Another helium-filled post - this time it's a helium-filled blimp that houses a horizontal-axis wind turbine [source: gizmag]. Altaeros Energies recently released a video of their prototype Airborne Wind Turbine in action:

So what is the attraction of airborne wind turbines? Once you are beyond the Earth's boundary layer you have access to stronger and more dependable wind currents. Therefore, an airborne wind turbine promises relief from the weak and intermittent winds found at ground level. It's still early days for airborne wind turbines and whether they can deliver on their promise remains to be seen.