Quiet wind turbine provides partial power for homes at an install cost of roughly $10,000.

Originally designed by Scotland-based Renewable Devices, the Swift wind turbine is being sold in the US by Cascade Engineering of Grand Rapids, Mich.

Unlike many existing small wind turbines, the Swift turbine is designed to reduce noise. At seven feet in diameter, it consists of five thin blades encircled by a ring. The ring reduces vibration and diffuses the noise to a level of less than 35 decibels.


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