/WIND TECHNOLOGY
/WIND TURBINES
How do wind turbines work?
The wind’s kinetic energy is transformed into electricity by wind turbines. These are made up of a tower and a gondola comprising a rotor and measurement apparatus (an anemometer to measure wind speed, a weather vane or “weather cock” to indicate wind directions and a lightning conductor).
The rotor is composed of the blades and an axle, attached to each other by a bearing. The blades are moved by the wind and transmit this force to the bearing, which is connected to a multiplier that increases the axle speed. The mechanical energy is transferred from the multiplier to an electricity generator, which transforms it into electricity for subsequent injection into the grid.
There are two most common types of wind turbine, depending on the position of the axle around which the blades rotate: vertical- or horizontal-axle. Horizontal-axle wind turbines are more developed in both technical and commercial terms. These are the best suited for large-scale generation of electricity. The most commonly used number of blades is three, since this number provides the best efficiency to lowest air resistance relationship. The range of wind turbine power goes from 100 W (blade diameter of around 1 metre) to about 5 MW (blade diameter and tower height greater than 100 metres).