Science: Noisy Windmill

Shushing the swish-swish

The world's largest windmill began operating last year in Boone, N.C. With blades that stretch 60 meters (200 ft.) from tip to tip and can generate 2,000 kw of electricity, it is also, it seems, the world's noisiest. Besides dominating the scenic Blue Ridge Mountains landscape—or despoiling it, as some of those living near by complain—the monster rattles windows, bounces cups and saucers and creates an irritating swish-swish.

Surprised by this unexpected noise pollution from an experimental power plant that was supposed to be almost entirely free of environmental headaches, engineers from the U.S. Department of Energy and NASA flocked...