Turning wind power on its side

摘要

Wind turbines are springing up in all sorts of places around the world, from China to California, but most of them have the same basic design: the blades rotate about a horizontal axis, as in an old-fashioned windmill. Such turbines can generate electricity at a cost not much higher than non-renewable, fossil-fuel sources-provided the wind is blowing, that is. But if proponents of a rival design are to be believed, electricity can be generated from wind even more cheaply, using turbines that rotate about a vertical axis, like a playground roundabout.