windmill

(wĭnd'mĭl')

1. A machine that runs on the energy generated by a wheel of adjustable blades or slats rotated by the wind.
2. Something, such as a toy pinwheel, that is similar to a windmill in appearance or operation.

tilt at windmills

1. To confront and engage in conflict with an imagined opponent or threat.

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Background

A windmill is a structure or machine that converts wind into usable energy through the rotation of a wheel made up of adjustable blades. Traditionally, the energy generated by a windmill has been used to grind grain into flour. Windmills are designed by skilled craftsmen and can be constructed on site using hand tools. Windmills developed steadily over the centuries and achieved their most prominence in Europe during the eighteenth century. They were largely replaced as a power generating structure when steam power was harnessed during the nineteenth century. Today, windmill technology is experiencing a renaissance and the wind turbine promises to be an important alternative to fossil fuels in the future.

History

Man has used wind to power machines for centuries. The earliest use was most likely as a power source for sail boats, propelling them across the water. The exact date that people constructed windmills specifically for doing work is unknown, but the first recorded windmill design originated in Persia around A.D. 500-900. This machine was originally used for pumping water then it was adapted for grinding grain. It had vertical sails made from bundles of lightweight wood attached to a vertical shaft by horizontal struts. The design, known as the panemone, is one of the least efficient windmill structures invented. It should be noted that windmills may have been used in China over 2,000 years ago making it the actual birthplace for vertical-axis windmills. However, the earliest recorded use found by archeologists in China is A.D. 1219.

The concept of the windmill spread to Europe after the Crusades. The earliest European designs, documented in A.D. 1270, had horizontal axes instead of vertical ones. The reason for this discrepancy is unknown, but it is likely a result of two factors. First, the European windmills may have been patterned after water wheels that had a horizontal axis. The water wheel had been known in Europe for long before this. Second, the horizontal axis design was more efficient and worked better. In general, these mills had four blades mounted on a central post. They had a cog and ring gear that translated the horizontal motion of the central shaft into vertical motion for the grindstone or wheel which would then be used for pumping water or grinding grain.

The European millwrights improved windmill technology immensely over the centuries. Most of the innovation came from the Dutch and the English. One of the most important improvements was the introduction of the tower mill. This design allowed for the mill's blades to be moved into the wind as required and the main body to be permanently fixed in place. The Dutch created multi-story towers where mill operators could work and also live. The English introduced a number of automatic controls that made windmills more efficient.

During the pre-industrial world, windmills were the electric motors of Europe. In addition to water pumping and grain grinding, they were used for powering saw mills and processing spices, dyes, and tobacco. However, the development of steam power during the nineteenth century, and the uncertain nature of windmill power resulted in a steady decline of the use of large windmill structures. Today, only a small fraction of the windmills that used to power the world are still standing.

Even as larger windmills were abandoned, smaller fan-type windmills were thriving. These windmills were used primarily for pumping water on farms. In America, these designs were perfected during the nineteenth century. The Halladay windmill was introduced in 1854 followed by the Aermotor and Dempster designs. The later two designs are still in use today. In fact, between 1850 and 1970 in the United States over six million were constructed.

Design

There are two classes of windmill, horizontal axis and vertical axis. The vertical axis design was popular during the early development of the windmill. However, its inefficiency of operation led to the development of the numerous horizontal axis designs.

Of the horizontal axes versions, there are a variety of these including the post mill, smock mill, tower mill, and the fan mill. The earliest design is the post mill. It is named for the large, upright post to which the body of the mill is balanced. This design gives flexibility to the mill operator because the windmill can be turned to catch the most wind depending on the direction it is blowing. To keep the post stable a support structure is built around it. Typically, this structure is elevated off the ground with brick or stone to prevent rotting.

The post mill has four blades mounted on a central post. The horizontal shaft of the blades is connected to a large break wheel. The break wheel interacts with a gear system, called the wallower, which rotates a central, vertical shaft. This motion can then be used to power water pumping or grain grinding activities.

The smock mill is similar to the post mill but has included some significant improvements. The name is derived from the fact that the body looks vaguely like a dress or smock as they were called. One advantage is the fact that only the top of the mill is moveable. This allows the main body structure to be more permanent while the rest could be adjusted to collect wind no matter what direction it is blowing. Since it does not move, the main body can be made larger and taller. This means that more equipment can be housed in the mill, and that taller sails can be used to collect even more wind. Most smock mills are eight sided although this can vary from six to 12.

Tower mills are further improvements on smock mills. They have a rotating cap and permanent body, but this body is made of brick or stone. This fact makes it possible for the towers to be rounded. A round structure allows for even larger and taller towers. Additionally, brick and stone make the tower windmills the most weather resistant design.

