Wind energy is the energy generated by the wind. Since ancient times, human beings have been exploiting the wind to sail and to move the mill vanes used to grind cereals, press olives or pump water. Wind energy have been used to produce electrical power only during the last decades. Modern windmills are called aerogenerators Aerogenerators’ working principle is the same that moves the windmills: it is the wind that pushes the blades. In the case of aerogenerators, the rotation movement of the blades is transmitted to a generator which creates electricity.

AEROGENERATORS

There are many kinds of aerogenerators, of different shapes and dimensions. They can have one, two or three blades of different length: aerogenerators with 50 cm blades are used as battery chargers, while those with 30 mt blades can produce an energy of 1,500 kW and can satisfy the daily electrical consumption of about 1,000 families. The most common aerogenerators are medium sized, more than 50 mt high and with two or three blades 20 mt long. This kind of aerogenerators can produce a power of 500-600 kW and satisfies the daily electrical needs of about 500 families.

WIND-FARMS
A group of interconnected aerogenerators forms the so-called "wind-farms", that are proper electrical power stations.