Brief History of Wind Energy
The energy of the wind has been harnessed since early recorded history all across the world. There are certain proofs that wind energy propelled boats along the river Nile around 5000 B.C. The use of wind to provide mechanical power came somewhat later in antiquity - by 200 B.C. simple windmills started pumping water in China, and vertical-axis windmills with woven reed sails were grinding grain in the Middle East. The Europeans got the idea of using wind power from Persians who introduced it into the Roman Empire by 250 A.D. However, the first practical windmills were made in Afghanistan around 7th century of our era. Since then, technology has been improving so by the end of 11th century people in the Middle East were using windmills extensively for food production. Returning merchants and crusaders carried this idea back to Europe where the Dutch refined the windmill and adapted it for draining lakes and marshes in 1300's.
In the late 19th century settlers in America began using windmills to pump water for farms and ranches, and later, to generate electricity for homes and industry (espacially in rural and desert areas). It is not hard to imagine how industrialization influenced the windmill businness later on. It led to a gradual decline in the use of it. However, the larger windmills generating electricity appeared. The first one was built in Scotland in 1887 by prof. James Blyth from Glasgow. Blyth's 33 foot high, cloth-sailed wind turbine was installed in the garden of his holiday cottage and was used to charge accumulators that powered the lighting in the cottage, thus making it the first house in the world to have its wind power supplied electricity. At the same time across the Atlantic, in Cleveland, Ohio, a larger and heavily engineered machine was constructed in 1888 by Charles F. Brush. His wind turbine had a rotor 17 meters in diameter and was mounted on a 18 meter tower. Although relatively large, the machine was only rated at 12 kW. The connected dynamo was able to charge a bank of batteries or to operate up to 100 incandescent light bulbs, three arc lamps, and various motors in Brush's laboratory. The machine fell into disuse after 1900. In the 1940's the largest wind turbine of the time began operating on a Vermont hilltop known as Grandpa's Knob. This turbine, rated at 1.25 megawatts in winds of about 30 m/h, fed electric power to the local utility network for several months during World War II.
In Denmark wind power has played an important role since the first quarter of the 20th century, partly because of Poul la Cour who constructed wind turbines. In 1956 a 24 m diameter wind turbine has been installed at Gedser, where it ran until 1967. This was a three-bladed, horizontal-axis, upwind, stall-regulated turbine similar to those used nowadays for commercial wind energy development. The popularity of using the wind energy has always fluctuated with the price of fossil fuels. When fuel prices fell in late 1940's, interest in wind turbines decreased . But when the price of oil skyrocketed in the 1970's, so did worldwide interest in wind turbine generators. Many wind farms and wind power plants have been built since then, and now wind energy seems to be the world's fastest-growing energy source that will power our industry as well as homes with clean, renewable electricity, according to scientists expectations.