Wind energy is the energy obtained from wind, i.e. the kinetic energy generated by the effect of air currents, and is transformed into other useful forms of human activities.
The term wind comes from the Latin aeolicus belonging or relating to Aeolus, god of the winds in Greek mythology. Wind energy has been used since ancient times to move boats powered by sail or operate machinery mills moving blades.
Today, wind energy is mainly used to produce electricity using wind turbines. At the end of 2007, worldwide capacity of wind generators was 94.1 gigawatts. In 2009, wind generated approximately 2% of global electricity consumption, equivalent to the total demand for electricity in Italy, the world’s seventh largest economy. In Spain wind energy produced 11% of electricity consumption in 2008, three in April and 13.8% in 2009. On the morning of Sunday November 8 of 2009, over 50% of the electricity produced in Spain generated the windmills, and the record-breaking total production, with 11,546 megawatt turbines.
Wind energy is an abundant, renewable, and clean and helps reduce emissions of greenhouse gases by replacing power plants based on fossil fuels, making it a kind of green energy. However, the main drawback is its intermittency.
How To Produce And Use Wind Energy
Wind energy is related to the movement of air masses move from areas of high atmospheric pressure to adjacent areas of low pressure, with velocities proportional to the pressure gradient.
The winds are generated because of the uneven heating of the Earth’s surface by solar radiation, between 1 and 2% of energy from the sun becomes wind. By day, the air masses over the oceans, seas and lakes remain cool compared to neighboring areas located on the masses.
The continents absorb less sunlight, so the air is on the ground expands and therefore becomes lighter and rises. Cooler air and heavier than comes from the seas, oceans and large lakes is set in motion to fill the void left by the hot air.
To take advantage of wind energy is important to know the diurnal and nocturnal and seasonal winds, changes in wind speed with height above the ground, the entity of the bursts in short periods of time, and maximum values occurred in historical data with a minimum of 20 years. It is also important to know the maximum wind speed. To use wind power, you need it reaches a minimum speed that depends on the wind turbine to be used but usually begin between 3 m / s (10 km / h) and 4 m / s (14, 4 km / h), speed-called ” cut-in speed “and not exceeding 25 m / s (90 km / h), speed-called” cut-out speed . “
Wind energy is used through the use of wind machines (or windmills) can transform wind energy into usable mechanical energy of rotation, either to directly drive the operating machines, and for the production of electricity. In the latter case, the conversion system (which includes an electric generator with its control systems and connection to the network) is known as wind turbines.
It is now primarily used to move turbines. These wind drives a propeller through a mechanical system rotates the rotor of a generator, usually a generator that produces electricity. For installation profitable are often grouped together in concentrations called wind farms…
A mill is a machine that converts wind into usable energy that comes from the action of the wind on a slanted blades attached to a common axis. The rotary axis can be connected to various types of machinery to grind grain, pump water or generate electricity. When the shaft is connected to a load such as a pump, called the Windmill. If used to produce electricity is called a wind turbine generator. The mills have a remote source.
Wind power is not new, is one of the oldest energy with thermal energy. Since the book Don Quixote, windmills were present, perhaps the world’s most famous windmills. “The venture is guiding our affairs better than acertaramos to wish, for you see there, friend Sancho Panza, where thirty or discover a few more monstrous giants whom I mean to fight and remove all the lives (…). -Look, your worship, replied Sancho, which those who appear there are not giants but windmills, and what they look like arms are the vanes that turned by the wind make the millstone go. “
The wind as a driving force existed since ancient times and in all times has been used as such, as we observe. It originates from the sun. Thus, it has moved to boats powered by sail or machinery has operated the mill moving blades. But it was not until the eighties of last century when this type of clean energy suffered a real boost. Wind power is growing inexorably from the XXI century, in some countries than others, but certainly in Spain there is a lot of growth, one of the first countries behind Germany in Europe or the United States to worldwide. Its boom in wind farms is due to the conditions so favorable that there is wind; especially in Andalusia occupies a leading place among those who can point to the Gulf of Cadiz, as the wind resource is exceptional.
The earliest reference we have is a windmill that was used to power an organ in the first century CE. The first practical use mills were built in Sistan, Afghanistan, in the seventh century. These were vertical axle windmills of rectangular sheets. Devices made 6 to 8 mill sails covered in fabric were used to grind corn or pump water.
In Europe the first windmills appeared in the twelfth century in France and England and is distributed across the continent. They were wooden structures, known as windmill towers, which were rotated by hand around a central pole to lift the sails to the wind. The tower mill was developed in France during the fourteenth century. It consisted of a stone tower topped by a wooden structure that supported rotating shaft and the machinery of the mill top of it. These first units had a number of common characteristics. This axis departed from four to eight blades with a length between 3 and 9 meters. The wooden beams were covered with cloth or wood. The energy generated by the rotation of the shaft is transmitted through a gear system, the machinery of the mill located at the base of the structure. The horizontal axis windmills were used extensively in Western Europe to grind wheat from the 1180s onwards. Just remember the now famous windmills in the adventures of Don Quixote. There are still mills that class, for example, in the Netherlands.
In the U.S., the development of pumping windmills, recognizable by their multiple candles metal was the main factor that allowed agriculture and livestock over vast areas of North America, otherwise impossible without easy access to water. The mills contributed to the expansion of the railway around the world, supplying the water needs of the steam locomotives.
Modern turbines were developed in early 1980, although the designs continue to evolve.
Use of wind energy
The wind energy industry in modern times began in 1979 with mass production of wind turbines by Kuriant manufacturers, Vestas, Nordtank and Bonus. Those turbines were small by today’s standards, with capacities from 20 to 30 kW each. Since then, the size of the turbines has grown enormously, and production has expanded too many countries.