How do wind power plants work?

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In line with windmills, wind turbines, (also called wind generators) use the power of the wind which they turn into electricity. The speed of the wind turns the blades of a rotor (between 10 and 25 turns per minute), a source of mechanical energy. The rotor then turns a generator which transforms the mechanical energy into electricity. An electric motor orientates the nacelle so that its rotor is positioned facing into the wind. Each turbine is made up of a mast of between 20 and 100 m according to the power of the machines. The mast supports the rotor, usually equipped with three blades, and the nacelle which contains the generator and electrical and mechanical back-up.

The power of modern turbines is over 3 MW on land. Wind turbines are designed for wind speeds of between 14 and 90 km/h. Above that, a braking mechanism automatically stops the turbine for the safety of the equipment and to minimise wear and tear. Modern wind turbines supply their nominal power at around 50 km/h.

How are wind turbines connected to the electricity network ?

Wind turbines are connected to the electricity network via a transformer located at the base of the mast. The electricity produced is generally stepped up to the voltage of the network (20 kV), then it passes through a delivery substation before being fed into the distribution or electrical transport network.

The acoustic dimension in wind farm projects

Acoustic dimension in wind farm

Noise perception generated by the wind turbines (comparison). For a household at the minimum authorized distances of 500m, a wind turbine emits the same noise as a washing machine (40dB).

 

Sound emitted by a turbine spreads in every direction. Topography, cloud cover or the nature of the air masses, may play a part in its spread. ENGIE applies the acoustic standards applicable to onshore wind power plants, within the framework of the system for installations classified for environmental protection (ICPE).

 

Doubling the number of wind turbines

 

Doubling the number of wind turbines does not double the volume of sound. From a distance of one kilometre, it only adds 3 dB. The total sound level of a wind farm is limited to 70 dB(A) during the day and 60 dB(A) at night over a distance of 200 metres).