Wind energy technology

Worldwide, wind farms are starting to appear throughout the country side and help with the daily production of energy.

The principle of wind energy:

The wind vane (2) transmits the direction of the wind to the automatic control system (1).  When it reaches a sufficient speed, the yaw motors (3) then position the turbine in the direction of the wind, allowing the blades to rotate (4). The movement of the blades is transmitted to the slow shaft (5), then to the gearbox (6), the quick shaft (7) and, lastly, the generator (8).

1 Automatic control system
2 Wind vane
3 Yaw motor
4 Blades
5 Slow shaft
6 Gearbox
7 Quick shaft
8 Generator
9 Hydraulic Units
10 Bearings
11 Disk break

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For the wind turbine to be able to produce electricity, the wind speed must reach at least 15 km/h. The generator delivers an alternating current at 690 volts.

The wind turbine reaches its optimal capacity at a wind speed of 50 km/h. The hydraulic unit (9) regulates the lift on the blades, pivoting them on their bearings (10), thus ensuring constant power.

Over 90 kmph, the blades are “feathered”, i.e. positioned parallel to the wind. The generator is disconnected from the network. The wind generator will only resume its production within the band of wind speed permits.

A computer manages all these operations automatically and, if necessary, a disk break (11) makes an emergency stop.

The 690 volts are converted into 20,000 volts by a transformer positioned at the foot of each wind generator or in the tower. The electricity produced is then transported underground towards source electrical substations so that it can be distributed to consumers.

Environmental impact

This technology doesn’t create any greenhouse gas or waste that requires treatment. Wind energy also guarantees the integrity of sites after they are dismantled. In terms of acoustics, depending on the topography and the distance from homes, a new-generation wind turbine is barely audible with a sound level of less than 40 db at 300 metres, that is, the equivalent to the noise from a quiet conversation.

The impact on the landscape is a matter of personal opinion. Beautiful and elegant for some, an eyesore for others.

The type of wind turbine
• Mast height: 125 metres
• Blade length: between 20 and 55 m
• Wind turbine capacity: between 0.6 MW and 3 MW – up to 5 MW for offshore wind turbines.

By way of example, 1 MW corresponds to the domestic electricity needs, excluding heating, of 1,000 homes.

A 10 MW wind farm responds to the needs of around 10,000 homes, that is around 25,000 people.

 

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