WIND POWER

The Wind energy is the energy generated by the wind and can be used directly or be transformed as electric power. You can apply this energy on a large scale, being one of the most productive renewable energies or in small installations. It is currently the fastest growing renewable energy and represents a large portion of the electricity production. This kind of has a lot of potential and a great number of applications. The installation of an aerogenerator in a windy region, allows the production of electricity for a remote home, to pump water, or for any other isolated application for which electricity is needed.

We owe the first electricity generating wind turbine to Charles F. Brush (1849-1929), one of the founders of the American electric industry. It was a giant of 144 blades made out of cedar wood. It functioned for 20 years and charged the batteries in the basement of his mansion. In the 50´s the first alternating current turbines were developed. The first oil crisis (1973) generated a real interest in wind energy. The generation of wind turbines of 55 kW of 1980, represented the technological and industrial boom for the modern aerogenerators.

This energy consists of generating electricity by means of wind mills that move a turbine. The aerogenerator, normally, has three blades connected to a rotor that activates an electric generator. That´s what we see placed at the top of the mast of a typical aerogenerator. It is achieved through the kinetic energy produced by this movement. When the wind blows at double speed, eight times more energy is generated. The power of the generator is in function to the length of its blades, the greater the length, the greater power is obtained and consequently, more electricity is generated.

This kind of energy seems to be the one that has the most future of all the renewable energies, along with solar energy. It can be used, like solar power, to generate electricity in remote areas, where connections to the power grid do not exist or it can be sold to the electric company. Just like the photovoltaic system it is the most simple and economic way to get water to farm lands isolated from the electric grid, using the most appropriate technology for agricultural development.

The size of the aerogenerators can vary, from units that start at 400w and blades with a diameter of 3 m. to commercial aerogenerators installed by large companies that reach 2.5MW of power and blades of 80m in diameter. Every aerogenerator needs a minimum starting speed, which is 11km/h for this type. It´s biggest productivity is with winds around 45km/h, but if the wind reaches 100km/h, they stop running automatically, to avoid damaging the unit

The use of this type of energy is only applicable in very windy areas, with wind almost every day of the year and an average wind speed of above the fore mentioned of 11km/h, as the minimum for the aerogenerator to start working.

It´s quite common to combine this type of energy with photovoltaic solar energy, since the necessary weather conditions for both technologies are complementary. Sun and wind, together, are not usually combined very often.

We can emphasize that wind energy is generated indirectly thanks to the Sun. The sun heats the air and this causes the currents that generate wind. Wind is inexhaustible, and is renewed on a continuous basis. Winds are therefore variable, and so is wind energy production.

The wind power  is becoming increasingly less expensive, as the technology advances. It allows progress without hurting the Earth, respecting the environment. It does not cause any type of contamination. It can be obtained, in greater o smaller degree, everywhere.