Windmill

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For other uses, see Windmill (disambiguation).

A Dutch tower windmill surrounded by tulips

A windmill is an engine powered by the wind to produce energy, often contained in a large building as in traditional post mills, smock mills and tower mills. The energy windmills produce can be used in many ways, traditionally for grinding grain or spices, pumping water, sawing wood or hammering seeds. Modern wind power machines are used for generating electricity and are more commonly called wind turbines.

1 History
2 Windpumps
3 Modern windmills
4 Cultural and literary influence
5 Footnotes
6 Further reading
7 See also
8 More images
9 External links
- 9.1 History links

[edit] History

A windwheel operating an organ is described as early as the 1st century AD by the Greek engineer Heron, marking probably the first instance of wind powering a machine in history.^[1] ^[2] Horizontal windmills were used in eastern Persia (Sistan) by the 9th century AD as described by Muslim geographers.^[3] Vertical windmills of the type generally used today were invented in Northwestern Europe in the 1180s.^[4]

[edit] Early history

The first windmills had long vertical shafts (also called 'horizontal windmill' due to the dimension of its movement) with rectangle shaped blades and appeared in Persia in the 9th century.^[3] The authenticity of an earlier anecdote of a windmill involving the second caliph Umar (634-644 AD) is questioned on the grounds of being a 10th century amendment.^[5] Made of six to twelve sails covered in reed matting or cloth, these windmills were used to grind corn or draw up water, they were quite different from the European versions. A similar type of vertical shaft windmill with rectangle blades, used for irrigation, can also be found in 13th century China.

[edit] Europe

Upminster (Essex, UK) Windmill in June 2006; a smock mill - before it lost one of its sails in an early 2007 storm.

In Europe, the vertical or horizontal-shaft windmill date from the last quarter of the 12th century in the triangle of northern France, eastern England and Flanders. These earliest mills were used to grind cereals. The evidence at present is that the earliest type was the post mill, so named because of the large upright post on which the mill's main structure (the "body" or "buck") is balanced. By mounting the body this way, the mill is able to rotate to face the (variable) wind direction. By the end of the thirteenth century the masonry tower mill, on which only the timber cap rotated rather than the whole body of the mill, had been introduced. Due to the fact that only the cap of the tower mill needed to be turned the main structure could be made far larger, enabling the sails to catch more wind and be made longer. Windmills were often built atop castle towers or city walls, and were a unique part of a number of fortifications in New France, such as at Fort Senneville.

The fantail, which automatically turns the heavy cap against the wind, was invented in England in 1745. The smock mill is a later variation of the tower mill, constructed of timber and originally developed in the sixteenth century for land drainage. With some subsequent development mills became versatile in windy regions for all kind of industry, most notably grain grinding mills, sawmills (late 16th century), threshing, and, by applying scoop wheels, Archimedes' screws, and piston pumps, pumping water either for land drainage or for water supply.

With the industrial revolution, the importance of windmills as primary industrial energy source was replaced by steam and internal combustion engines. Polder mills were replaced by steam, or diesel engines. The industrial revolution and increased use of Steam and later Diesel power however had a lesser effect on the Mills of the Norfolk Broads in the United Kingdom, these being so isolated (on extensive uninhabitable marshland), therefore some of these mills continued use as drainage pumps till as late as 1959. More recently historic windmills have been preserved for their historic value, in some cases as static exhibits where mearly machinery is too fragile to put in motion, and in others as fully working mills.

With increasing environmental concern, and approaching limits to fossil fuel consumption, wind power has regained interest as a renewable energy source. This new generation of wind mills produce electric power and are more generally referred to as wind turbines.

See Flood control in the Netherlands for use of windmills in land reclamation in the Netherlands.

[edit] In Canada and the United States

Farm windmill, Sheridan County, Kansas, USA, 1939.

Windmills feature uniquely in the history of New France, particularly in Canada, where they were used as strong points in fortifications.^[6] Prior to the 1690 Battle of Québec, the stong point of the city's landward defences was a windmill called Mont-Carmel, where a three-gun battery was in place.^[6] At Fort Senneville, a large stone windmill was built on a hill by late 1686, doubling as a watch tower.^[7] This windmill was like no other in New France, with thick walls, square loopholes for muskets, with machicolation at the top for pouring lethally hot liquids and rocks onto attackers.^[7] This helped make it the "most substantial castle-like fort" near Montréal.^[8]

In the United States, the development of the water-pumping windmill was the major factor in allowing the farming and ranching of vast areas of North America, which were otherwise devoid of readily accessible water. They contributed to the expansion of rail transport systems throughout the world, by pumping water from wells to supply the needs of the steam locomotives of those early times. They are still used today for the same purpose in some areas of the world where a connection to electric power lines is not a realistic option.