While the previous windmill designs are for larger structures that could service entire towns, the fan-type windmill is made specifically for individuals. It is much smaller and used primarily for pumping water. It consists of a fixed tower (mast), a wheel and tail assembly (fan), a head assembly, and a pump. The masts can be 10-15 ft (3-15 m) high. The number of blades can range from four to 20 and have a diameter between 6 and 16 ft (1.8-4.9 m).

Raw Materials

Windmills can be made with a variety of materials. Post mills are made almost entirely of wood. A lightweight wood, like balsa wood, is used for the fan blades and a stronger, heavier wood is used for the rest of the structure. The wood is coated with paint or a resin to protect it from the outside environment. The smock and tower mills, built by the Dutch and British prior to the twentieth century, use many of the same materials used for the construction of houses including wood, bricks and stones.

The main body of the fan-type mills is made with galvanized steel. This process of treating steel makes it weather resistant and strong. The blades of the fan are made with a lightweight, galvanized steel or aluminum. The pump is made of bronze and brass that inhibits freezing. Leather or synthetic polymers are used for washers and o-rings.

The Manufacturing
Process

Windmills are always erected on site using pre-made parts. The following description relates to the fan-type windmill. The basic steps include making the parts and then assembling the structure.

Making the tower parts

• The tower parts are made from galvanized steel. This process begins with a roll of coiled sheet metal. The coils are put on a de-spooling device and fed to the production line. They are run under a straightener to remove any kinks or twists. The pieces are cut to the appropriate size and shape. In some cases, pieces may be put on a machine that rolls them and welds the seam. The ends are passed under a crimping machine and the pieces are moved to the finishing station.
• At the finishing station, holes are drilled in the metal parts at specific places as required by the windmill design. The parts may also be painted or coated before being arranged in the final windmill kit.

Making the gearbox

• The gearbox is an intricate assembly made up of various gears, axles, rotors, and wheels. The parts are die cast and assembled by hand. The are placed in an weather resistant housing that is designed to accommodate the gearbox parts and the attached wheel and tail assembly.

Making the fan

• The fan is made up of a metal rim with slightly curved blades attached. The rim is produced on a machine that rolls steel strips into circular hoops. A hole is drilled in both ends, and they are connected with a small clamp and screw after the fan blades are attached. A center axle is then connected to the rim and attached with small steel spokes. A typical design will have five pairs of spokes attached a evenly spaced intervals along the rim.
• The fan blades and tail are cut from pieces of sheet metal. The blades are then run through a machine that gives them a slight curve. They are attached to the metal rim with small bolts and metal clamps. They are attached in such a way that they can be raised or lowered depending on the wind conditions.

Preparing the site

• Finding and preparing the construction site is a crucial step in creating a functional windmill. First, an area with a prevailing wind of at least 15 mph (24 km/hr) is needed. Then the area needs to be cleared of trees and other structures that may block wind. In some cases, a dirt mound or concrete base is erected to raise the windmill off the surface to catch more wind.

Final assembly

• The parts of the main body are connected first. They are bolted together on the ground and then raised up vertically. The outer poles are joined with the connecting rods. Clamps are bolted at each joint for stability. After the tower is raised it is loosely bolted to the solid base. Next stay wires are strung from the frame down to the ground and attached to tensioners and ground anchors. When the structure is level, the bolts are tightened and the structure integrity is tested. In some cases a ladder is built into the frame design to allow access to the fan on top which makes cleaning an maintenance easier.
• The fan wheel, gearbox, and main shaft are next attached. The gearbox is first clamped and bolted to the top of the tower. The main shaft is then inserted into the bottom of the gearbox. Next, the fan and its attached axle are connected to the gearbox. Finally, the tail section is attached to the gearbox. The pump is then hooked up to the main shaft and the windmill is operational.

Quality Control

Various tests may be done to ensure that each part of the windmill meets the specifications laid out in the design phase. The most basic of these are simple visual inspections. These will catch most of the obvious production flaws. Since windmills are erected by hand, the quality of each part goes through an additional visual inspection. The quality of workmanship that goes into construction of the windmill will be primarily responsible for the quality of the finished product. To ensure that it remains efficient during operation, regular maintenance checks are necessary.

The Future

Windmills have changed little over the last hundred years. In fact, one basic design conceived in the 1870s is still sold today. The major improvements have come in the types of materials used in construction. This trend will likely continue in future windmill products. However, the future of harnessing wind power is not in traditional windmills at all. The United States government has spent millions of dollars researching and developing wind turbines for electricity generation. In California, numerous wind farms are already in operation. Various other states and cities have plans for creating similar wind farms. In the future, wind power promises to be an environmentally friendly substitute for fossil fuels.

