Abstract :
XERXES, a vertical-axis sail-bladed wind turbine with no bending moments in the primary load path from the inception of the distributed airloads on the sail membrane to the delivery of the integrated loads to the hub, is described. This structural system reduces the blade cost and weight by estimated values of 84% and 94%, respectively. Furthermore, because of the sail blade´s ability to camber itself automatically, the aerodynamic efficiency of the turbine improves by an estimated 25% increase in power coefficient. Reduced turbine cost, increased energy capture, and increase in economic size of practical turbines combine to extrapolate energy costs of less than 0.02$/kWh
