Lighter-than-air craft for energy-producing turbines

Abstract

A wind-based power generating system provides a wind energy converter for converting wind energy into another form of energy using a lighter-than-air craft configured to produce a positive net lift. The net lift includes both a net aerodynamic lift and a net buoyant lift. A tethering mechanism is configured to restrain the lighter-than-air craft with respect to the ground. The lighter-than-air craft defines an interior volume for containing a lighter-than-air gas, and the lighter-than-air craft has a fore section and an aft section. The tethering system has at least one attachment point on the fore section of the lighter-than-air craft and at least one attachment point on the aft section of the lighter-than-air craft. The lighter-than-air craft provides a stable aerodynamic moment with respect to a yaw axis about a center-of-mass of the lighter-than-air craft. The craft can be formed in a variety of aerodynamic profiles/shapes.

What is claimed is: 
     
         1 . A wind-based power generating system comprising:
 a wind energy converter for converting wind energy into another form of energy;   a lighter-than-air craft configured to produce at least one of neutral net lift and positive net lift to the wind energy converter, the net lift including a net aerodynamic lift and a net buoyant lift; and   a tethering system configured to restrain the lighter-than-air craft with respect to the ground, wherein the lighter-than-air craft defines an interior volume for containing a lighter-than-air gas, and wherein the lighter-than-air craft has a fore section and an aft section, wherein the tethering system has at least one attachment point on the fore section of the lighter-than-air craft and at least one attachment point on the aft section of the lighter-than-air craft, and wherein the lighter-than-air craft is constructed and arranged to generate a stable aerodynamic moment with respect to a yaw axis about a center-of-mass of the lighter-than-air craft.   
     
     
         2 . The wind-based power generating system of  claim 1  wherein the lighter-than-air craft has a cross-sectional shape at least in part configured as an airfoil.