Fewer mechanical parts and simpler construction than conventional turbines result in less service needed and a longer life span.
VAWTs are omnidirectional, meaning the direction of the wind does not have an impact on the performance. They do not need to be rotated to face the wind to maximize energy output as the wind direction changes. This eliminates the need for yawing mechanism.
The generator, which is generally in line with the rotational axis, can be placed at ground level. This allows for easier access and less weight at the top of the turbine.
Placing the generator at ground level makes a larger diameter generator more feasible than if it were in the hub. By allowing the diameter of the generator to be larger, the spinning rate of the axis can be lower, and hence eliminating the need to use a gearbox for gearing up the speed.