Patent ID: 6926491

Claim:
A vertical-axis-wind-turbine comprising: (a) a vertical tower; (b) a tower-collar disposed rotatably on said tower; (c) a horizontal arm attached to said tower-collar; (d) a mast attached to said horizontal arm; (e) a mast-collar disposed rotatably on said mast; (f) a boom secured to said mast-collar; (g) a sail, attached to said mast-collar and boom; (h) a first and second motorized sail-restraint controllers attached to said horizontal arm; (i) an inner adjustable sail restraint secured to said first motorized sail-restraint controllers positioned between said tower-collar and said mast-collar; (j) an outer adjustable sail restraint secured to said second motorized sail-restraint controllers positioned between said mast-collar and an end of said horizontal arm; whereby when said sail is driven by wind the sail is restrained from moving freely by the adjustable sail restraints, and whereby the inner adjustable sail restraint causes the sail to gybe at an earlier time than would otherwise occur; and whereby the outer adjustable sail restraint restrains the sail during its gybe, thereby capturing the energy of the gybe that would otherwise be lost, and whereby said sails that are moving into the wind are feathered, so that the vertical-axis-wind-turbine rotates in only one direction, regardless of the direction of the wind; and whereby the position of said adjustable sail restraints may be adjusted by said motorized sail restraint controllers so that said adjustable sail restraints do not restrain said sail, allowing said sail to be feathered during excessive wind speed.