In contrast to a fan that employs electricity to generate wind, a wind turbine consists of blades that are shaped in such a way that the wind forces them to rotate. As the blades circle, a low speed shaft with a gear begins to spin. This gear connects to another gear on a high speed shaft that is part of a generator.
Nestled within the generator, the high speed shaft contains a magnetic rotor that spins within copper wires coiled around a core of iron. This interaction produces voltage across the coils. The resulting current is then transformed for use in a power grid.
The design of modern wind turbines are either horizontal axis or vertical axis. Resembling traditional windmills, horizontal-axis wind turbines consist of two or three blades that face the wind. Vertical-axis wind turbines bear a likeness to an egg-beater.