A single MW of power generated by harnessing wind can be used to power somewhere around 250-300 American households. As of 2010, the worldwide installed capacity of wind-powered generators - i.e. intended technical full-load sustained output of these generators, stands at 175 GW (1 gigawatt = 1000 megawatts). At 340 TWh, the total amount of electricity attributed to wind power was 2 percent of the world power usage in 2009. We have come a long way from the use of kinetic energy of wind to propel boats to conversion of this energy into mechanical energy and using it for electricity production.
History and Timeline of Wind Power
Even though it's a normal human tendency to associate wind energy conversion with generation of electricity, the history of harnessing wind power can be actually traced back to antiquity - wherein it was used to propel boats in the Middle East. Back then, water transportation was by far the most important mode of transportation, and historical accounts suggest that the Egyptians were the first to use wind power to propel their boats along river Nile way back in 5000 BCE. Even though attempts to harness wind energy to power other modes of transportation were also made, none of them even came close to the success of its use for marine transportation.
From Sail Boats to Windmills
While the use of wind power to facilitate water transportation spread to other parts of the world with European nations using it to power their fleet of ships, new methods of harnessing wind energy i.e. the kinetic energy of wind to be precise, were introduced in various parts of the world. In fact, the first windmill - developed in Sistan (the border region of eastern Iran) was based on the very principle of wind power propulsion.
Referred to as the panemone windmill, it was a vertical-axis windmill which had some vertically placed drive shafts with reed matting on board. This windmill was used for grinding corn and pumping water for agricultural purpose in this region.
In the beginning of the 12th century, horizontal-axis windmills - known as the sunk post mills, were introduced in northern Europe wherein they were predominantly used for grinding corn. The horizontal-axis windmills of Europe differed from their vertical-axis counterparts of Middle East in context of design. In these windmills, the broad house-shaped body or tower housed the equipment which was required for grinding corn.
One of the best documented use of such windmills was its use by the Dutch to drain lakes and marshes in the Rhine River Delta back in the 14th century. Roughly during the same period, these windmills were used to pump water from the sea for salt production in Italy, China, Bermuda, etc.
From Windmills to Wind Turbines
Even though the term windmill is often used to refer to wind powered generators, technically it refers to a mill that is powered by wind, while the wind powered generators are referred to as wind turbines. The use of windmills was at its peak between the 18th-19th century, with their upgraded versions - the wind turbines, being used for electricity generation for the first time by Prof James Blyth in Scotland in July 1887. Blyth used his 33-foot wind turbine to power his cottage in Kincardineshire county in northeast Scotland.
In the United States, windmills were first used to pump water on farms and ranches, and wind turbines to generate electricity. By the beginning of the 19th century, there were millions of small windmills operating in the United States, a trend which was attributed to the fact that several leading companies entering the market as windmill suppliers for home use.
Recent Developments in Wind Power Generation
Towering at 60 ft, the first large wind turbine dedicated to electricity generation was built by Charles F. Brush in Cleveland, Ohio, in 1887. The wind turbine built by Dane Poul La Cour in 1891 became the first wind turbine to incorporate the aerodynamic design principle. Given below is a compilation of more of such milestones in the history of wind power generation.
- In 1920s, the first vertical-axis wind turbine - resembling an eggbeater, was built by Frenchman George Darrieus.
- The first major wind turbine which boasted of a potential of 32 percent and the ability to generate 100kW power was built in Yalta, USSR, in 1931.
- The first wind turbine to generate power in terms of megawatt (MW) was built in Vermont in 1941.
- In 1956, Johannes Juuls built the Gedser wind turbine which was equipped with the emergency aerodynamic tip break which is widely used even today.
- In 1970s, the US government began its research on the feasibility of wind power generation.
- In 1980, the first wind farm of the world - with a total of 20 wind turbines, was built in New Hampshire, US.
- The first off shore wind farm with a total of 11 wind turbines was built in Vindeby, Denmark, in 1991.
The use of wind power for electricity generation has increased by a significant extent in course of time. In 2009, the 71 billion kW-hrs of power produced by wind turbines in the United States served 6.4 million American households. As of 2009, 80 nations resort to wind power use on a commercial basis, and that in itself speaks in volumes about the soaring popularity of this alternative source of power.
If we go by belief that development and controversies go side by side, wind power will be undoubtedly the best example of the same. While its supporters are trying their level best to put forth wind energy as the source of energy for our future, critics of the same have been coming up with several loopholes in the same. Whilst going through wind energy pros and cons, you can't help, but notice that we still need to put in efforts to multiply its positive attributes and minus its disadvantages to ensure that wind energy makes a strong case when pitted against other alternative sources of power.