The multi-bladed wind turbine atop a lattice tower made of wood or steel was, for many years, a fixture of the landscape throughout rural America. These mills, made by a variety of manufacturers, featured a large number of blades so that they would turn slowly with considerable torque in low winds and be self regulating in high winds. A tower-top gearbox and crankshaft converted the rotary motion into reciprocating strokes carried downward through a rod to the pump cylinder below.

Windmills and related equipment are still manufactured and installed today on farms and ranches, usually in remote parts of the western United States where electric power is not readily available. The arrival of electricity in rural areas, brought by the Rural Electrification Administration (REA) in the 1930s through 1950s, contributed to the decline in the use of windmills in the US. Today, the increases in energy prices and the expense of replacing electric pumps has led to an increase in the repair, restoration and installation of new windmills.

[edit] Windpumps

Brograve Mill, UK. An example of the derelict state of many Broadland Windpumps

A windpump is a windmill used for pumping water from a well or draining land.

On US farms, particularly in the Midwest, windpumps of the type pictured were used to pump water from farm wells for cattle. Today this is is done primarily by electric pumps, and only a few windpumps survive as unused relics of a previous technology.

Windpumps similar in construction to the ones from the US Midwest are still being used extensively in Southern Africa. In South Africa and Namibia thousands of windpumps are still operating. These are mostly used to provide water for human use as well as drinking water for large sheep stocks. At least 21 different types of windpumps are still operational in South Africa^{[citation needed]}. Unfortunately few manufacturers still exist, although Southern Cross, Climax (Stewards and Lloyds) and Poldaw windpumps are still distributed^{[citation needed]}.

The Netherlands is well known for its windmills. These iconic structures situated along the edge of polders are actually windpumps, designed to drain the land. These are particularly important as much of the country lies below sea level.

Many windpumps were built in The Broads, of East Anglia in the United Kingdom for the draining of land. They have since been mostly replaced by electric power, many of these windpumps still remain, mainly in a derelict state, however some have been restored.

[edit] Modern windmills

Spanish windmills at La Mancha.

Main article: Wind turbine

Modern windmills are properly called wind turbines or wind generators, and are primarily used to generate electric power. Modern windmills are designed to convert the energy of the wind into electricity. About 2,000 large windmills can generate the same amount of power as a modern power station.

[edit] Cultural and literary influence

Miguel de Cervantes' book Don Quixote de La Mancha, - which helped cement the modern Spanish language and is regarded as one of the greatest works of fiction ever published ^[9] - features an iconic scene in which Don Quixote attacks windmills that he believes to be ferocious giants. This gave international fame to La Mancha and its windmills, and is the origin of the phrase "tilting at windmills", to describe an act of futility.

[edit] Footnotes

^ A.G. Drachmann, "Heron's Windmill", Centaurus, 7 (1961), pp. 145-151
^ Dietrich Lohrmann, "Von der östlichen zur westlichen Windmühle", Archiv für Kulturgeschichte, Vol. 77, Issue 1 (1995), pp.1-30 (10f.)
^ ^a ^b Ahmad al-Hassan, Donald Hill: Islamic Technology. An illustrated history, 1986, Cambridge University Press, p.54f. ISBN 0-521-42239-6
^ Dietrich Lohrmann, "Von der östlichen zur westlichen Windmühle", Archiv für Kulturgeschichte, Vol. 77, Issue 1 (1995), pp.1-30 (18ff.)
^ Dietrich Lohrmann, "Von der östlichen zur westlichen Windmühle", Archiv für Kulturgeschichte, Vol. 77, Issue 1 (1995), pp.1-30 (8)
^ ^a ^b Chartrand, French Fortresses in North America 1535–1763: Québec, Montréal, Louisbourg and New Orleans
^ ^a ^b Chartrand, p 41
^ Chartrand, p. 38
^ BBC.

[edit] Further reading

A.G. Drachmann: "Heron's Windmill," Centaurus, 7 (1961), pp. 145-151
Hugh Pembroke Vowles: "An Enquiry into Origins of the Windmill", Journal of the Newcomen Society, Vol. 11 (1930-31)

[edit] See also

[edit] More images

Muttons Mill, one of the many drainage windpumps on the Norfolk Broads (United Kingdom)	Pitstone Windmill, believed to be the oldest windmill in the British Isles	Windmills of Western Siberia, taken by Prokudin-Gorskii, c. 1910	Original seventeenth century wooden windmill, Gettlinge, Oland, Sweden.
The windmills of Kinderdijk, the Netherlands	Double windmill and common Aeromotor windmill in Texas	The middle-18th-century windmill of Nesebar, Bulgaria	Windmill near Tés
Weybourne Windmill, Norfolk, England	A Midwestern wind pump in Arlington, Indiana. The mechanism connecting the wheel to the pump is missing.	A modern windmill in Sweden.	A Windmill at the National Ranching Heritage Center
An antique functioning windmill and a cart for transporting water at the National Ranching Heritage Center	Modern wind turbine in Aalborg, Denmark

[edit] External links

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