop level.
They have five blades with a diameter of about 2m and weighed about 50kg.
With an output of 1.5kW they could provide between 2000 and 3000KW-hours of electricity a year, about a quarter of the average New Zealand annual household's electricity needs.
The turbine was virtually silent with a sound output of less than 35 decibels, well within local government noise emission standards.
Clive Bull, group strategic initiatives manager, said if the trial proved successful the price of the turbines could, with big orders, come down to about $8000.
In Britain the turbines were working well and the manufacturers claimed they had a maintenance-free life of 20 years. Waitakere Councillor Penny Hulse said the trial was a logical extension of Waitakere's eco city status and its commitment to reduce greenhouse gas emissions by 85 per cent by 2051.
"We need to be smarter about the way we operate and there are great opportunities for us as a city and for local businesses in trialling new technologies such as this wind turbine."
Ms Hulse did not envisage any problems getting consents for installing wind turbines and if the demand was sufficient the council might waive the fees as it had done for solar hot water systems and rain water tanks. Energy Minister David Parker welcomed the trial and said Vector's move was in line with a burgeoning number of companies taking steps towards carbon neutrality and improved sustainability.
"Micro wind generation has the potential to improve our energy security and reduce greenhouse gas emissions.
"It could also help interested consumers reduce their power bills through use of a free energy resource, in a similar way to solar hot water systems."
