Dutch windmill

The earth’s surface heats up to varying degrees, leading to the formation of air currents: the winds.

Like waterpower, windpower is a clean, inexhaustible source of energy. However, it can only be harnessed to a limited extent. The direction and strength of the winds change or the winds develop great destructive forces. Windpower began to be used for sailing over 5000 years ago. Windmills have been found in Persia dating back to the 7th century. From the 11th century onwards the windwheels spread from the coasts throughout Europe.

A horizontal wheel with a vertical shaft was typical of oriental windmills. In contrast, European wheels ran vertically and turned a horizontal shaft. The more efficient vertical wheel spread throughout the world. Windwheels provide the energy to drive mills of various kinds, irrigation and drainage systems, hammer, stamping and milling works, electric generators.

High-speed wind turbines with aerodynamically shaped vanes began to be developed about 50 years ago. These work more efficiently than the traditional, slow-moving windwheels.

The development of wind turbines has by no means come to an end. Research projects with wind-driven plants of differing power are being carried out throughout the world.