Where to Learn More

Books

Baker, T. Lindsay. North American Windmill Manufacturers' Trade Literature. University of Oklahoma Press, 1998.

Clegg, Alan John. Windmills. Horseshoe Publications, 1995.

Hills, Richard L. Power from Wind: A History of Windmill Technology. Cambridge University Press, 1994.

Hooker, Jeremy. In Praise Of Windmills. Circle Press Pubns, 1990.

Watts, Martin. Water and Wind Power. Shire Publications, 2000.

[Article by: Perry Romanowski]

A large machine in which the wind acts on a number of vanes or blades, rotating them about an axis, thereby producing mechanical power; once widely used for grinding grain, sawing timber, and pumping water. The earliest windmills in America (similar to those in the Netherlands) had four very large, slowly moving blades that were cloth-covered, and required the constant attendance of an operator. In 1854, a patent was issued for an entirely new type of windmill, having a large number of small blades, which was self-regulating and could operate without human intervention; this feature greatly increased its practical application, especially for pumping water. In the latter part of the 20th century, large two-bladed windmills have been assembled in large groups called “farms” for the environment-friendly generation of electrical power.

In the seventeenth century windmills stood in what are now New York and northern New Jersey, but they did not become a feature of American life until after the Civil War, and then generally in the western United States. The occupation of lands beyond the belt of regular rain, springs, streams, and shallow underground water tapped by hand-dug wells made windmills a necessity. Well-drilling machinery and practical mills made their use possible. Popularized in the 1870s, windmills came to dot the Prairie states and the rough, arid, or semiarid lands beyond. They provided a way, before the invention of the gasoline engine, to supply water for personal and agricultural use.

The windmill became common only after barbed wire had made the control of waterings by private owners possible. It turned tens of millions of acres of waterless land into farms. It made garden patches and shade and fruit trees possible, even during the most parching droughts. It also brought running water into homes.

Nonetheless, the use of windmills to provide water in dry western states has not been an unmitigated good. For instance, since the 1940s, farmers from northern Texas to southern South Dakota have depended on water pumped from the Ogallala Aquifer to irrigate their crops. Although this massive subterranean aquifer is the largest in the world, those who rely on it are consuming its water at a faster rate than the aquifer can recharge it. Therefore, this practice is not sustainable. Calling the transformation of arid territory into farms "land reclamation" falsely implies that the so-called Great American Desert served no purpose before irrigation. The fact that an area does not easily support humans and their preferred crops does not render it worthless. A more sustainable use for windmills is in the production of electricity from wind power, an area in which Denmark excelled during the early 2000s.

Bibliography

Hills, Richard Leslie. Power from Wind: A History of Windmill Technology. New York: Cambridge University Press, 1994.

MacDonnell, Lawrence J. From Reclamation to Sustainability: Water, Agriculture, and the Environment in the American West. Niwot: University Press of Colorado, 1999.

Opie, John. Ogallala: Water for a Dry Land. 2d ed. Lincoln: University of Nebraska Press, 2000.

Rowley, William D. Reclaiming the Arid West: The Career of Francis G. Newlands. Bloomington: Indiana University Press, 1996.

From our Archives: Today's Highlights, May 8, 2010

LearnThatWord.com is a free vocabulary and spelling program where you only pay for results!

• Machinery and Mechanical Devices - windmill: mill operated by large oblique vanes that radiate from shaft and rotate by force of wind
• Tools, Machinery, and Structures - windmill: machine for grinding grain powered by wind’s rotation of large oblique vanes radiating from shaft
• Boxing and Wrestling
• Toys and Playthings
• Directions - windmill: move like a windmill, esp. by rotating one’s arms in wide arcs

For other uses, see Windmill (disambiguation).

Windmill De Kameel in Schiedam, Netherlands

A windmill is a machine which converts the energy of wind into rotational energy by means of vanes called sails or blades.^[1][2] Originally windmills were developed for milling grain for food production. In the course of history the windmill was adapted to many other industrial uses.^[3] An important application was to pump water. Windmills used for generating electricity are commonly known as wind turbines.

