Monday, March 15, 2010
Wind Turbines: Harnessing the Wind for Electricity
As early as the 1930's, wind was used to generate electricity in rural farming areas, mostly where electric distribution systems had not yet been installed. Now we have gone full-circle with modern, “personal use” wind turbines designed to produce electricity in homes when the wind is blowing.
Systems are now available that can either store electricity or, depending on the utility company, can spin the meter backwards, sending electricity back to the grid, giving credit to the wind machine owner. When the wind is not blowing, the house is powered by the utility.
Wind turbines can also be used on a larger scale to power neighborhoods, businesses and schools. Large turbines are grouped together into “wind farms,” which provide bulk power to the electrical grid.
When mechanical energy is used directly by machinery, such as a pump used to lift water from underground, the machine is usually called a windmill. A wind turbine is a machine for converting the kinetic (motion) energy in wind into mechanical energy.
If the mechanical energy is then converted to electricity, the machine is called a wind generator.
The two types of wind turbines, based on the axis on which the turbine rotates, are horizontal axis and vertical axis. The most common, horizontal-axis wind turbines, typically have either two or three blades which operate with the blades facing into the wind. Vertical-axis turbines have the motor shaft running vertically to the ground and usually result in lower energy extraction efficiency.
Wind turbines are also classified by the location in which they are used: onshore, offshore or aerial, and each have unique design characteristics. Wind turbines may also be used in conjunction with a solar collector to extract the energy of the sun.
Not all opinions are positive regarding wind turbines, however. Noise and vibrations from the rotating blades may interfere with the tranquility of some nearby country dwellers. In Kansas, many object to the interrupted land aesthetics converting wild prairies into vast industrial areas. Radio, TV, wireless Internet, phone, anything that receives or transmits over the airways may, in some areas, be affected by wind turbines. As a result of these problems, property values could be impacted.
Putting the wind to work is not a new concept and the use of wind turbines has caused problems for some. Corralling wind power for efficient, safe use has a way to go toward perfection. But we’re getting closer to efficiently utilizing the wind’s unlimited potential.