Single blade turbine quieter

QUIETER: A new single blade wind turbine makes less noise than a two or more blade equivalent.
QUIETER: A new single blade wind turbine makes less noise than a two or more blade equivalent.

A relatively quiet single-blade wind turbine could be on sale next year owing to new government funding.

The turbine is being developed by Dunedin company Powerhouse Wind in partnership with Otago Polytechnic.

The project has secured a $368,000 grant from the Technology Transfer Voucher scheme run by the Ministry of Science and Innovation.

Powerhouse Wind director Bill Currie hoped the turbine would be available by about July next year. This depended on getting matching investment funds.

Currie said one of the features of the turbine was the low amount of noise it generated.

He said most turbine noise was made by the tip and trailing edge of a blade. A single blade meant this noise was reduced.

He said the single-blade design also meant they ended up with a much wider blade.

This also reduced noise because the airflow over the blade was smoother and created less turbulence.

The turbine blade was fitted to a "teeter bearing" so it could change its angle in response to changes in wind speed. It could make more efficient use of strong and gusty wind.

Currie said if the wind level was too high the blade could tilt out to horizontal to prevent it getting damage.

He said the turbine would run with a wind speed of up to 90km/h.

Alistair Regan, general manager of the Otago Institute of Design at Otago Polytechnic, said it was one of the most exciting technologies being developed in New Zealand.

Other projects being undertaken at the Institute of Design include developing a special computer mouse and simulating what happens when a bullet goes through a body.

Stuff