Watercraft with vertically collapsible vertical axis wind turbine and propeller flexible drive shaft

Abstract

A vertically collapsible vertical axis wind turbine may be used on land, or on a watercraft (e.g. a multihull such as a catamaran). The turbine may include a substantially vertical shaft; at least two vane supports mounted by the shaft; and at least two vertically collapsible material vanes supported by the vane supports, so that the vanes are movable from a first operative position in which the vane material is substantially taut, to a second inoperative position in which the vane material collapses. The vane supports are positioned, and the vanes are constructed, so that the wind turbine preferably has a Savonius or an open helix configuration. When used on multihull watercraft a propulsion mechanism is mounted between two of the hulls, and there is an operative connection between the wind turbine shaft and the propulsion mechanism. The operative connection may be a flexible shaft having at least about a 70 (e.g. about 90) degree bend therein. The propulsion mechanism may be a horizontal large diameter propeller mounted so that during normal loading of the watercraft roughly half of the propeller is in water and roughly half is out of water. Optionally, at least some portions of the hulls which normally engage water are made of marine grade polyethylene, which has low friction.