Contents 1 Windmills in antiquity 2 Horizontal windmills 3 Vertical windmills 3.1 Post mill 3.2 Hollow-post mill 3.3 Tower mill 3.4 Smock mill 3.5 Sails 3.6 Machinery 3.7 Spread and decline 4 Windpumps 5 Wind turbine 6 See also 7 References 8 Further reading 9 External links

Windmills in antiquity

Heron's wind-powered organ

The windwheel of the Greek engineer Heron of Alexandria in the 1st century AD is the earliest known instance of using a wind-driven wheel to power a machine.^[4][5] Another early example of a wind-driven wheel was the prayer wheel, which was used in ancient Tibet and China since the 4th century.^[6] It has been claimed that the Babylonian emperor Hammurabi planned to use wind power for his ambitious irrigation project in the 17th century BC.^[7]

Horizontal windmills

The Persian horizontal windmill

The first practical windmills had sails that rotated in a horizontal plane, around a vertical axis.^[8] According to Ahmad Y. al-Hassan, these Panemone windmills were invented in eastern Persia as recorded by the Persian geographer Estakhri in the 9th century.^[9][10] The authenticity of an earlier anecdote of a windmill involving the second caliph Umar (AD 634–644) is questioned on the grounds that it appears in a 10th-century document.^[11] Made of six to twelve sails covered in reed matting or cloth material, these windmills were used to grind grain or draw up water, and were quite different from the later European vertical windmills. Windmills were in widespread use across the Middle East and Central Asia, and later spread to China and India from there.^[12]

A similar type of horizontal windmill with rectangular blades, used for irrigation, can also be found in 13th-century China (during the Jurchen Jin Dynasty in the north), introduced by the travels of Yelü Chucai to Turkestan in 1219.^[13]

Hooper's Mill, Margate, Kent. An 18th Century European horizontal windmill

Horizontal windmills were built, in small numbers, in Europe during the eighteenth and nineteenth centuries,^[8] for example Fowler's Mill at Battersea in London, and Hooper's Mill at Margate in Kent. These early modern examples seem not to have been directly influenced by the horizontal windmills of the Middle and Far East, but to have been independent inventions by engineers influenced by the Industrial Revolution.^[14]

Vertical windmills

There is an ongoing debate among historians on whether and how the windmill from the middle East influenced the development of the early European windmill.^{[15][16][17][18]} In northwestern Europe, the horizontal-axis or vertical windmill (so called due to the plane of the movement of its sails) is believed to date from the last quarter of the 12th century in the triangle of northern France, eastern England and Flanders. The earliest certain reference to a windmill in Europe (assumed to have been of the vertical type) dates from 1185, in Weedley, Yorkshire, although a number of earlier but less certainly dated twelfth century European sources referring to windmills have also been found.^[19] These earliest mills were used to grind cereals.

Post mill

A windmill on the background of the 1792 Battle of Valmy, France.

Main article: Post mill

The evidence at present is that the earliest type of European windmill 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 wind direction; an essential requirement for windmills to operate economically in North-Western Europe, where wind directions are variable. The body contains all the milling machinery. The first post mills were of the sunken type where the post was buried in an earth mound to support it. Later a wooden support was developed called the trestle. This was often covered over or surrounded by a roundhouse to protect the trestle from the weather and to provide storage space. This type of windmill was the most common in Europe until the 19th century when more powerful tower and smock mills replaced them.

Hollow-post mill

In a hollow-post mill the post on which the body is mounted is hollowed out, to accommodate the drive shaft.^[20] In this way it is possible to drive machinery below or outside the body while still being able to rotate the body into the wind. Hollow-post mills driving scoop wheels were used in the Netherlands to drain wetlands from the 14th century onwards.

Tower mill

Main article: Tower mill

By the end of the thirteenth century the masonry tower mill, on which only the cap is rotated rather than the whole body of the mill, had been introduced. The spread of tower mills came with a growing economy that called for larger and more stable sources of power though they were more expensive to build. In contrast to the post mill, only the cap of the tower mill needs to be turned into the wind, so the main structure can be made much taller, allowing the sails to be made longer, which enables them to provide useful work even in low winds. The cap can be turned into the wind either by winches or gearing inside the cap or from a winch on the tail pole outside the mill. A method of keeping the cap and sails into the wind automatically is by using a fantail, a small windmill mounted at right angles to the sails, at the rear of the windmill. These are also fitted to tail poles of post mills and are common in Great Britain and English-speaking countries of the former British Empire, Denmark and Germany but rare in other places. Tower mills with a fixed cap are found around the Mediterranean Sea. They are built with the sails facing the prevailing wind direction.

Smock mill

Main article: Smock mill

The smock mill is a later development of the tower mill where the tower is replaced by a wooden framework, called the "smock." The smock is commonly of octagonal plan, though examples with more, or fewer, sides exist. The smock is thatched, boarded or covered by other materials like slate, sheet metal or tar paper. The lighter construction in comparison to tower mills make smock mills practical as drainage mills as these often had to be built in areas with unstable subsoil. Having originated as a drainage mill, smock mills are also used for a variety of purposes. When used in a built-up area it is often placed on a masonry base to raise it above the surrounding buildings.

