Wind turbines, like aircraft propeller blades, turn in the moving air and power an electric generator that supplies an electric current. Simply stated, a wind turbine is the opposite of a fan. Instead of using electricity to make wind, like a fan, wind turbines use wind to make electricity. The wind turns the blades, which spin a shaft, which connects to a generator and makes electricity.
Wind Turbine Types
Modern wind turbines fall into two basic groups; the horizontal-axis variety, like the traditional farm windmills used for pumping water, and the vertical-axis design, like the eggbeater-style Darrieus model, named after its French inventor. Most large modern wind turbines are horizontal-axis turbines.
Horizontal turbine components include:
blade or rotor, which converts the energy in the wind to rotational shaft energy;
a drive train, usually including a gearbox and a generator;
a tower that supports the rotor and drive train; and
other equipment, including controls, electrical cables, ground support equipment, and interconnection equipment.
Power generation from wind has emerged as one of the most successful programmes in the renewable energy sector, and has started making meaningful contributions to the overall power requirements of some Countries. Wind turbines today are up to the task of producing serious amounts of electricity. Turbines vary in size from small 200W mini home turbines to structures to large machines rated at 2 MW or more.
Energy is a major input for overall socio-economic development. Use of fossil fuels is expected to fuel the economic development process of a majority of the world population during the next two decades. However, at some time during the period 2020-2050, fossil fuels are likely to reach their maximum potential, and their price will become higher than other renewable energy options on account of increasingly constrained production and availability. Therefore, renewables are expected to play a key role in accelerating development and sustainable growth in the second half of the next century, accounting then to 50 to 60% of the total global energy supply.