How does the wind turbine produce electricity?

1.The wind passes over the blades creating lift (just like an aircraft wing) which causes the rotor to turn.
2. The blades turn a low-speed shaft inside the nacelle: wind energy is converted into rotating, mechanical energy.
3. In most wind turbines, mechanical energy is channelled to a gearbox. The gears connect the low speed shaft of the rotor with a high speed shaft that drives the generator. Here the slow rotation speed of the blades is increased to the high speed of generator revolution (ratio: 1:100). Some wind turbines do not contain a gearbox and instead use a direct drive mechanism to produce power from the generator.
4. The rapidly spinning shaft drives the generator to produce electric energy.
5. Electricity from the generator (around 700 V) goes to a transformer which converts it to the right voltage for the distribution system (33,000 V).
6. The electricity is transmitted via the electricity network. The nacelle is rotated automatically to follow the changing direction of the wind so as much energy as possible is captured.
Wind turbines generate energy at wind speeds of 4-25 metres per second. When turbines are generating electricity, the rotor speed will be 9-19 revolutions per minute, depending on the wind speed and the turbine type. If the wind reaches speeds over 25 metres per second, which happens rarely, the wind turbine stops because such speeds place too much strain on the turbine’s components. In the early days of modern wind power, wind turbine rotors were 20 metres in diameter and had a capacity of 20-60 kW. Ten years later, the machines had a capacity of 500 kW, and today offshore turbines can reach up to 5 MW or more, spanning 120 metres – longer than a football field. The average size of onshore turbines being manufactured today is around 2.5-3 MW. One 2.5 MW onshore turbine produces power for over 1,500 EU households.The larger blade lengths capture more wind and therefore produce more electricity and reduce the cost of power generation.