• 

  Smock mill De 1100 Roe, Amsterdam, Netherlands, built in 1757, type called a grondzeiler ("ground sailer") by the Dutch , since the sails almost reach the ground.

• 

  Post mill of Talcy, France with medieval style sails

• 

  Groenendijkse Molen. A hollow post drainage mill

• 

  Wilton Windmill. A tower mill with fantail

• 

  Beacon Mill, a smock mill of 1802

• 

  A smock mill with a stage on a brick base in Sønderho, Fanø, Denmark

• 

  Tower mill with jib sails in Antimahia, Kos, Greece

Sails

Main article: Windmill sail

Common sails consist of a lattice framework on which a sailcloth is spread. The miller can adjust the amount of cloth spread according to the amount of wind available and power needed. In medieval mills the sailcloth was wound in and out of a ladder type arrangement of sails. Post-medieval mill sails had a lattice framework over which the sailcloth was spread, while in colder climates the cloth was replaced by wooden slats, which were easier to handle in freezing conditions.^[21] The jib sail is commonly found in Mediterranean countries, and consists of a simple triangle of cloth wound round a spar. In all cases the mill needs to be stopped to adjust the sails. Inventions in Great Britain in the late 18th and 19th century led to sails that automatically adjust to the wind speed without the need for the miller to intervene, culminating in Patent sails invented by William Cubitt in 1813. In these sails the cloth is replaced by a mechanism of connected shutters. In France, Berton invented a system consisting of longitudinal wooden slats connected by a mechanism that lets the miller open them while the mill is turning. In the 20th century increased knowledge of aerodynamics from the development of the airplane led to further improvements in efficiency by German engineer Bilau and several Dutch millwrights. The majority of windmills have four sails. Multi-sailed mills, with five, six or eight sails, were built in Great Britain (especially in and around the counties of Lincolnshire and Yorkshire), Germany and less commonly elsewhere. Earlier multi-sailed mills are found in Spain, Portugal, Greece, parts of Romania, Bulgaria and Russia ^[22] A mill with an even number of sails has the advantage of being able to run with a damaged sail and the one opposite removed without resulting in an unbalanced mill.

Machinery

Main article: Mill machinery

Interior view, Pantigo windmill, East Hampton, New York. Historic American Buildings Survey

Gears inside a windmill convey power from the rotary motion of the sails to a mechanical device. The sails are carried on the horizontal windshaft. Windshafts can be wholly made of wood, or wood with a cast iron poll end (where the sails are mounted) or entirely of cast iron. The brake wheel is fitted onto the windshaft between the front and rear bearing. It has the brake around the outside of the rim and teeth in the side of the rim which drive the horizontal gearwheel called wallower on the top end of the vertical upright shaft. In grist mills the great spur wheel, lower down the upright shaft, drives one or more stone nuts on the shafts driving each millstone. Post mills sometimes have a head and/or tail wheel driving the stone nuts directly, instead of the spur gear arrangement. Additional gear wheels drive a sack hoist or other machinery. The machinery differs if the windmill is used for other applications than milling grain. A drainage mill uses another set of gear wheels on the bottom end of the upright shaft to drive a scoop wheel or Archimedes' screw. Sawmills use a crankshaft with to provide a reciprocating motion to the saws. Windmills have been used to power many other industrial processes, including papermills, threshing mills, and for example to process oil seeds, wool, paints and stone products ^[3]

• 

  An isometric drawing of the machinery of the Beebe Windmill.

• 

  Diagram of the smock mill at Meopham, Kent

• 

  Cross section of a post mill

• 

  Windshaft, brake wheel and brake blocks in smock mill d'Admiraal in Amsterdam

Spread and decline

Oilmill De Zoeker, paintmill De Kat and paltrok sawmill De Gekroonde Poelenburg at the Zaanse Schans

The total number of wind powered mills in Europe is estimated to have been around 200,000 at its peak, compared to some 500,000 waterwheels.^[21] With the coming of the industrial revolution, the importance of wind (and water) as primary industrial energy source declined and was eventually replaced by steam (in steam mills) and internal combustion engines, although windmills continued to be built in large numbers until late in the 19th Century. More recently windmills have been preserved for their historic value, in some cases as static exhibits when the antique machinery is too fragile to put in motion, and in other cases as fully working mills. There are around 50 working mills in operation in Britain as of 2009.^[23]

Of the 10,000 windmills in use in the Netherlands around 1850,^[24] about 1000 are still standing. Most of these are being run by volunteers though there are some grist mills still operating commercially. Many of the drainage mills have been appointed as backup to the modern pumping stations. The Zaan district has been said to have been the first industrialized region of the world with around 600 operating wind powered industries by the end of the 18th century.^[24] Economic fluctuations and the industrial revolution had a much greater impact on these industries than on grain and drainage mills so only very few are left.

