Transmissions have so far been one of the main causes of downtime. They are subject to particularly high wear and can fail after just ten years. The trend is therefore towards optimized transmissions, lower gear ratios, and even to gearless drives. The latter leads to a short construction design with just one main bearing.
The slowly rotating rotor blades drive the generator directly, meaning the speed remains constant, but the torque that occurs over the entire drive train is then very high.
The advantage of missing the transmission is acquired by the use of multipolar generators with permanent magnets, which in turn contain expensive, rare earths – another reason to increase the service life of the plants in order to minimize costs.