What are the advantages of Vertical Axis Wind Turbines?

One key advantages of VAWT is that they do not need to be pointed into the wind to be effective. This is an advantage on sites where wind direction is highly variable. VAWT also obviate the need for massive towers and can be mounted closer to the ground or on rooftops. As the generator is closer to ground, it is easier to maintain. VAWT's have lower start up speeds than HAWT's, typically generating power at windspeeds as low as 2 to 3 m/s and may be installed at places where tall structures are prohibited. VAWT's can take advantage of locations where mesas, hilltops, ridgelines, and passes funnel wind and increase wind velocity. VAWT's are also very quiet as they operate at low RPM's.