Construction of mills spread to the Cape Colony in the 17th century. The early tower-mills did not survive the gales of the Cape Peninsula, so that in 1717 the Heeren XVII sent carpenters, masons and materials to construct a durable mill. The mill was completed in 1718 and became known as the Oude Molen and was located between Pinelands Station and the Black River. Long since demolished, its name lives on as that of a Technical school in Pinelands. By 1863 Cape Town could boast eleven mills stretching from Paarden Eiland to Mowbray. ^[25]

Windpumps

Windpump in South Dakota, USA

Main article: Windpump

Windpumps are used extensively on farms and ranches in the central plains and South West of the United States and in Southern Africa and Australia. These mills feature a large number of blades so that they turn slowly with considerable torque in low winds and be self regulating in high winds. A tower-top gearbox and crankshaft convert the rotary motion into reciprocating strokes carried downward through a rod to the pump cylinder below. The farm wind pump was invented by Daniel Halladay in 1854.^[26][27] In early California and some other states the windmill was part of a self-contained domestic water system including a hand-dug well and a redwood water tower supporting a redwood tank and enclosed by redwood siding (tankhouse). Eventually steel blades and steel towers replaced wooden construction, and at their peak in 1930, an estimated 600,000 units were in use.^[28] The multi-bladed wind turbine atop a lattice tower made of wood or steel hence became, for many years, a fixture of the landscape throughout rural America. Firms such as Star, Eclipse, Fairbanks-Morse and Aermotor became famed suppliers in North and South America.

Wind turbine

Main article: Wind power

A windmill used to generate electricity is commonly called a wind turbine. The first windmills for electricity production were built by the end of the 19th century by Prof James Blyth in Scotland (1887),^[29][30] Charles F. Brush in Cleveland, Ohio (1887–1888)^[31][32][33] and Poul la Cour in Denmark (1890s). La Cour's mill from 1896 later became the local powerplant of the village Askov. By 1908 there were 72 wind-driven electric generators in Denmark from 5 kW to 25 kW. By the 1930s windmills were widely used to generate electricity on farms in the United States where distribution systems had not yet been installed, built by companies like Jacobs Wind, Wincharger, Miller Airlite, Universal Aeroelectric, Paris-Dunn, Airline and Winpower and by the Dunlite Corporation for similar locations in Australia.

Rønland Windpark in Denmark

Forerunners of modern horizontal-axis utility-scale wind generators were the WIME-3D in service in Balaklava USSR from 1931 until 1942, a 100 kW generator on a 30 m (100 ft) tower,^[34] the Smith-Putnam wind turbine built in 1941 on the mountain known as Grandpa's Knob in Castleton, Vermont, USA of 1.25 MW^[35] and the NASA wind turbines developed from 1974 through the mid 1980's. The development of these 13 experimental wind turbines pioneered many of the wind turbine design technologies in use today, including: steel tube towers, variable-speed generators, composite blade materials, partial-span pitch control, as well as aerodynamic, structural, and acoustic engineering design capabilities. The modern wind power industry began in 1979 with the serial production of wind turbines by Danish manufacturers Kuriant, Vestas, Nordtank, and Bonus. These early turbines were small by today's standards, with capacities of 20–30 kW each. Since then, they have increased greatly in size, with the Enercon E-126 capable of delivering up to 7 MW, while wind turbine production has expanded to many countries.

As the 21st century began, rising concerns over energy security, global warming, and eventual fossil fuel depletion led to an expansion of interest in all available forms of renewable energy. Worldwide there are now many thousands of wind turbines operating, with a total nameplate capacity of 194,400 MW.^[36] Europe accounted for 48% of the total in 2009.

A wind turbine looking like a windmill is De Nolet in Rotterdam.

See also

Renewable energy portal

Wikimedia Commons has media related to: Multi-sailed windmills

• List of windmills
• Mill machinery
• Millstone
• Molinology
• Éolienne Bollée
• Renewable energy
• Watermill

