windmill

The simple wind pump is an example of intermediate technology if it utilizes local materials and traditional design. In this way, there is no need for complex maintenance and repair, nor expensive spare parts.

An old tower windmill in Skagen, at the northernmost tip of the Danish mainland. The tower windmill was first used in Europe in the 14th century, for grinding grain and pumping water for irrigation.

Control arms of a tower windmill. The turret at the top of the windmill revolves so that the sails can be pointed into the prevailing wind. The sails turn a mill for grinding corn or pumping water.

Oland island in southern Sweden has many wooden windmills constructed in a style typical to the region. This example has been rebuilt at the Skansen Museum in Stockholm.

Mill with sails or vanes that, by the action of wind upon them, drive machinery for grinding corn or pumping water, for example. Wind turbines, designed to use wind power on a large scale, usually have a propeller-type rotor mounted on a tall shell tower. The turbine drives a generator for producing electricity.

Windmills were used in the East in ancient times, and in Europe they were first used in Germany and the Netherlands in the 12th century. The main types of traditional windmill are the post mill, which is turned around a post when the direction of the wind changes, and the tower mill, which has a revolving turret on top. It usually has a device (fantail) that keeps the sails pointing into the wind. In the USA windmills were used by the colonists and later a light type, with steel sails supported on a long steel girder shaft, was introduced for use on farms.