Energy

A bit of history

Man learned how to use the kinetic energy of the wind thousands of years ago. Sailing dates back to at least 10,000 years ago. The first wind mills of which rests were found were Persian and date back to 200 B.C. They were built in a very simple way, with sails mounted on wooden frames. During the following centuries, windmills became common all over the Middle East and became a commonly used machine in the agricultural sector. Then, between 1200 and 1300 they reached Europe, especially the northern countries. Leonardo da Vinci himself contributed to the evolution of such machines. More sophisticated technologies were introduced around 1600: the shape of the vanes was improved, and the vanes were streamlined to exploit the wind strength better. In the Encyclopedie by Diderot and D’Alambert, written towards the end of the 1700s, contains a picture of them. At that time wind power was not exploited to grind cereals but rather to reclaim flooded land. The invention of the dynamo by the Belgian Gramme in the mid-twentieth century opened up new horizons to the use of water- and wind-energy, and in 1887 the French Duc de La Peltrie built the first aerogenerator in Europe for the production of power: the exploitation of wind energy for the industry was born. In the same period, the United States produced the first “windmill” for the production of electricity (Charles Brush, Ohio, 1890). The production of electric power from wind energy developed between 1920 and 1930, after the creation of turbines for the processing of hydraulic energy After a period of oblivion, the oil crisis of 1973 led to a revival of the interest in renewable energy sources, including wind power, which in certain cases is competitive against fossil fuels. Modern mills are faster and more efficient than at the beginning of the 20th century. They have fewer blades and can reach a speed up to five time great than that of the wind, with an energy output doubled as compared to traditional wind mills.