[Nate]

The Darrieus operates differently than the common propeller turbines by rotating around the central shaft. This enables the generator to be placed at the bottom, facilitating easy maintenance.

By contrast, a conventional design has all of the force of the wind attempting to push the tower over at the top, where the main bearing is located. Additionally, one cannot easily use guy wires to offset this load, because the propeller spins both above and below the top of the tower. Thus the conventional design requires an extremely strong tower that grows dramatically with the size of the propeller.

In overall comparison, the Darrieus design puts much more of its weight (and cost) into components that actually generate power, the blades, and much less into supporting them. Additionally the generator and main bearings are located at the bottom, where they can be easily serviced. A final advantage to the design is that the blades typically spin at a speed near that of the wind, which birds do not have a problem avoiding. In contrast, the propeller tips of a conventional design spin at very high speeds, often over 100km/h, which causes serious problems with bird and bat strikes.