Winds are caused by uneven heating of the atmosphere by the sun, the roughness of the Earth surface and Earth’s rotation. Winds flow patterns are changed by the topography of land, water and plants. Modern wind turbines use this flow of air to generate electricity. Humans use this wind flow for various purposes e.g.: generating electricity, drying clothes, sailing.
The fact that wind energy is most widely available, abundant and increasingly cost-competitive energy resources, making it a viable alternative to fossil fuels that harm our health and threaten the environment .
How fast the wind blows, how often and when has an important role to play in power generation costs. Power output of wind turbines increases as the cube of wind speed.
In other words, if the speed of the wind doubles, the production of electricity is increased about eight times. Thus, the winds with the higher speed are less expensive and easier to catch.
The term wind power describes the process by which wind is used to make the mechanical energy or electricity. Wind turbines convert the kinetic energy of wind energy into mechanical power.
This mechanical power may be used for certain activities (such as milling of rice or pumping water) or a generator can convert mechanical energy to electrical energy at home, business, schools and other facilities.
Most wind turbines turn in the moving air like blades of propeller aircraft and supply power to an electric generator that produces electricity. Wind turbines, rather than working as a fan in your house that uses electricity to generate wind, use wind power to generate electricity.
The wind turns the blades, which spin a shaft connected to the generator and produces electricity. Turbine blades are designed in such a way that wind causes them to rotate, which rotates the shaft at low speed, with a gear at the end that itself is connected to small gear on high speed shaft that runs through alternator housing.
The generator produces electricity using the same principle as a generator of your car (depending on the turbine). Magnetic Rotor inside the generator on high speed shaft spins inside loops of copper wire that are wound around an iron core. The rotor creates “electromagnetic induction” as it spins around the inside of the core through the coils, which generates electrical power. The current is regulated and transmission network (or home network system connection), after some changes, so it can use in our homes or sent to a battery bank for storage.
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.
Wind turbines which are a part of renewable energy has been playing significant role in reducing our dependency on fossil fuels by offering some great solutions to generate electricity, currently represents over 10% of electricity in some countries.
Scientists predict that this percentage will increase in the coming years as more and more countries will allocate part of their budget in increasing their reliance on these renewable energy sources thereby reducing pollution levels and global warming. This is all part of the fight to reduce global warming induced climate change and reduce our dependence on fossil fuels.