Wind Altas of Spain Approximately 2 % of the energy coming from the sun is transformed into the kinetic energy of the atmospheric winds. 35% of this energy gets dissipated into the atmosphere layer, only one kilometre above the ground. It is estimated that the rest, given its randomness and dispersion, could only be used by a thirteenth part of it, the necessary amount to supply 10 times the current primary energy amount in the world; hence, its enormous potential and interest.
Today, the usual way of taking advantage of the wind is through horizontal-axis wind generators. Every wind generator basically consists in a winward rotor, equipped with three streamline-design blades, which captures the wind energy and transforms it into mechanical rotation energy. The rotation movement is driven along an axis and in several multiplier stages to a generator – usually synchronous or double-fed asynchronous – whose function is to produce electric power. The mentioned items are placed on a gondola or frame supported, in time, by a tower or shaft.
Wind farms, either on land or at sea, are made up by a series of wind generators that collect the wind kinetic energy to transform it into electric power. The electric power produced by each of the wind generators, usually at medium voltage, is transported underground to a processing station which increases its voltage and then, it is fed into the distribution or transport grid along an output feeder line to the outlet agreed on.
Wind generators are usually arranged in rows, perpendicularly to the wind direction, with a separation of a three rotor-diameter span between one another. This separation tries to prevent that the turbulence caused by every machine in the wind may affect the rest of the wind generators. Precisely because of this, the separation between parallel rows is larger than a seven rotor-diameter span.
Surely, there are other wind turbines: if focussing on their typology: vertical axis, two-blade, multiblade, winward-rotor wind turbines. And if focussing on their size: from small wind generators, less than one-metre diameter and capacities less than 1 kilowatt, to huge machines over 100 metres in diameter and over 5,000 kW of nominal capacity. Some are found hinterland; others on the coast or in deep sea.
They are used to generate large-scale electric power or to provide isolated houses with electric supply; to pump water or in the near future, to generate hydrogen or desalinate sea water.
Sotavento Experimental Wind Farm (A Coruña): You can find more information about the Sotavento Experimental Wind Farm from its website.