References

1. ^ Mill definition
2. ^ Windmill definition stating that a windmill is a mill or machine operated by the wind
3. ^ ^{a b} Gregory, R. The Industrial Windmill in Britain. Phillimore, 2005
4. ^ Dietrich Lohrmann, "Von der östlichen zur westlichen Windmühle", Archiv für Kulturgeschichte, Vol. 77, Issue 1 (1995), pp.1-30 (10f.)
5. ^ A.G. Drachmann, "Heron's Windmill", Centaurus, 7 (1961), pp. 145-151
6. ^ Lucas, Adam (2006). Wind, Water, Work: Ancient and Medieval Milling Technology. Brill Publishers. p. 105. ISBN 9004146490. 
7. ^ Sathyajith, Mathew (2006). Wind Energy: Fundamentals, Resource Analysis and Economics. Springer Berlin Heidelberg. pp. 1–9. ISBN 978-3-540-30905-5. 
8. ^ ^{a b} Wailes, R. Horizontal Windmills. London, Transactions of the Newcomen Society vol.XL 1967-68 pp125-145
9. ^ دانره المعارف بزرگ اسلامی - اصطخري‌، ابواسحاق‌
10. ^ Ahmad Y Hassan, Donald Routledge Hill (1986). Islamic Technology: An illustrated history, p. 54. Cambridge University Press. ISBN 0-521-42239-6.
11. ^ Dietrich Lohrmann, "Von der östlichen zur westlichen Windmühle", Archiv für Kulturgeschichte, Vol. 77, Issue 1 (1995), pp. 1–30 (8)
12. ^ Donald Routledge Hill, "Mechanical Engineering in the Medieval Near East", Scientific American, May 1991, p. 64–69. (cf. Donald Routledge Hill, Mechanical Engineering)
13. ^ Needham, Volume 4, Part 2, 560.
14. ^ Hills, R L. Power from Wind: A History of Windmill Technology. Cambridge University Press 1993
15. ^ Farrokh, Kaveh (2007), Shadows in the Desert, Osprey Publishing, p. 280, ISBN 1-84603-108-7 
16. ^ Lynn White Jr. Medieval technology and social change (Oxford, 1962) p. 86 & p. 161–162
17. ^ Lucas, Adam (2006), Wind, Water, Work: Ancient and Medieval Milling Technology, Brill Publishers, pp. 106–7, ISBN 90-04-14649-0 
18. ^ Bent Sorensen (November 1995), "History of, and Recent Progress in, Wind-Energy Utilization", Annual Review of Energy and the Environment 20 (1): 387–424, doi:10.1146/annurev.eg.20.110195.002131 
19. ^ Lynn White Jr., Medieval technology and social change (Oxford, 1962) p. 87.
20. ^ Martin Watts (2006). Windmills. Osprey Publishing. p. 55. ISBN 9780747806530. http://books.google.com/books?id=PJ7-M8lFo_UC&pg=PA55. 
21. ^ ^{a b} http://www.lowtechmagazine.com/2009/10/history-of-industrial-windmills.html
22. ^ Wailes, Rex (1954), The English Windmill, London: Routlege & Kegan Paul, pp. 99–104 
23. ^ Victorian Farm, Episode 1. Directed and produced by Naomi Benson. BBC Television
24. ^ ^{a b} Endedijk, L and others. Molens, De Nieuwe Stockhuyzen. Wanders. 2007. ISBN 978 90 400 8785 1
25. ^ http://mostertsmill.co.za/index.php?option=com_content&view=article&id=58&Itemid=53
26. ^ americanheritage.com
27. ^ fnal.gov
28. ^ Paul Gipe, Wind Energy Comes of Age, John Wiley and Sons, 1995 ISBN 0-471-10924-X, pages 123-127
29. ^ Price, Trevor J (3 May 2005). "James Blyth - Britain's first modern wind power engineer". Wind Engineering 29 (3): 191–200. doi:10.1260/030952405774354921. http://www.ingentaconnect.com/content/mscp/wind/2005/00000029/00000003/art00002. ^{[dead link]}
30. ^ Shackleton, Jonathan. "World First for Scotland Gives Engineering Student a History Lesson". The Robert Gordon University. http://www.rgu.ac.uk/pressrel/BlythProject.doc. Retrieved 20 November 2008. 
31. ^ [Anon, 1890, 'Mr. Brush's Windmill Dynamo', Scientific American, vol 63 no. 25, 20th Dec, p. 54]
32. ^ A Wind Energy Pioneer: Charles F. Brush, Danish Wind Industry Association. Accessed 2007-05-02.
33. ^ History of Wind Energy in Cutler J. Cleveland,(ed) Encyclopedia of Energy Vol.6, Elsevier, ISBN 978-1-60119-433-6, 2007, pp. 421-422
34. ^ Erich Hau, Wind turbines: fundamentals, technologies, application, economics, Birkhäuser, 2006 ISBN 3540242406, page 32, with a photo
35. ^ The Return of Windpower to Grandpa's Knob and Rutland County, Noble Environmental Power, LLC, 12 November 2007. Retrieved from Noblepower.com website 10 January 2010. Comment: this is the real name for the mountain the turbine was built, in case you wondered.
36. ^ Global wind energy council

