Abstract: A wind turbine electrical-generating system with air-directing vanes in the forms of sheaths over structural members crossing the sir discharge opening of the wind turbines. The turbines also have associated shroud assemblies which support the structural members and which cooperate with the vanes to provide superior performance.

Abstract: A vertically sectioned cylindrical accelerator for mounting pairs of wind turbines respectively on opposite sides thereof has a covering of twin-sheet thermoformed plastic panels which are smooth on the outside but carry a multiplicity of small cone-shaped projections on their interior surface. The panels are mounted on a structural member by a single central bolt for free expansion and contraction with variation in ambient temperature. The panels are manufactured in a twin-sheet thermoforming operation wherein one sheet is maintained with a smooth surface and the second sheet is provided with the cone-shaped projections, the two sheets being fused together to form an integral panel of lightweight and high strength characteristics.