One of the major disadvantages of ground-based wind generators is that winds at that level can be notoriously unreliable. However, some 300 meters up, winds blow not only much more steadily but with more overall energy.
Inflatable wind turbine technology, spearheaded by the Magenn Air Rotor System (MARS), seek to take advantage of this phenomenon. The system consists of an inflatable cylindrical turbine tethered to the ground that spins about its horizontal axis, using angled vanes along its body to capture the wind for rotation. This rotation in turn generates power, which is funneled to the ground via power cable sin its tether.
The system also take advantage of the Magnus effect, where a spinning object creates a vortex of air around itself to various effects, to help create additional lift and to stabilize it in place.
One of the great advantage of the MARS system is that it can be placed almost anywhere--oceans, coasts, lakes, farms, deserts, suburbs, mountain areas, and so on—and still prove an excellent source of power. The designers hope that the MARS system can be used to provide power not only to population centers, but bring power to remote areas where it might be otherwise too difficult or too expensive to have. MARS can also be used in disaster-relief situations to provide ready power.
The MARS when fully developed is expected to have an efficiency rate of up to 60% (compared to the 25% or so of ground-based wind generators) and cost less per unit of energy than most other wind power solutions. It also produces no carbon emissions and is very environment-friendly, posing less hazard to local flying fauna. The tether and the turbine itself is made out of a Vectran material, which is stronger and lighter than steel.
If it does escape its tether, it has an automated deflation system which would bring the unit down to the ground slowly and safely. During times of turbulent weather, it can be more quickly deflated and reeled in by its tether.
Its thought that the MARS system could also be attached to ships, to be used to help drive the vessel’s propellers.
http://www.magenn.com/http://www.marinebuzz.com/2009/03/05/marine-applications-of-magenn-air-rotor-system-mars/ http://www.treehugger.com/files/2008/05/magenn-air-rotor-floats.php http://www.inhabitat.com/2008/06/04/floating-wind-turbines/
On The Magnus Effect:http://en.wikipedia.org/wiki/Magnus_effect