Further reading

• Ahmad Y Hassan, Donald Routledge Hill (1986). Islamic Technology: An illustrated history. Cambridge University Press. ISBN 0-521-42239-6.
• Chartrand, French Fortresses in North America 1535–1763: Quebec, Montreal, Louisbourg and New Orleans.
• Dietrich Lohrmann, "Von der östlichen zur westlichen Windmühle", Archiv für Kulturgeschichte, Vol. 77, Issue 1 (1995)
• A.G. Drachmann, "Heron's Windmill", Centaurus, 7 (1961).
• Needham, Joseph (1986). Science and Civilization in China: Volume 4, Physics and Physical Technology, Part 2, Mechanical Engineering. Taipei: Caves Books Ltd.
• Hugh Pembroke Vowles: "An Enquiry into Origins of the Windmill", Journal of the Newcomen Society, Vol. 11 (1930–31)
• Roy Gregory and Laurence Turner (2009) Windmills of Yorkshire ISBN 978-1-84033-475-3
• Edwin Tunis (1999), Colonial living, The Johns Hopkins University Press ", ISBN 0-8018-6227-2, pp. 72 and 73

External links

• Architecture: Windmills at the Open Directory Project
• Earth Science Australia, Wind Power and Windmills
• The International Molinological Society
• Windmills at Windmill World
• Mill Database, Belgium and Netherlands
• A Geograph article and photo-record of Windmills in Great Britian

v d e Wind power Wind power Environmental effects History Vehicles Offshore wind power Wind turbine Windmill Kitegen Wind power by country Asia Australia Austria Belgium Canada China Croatia Denmark Estonia European Union Finland France Germany Greece Hungary India Iran Ireland Italy Japan Malta Netherlands New Zealand Pakistan Portugal Romania Scotland Serbia Spain Sweden Turkey UK US Wind turbines Aerodynamics Airborne Darrieus Design Floating Savonius Quietrevolution Small Unconventional Vertical axis Devices in use Wind power industry Consultants Manufacturers Software Wind farm management Wind farms Community-owned List of offshore wind farms List of onshore wind farms Concepts Betz' law Capacity factor EROEI Grid energy storage HVDC Intermittency Net energy gain Storage Subsidies Wind power forecasting Wind profile power law Wind resource assessment

This entry is from Wikipedia, the leading user-contributed encyclopedia. It may not have been reviewed by professional editors (see full disclaimer)

Dansk (Danish)
n. - vindmølle, vejrmølle, helikopter
v. intr. - flyve med helikopter
v. tr. - få til at dreje som en vindmølle

Nederlands (Dutch)
windmolen

Français (French)
n. - moulin à vent
v. intr. - tourner avec la force du passage du courant atmosphérique (une hélice d'avion)
v. tr. - faire tourner avec la force du passage du courant atmosphérique (une hélice d'avion)

Deutsch (German)
n. - Windmühle, Windrädchen
v. - eine Windmühle bewegen

Ελληνική (Greek)
n. - ανεμόμυλος

Italiano (Italian)
mulino a vento, mulinello

idioms:

• tilt at windmills    combattere contro mulini a vento

Português (Portuguese)
n. - moinho de vento (m)

idioms:

• tilt at windmills    lutar contra inimigos imaginários

Русский (Russian)
ветряная мельница, ветродвигатель

idioms:

• tilt at windmills    сражаться с ветряными мельницами

Español (Spanish)
n. - molino de viento, molinillo
v. intr. - mover los brazos como las aspas de un molino
v. tr. - hacer mover los brazos como las aspas de un molino

Svenska (Swedish)
n. - väderkvarn

中文（简体）(Chinese (Simplified))
风车, 旋转玩具, 风车房, 作风车般旋转, 使旋转

中文（繁體）(Chinese (Traditional))
n. - 風車, 旋轉玩具, 風車房
v. intr. - 作風車般旋轉
v. tr. - 使旋轉

한국어 (Korean)
n. - 풍차, 헬리콥터
v. intr. - 풍차의 바람개비 등을 암시하며 동그라미를 그리다
v. tr. - 풍차의 바람개비 등을 암시하며 동그라미를 그리다

日本語 (Japanese)
n. - 風車, ヘリコプター
v. - 風車のように回す, 気流の力で回す

العربيه (Arabic)
‏(الاسم) الطاحونه الهوائيه, دولاب الطاحونه الهوائيه, الحوامه, عدو وهمي‏

עברית (Hebrew)
n. - ‮טחנת-רוח, גלגילון רוח‬
v. intr. - ‮התנועע ככנפי טחנת-רוח‬
v. tr. - ‮התנועע ככנפי טחנת-רוח‬

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