Editing Windpump

{{Short description|A wind turbine for pumping water}}

A '''windpump''' is a wind-driven device which is used for pumping [[water]].
[[File:KinderdijkWindmills.jpg|thumb|right|The [[windmills at Kinderdijk]] in the village of [[Kinderdijk]], Netherlands is a [[UNESCO]] [[World Heritage Site]]]]
[[File:Molendeolifant.jpg|thumb|[[De Olifant, Burdaard|De Olifant]] at [[Burdaard]], [[Friesland]]]]
Windpumps were used to pump water since at least the 9th century in what is now [[Afghanistan]], [[Iran]] and [[Pakistan]].<ref>{{cite book |first=Adam |last=Lucas |year=2006 |title=Wind, Water, Work: Ancient and Medieval Milling Technology |publisher=Brill Publishers |isbn=90-04-14649-0 |page=61}}</ref> The use of wind pumps became widespread across the [[Muslim world]] and later spread to [[China]] and [[Indian subcontinent|India]].<ref>{{cite web|url=http://home.swipnet.se/islam/articles/HistoryofSciences.htm|archive-url=https://web.archive.org/web/20070524071743/http://home.swipnet.se/islam/articles/HistoryofSciences.htm|archive-date=May 24, 2007|title=History of Sciences in the Islamic World|website=swipnet.se|access-date=August 20, 2021}}</ref> Windmills were later used extensively in Europe, particularly in the [[Netherlands]] and the [[East Anglia]] area of [[Great Britain]], from the late [[Middle Ages]] onwards, to drain land for agricultural or building purposes.

[[Simon Stevin]]'s work in the ''waterstaet'' involved improvements to the [[sluice]]s and [[spillway]]s to control [[flood]]ing. [[Windmill]]s were already in use to pump the water out, but in ''Van de Molens'' (''On mills''), he suggested improvements, including the idea that the wheels should move slowly, and a better system for meshing of the [[gear teeth]]. These improvements increased the efficiency of the windmills used to pump water out of the [[polder]]s by three times. He received a [[patent]] on his innovation in 1586.<ref name=isis/>

Eight- to ten-bladed windmills were used in the [[Region of Murcia]], [[Spain]], to raise water for irrigation purposes.<ref>{{cite web|url=http://www.yachtmollymawk.com/2008/11/spanish-water-works/|title=Spanish Water Works|last=Schinas|first=Jill|website=yachtmollymawk.com|year=2008|access-date=August 20, 2021}}</ref> The drive from the windmill's rotor was led down through the tower and back out through the wall to turn a large wheel known as a ''[[noria]]''. The ''noria'' supported a bucket chain which dangled down into the well. The buckets were traditionally made of wood or clay. These windmills remained in use until the 1950s, and many of the towers are still standing.

Early immigrants to the [[New World]] brought with them the technology of windmills from Europe.<ref name="Brief History">{{cite web|url=http://www.windmillersgazette.com/history.html|archive-url=https://web.archive.org/web/20111007162315/http://www.windmillersgazette.com/history.html|archive-date=October 7, 2011|website=windmillersgazette.com|title=Brief History of Windmills in the New World|last=Baker|first=T. Lindsay|access-date=August 20, 2021}}</ref> On US farms, particularly on the [[Great Plains]], wind pumps were used to pump water from farm wells for cattle. In 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]]). The self-regulating farm wind pump was invented by [[Daniel Halladay]] in 1854.<ref name="Brief History" /><ref>{{cite journal|url=https://www.fnal.gov/pub/ferminews/ferminews03-02-14/p4.html|title=Historic Turns in The Windmill City|last=Clements|first=Elizabeth|journal=Fermi News|volume=26|issue=3|year=2003|publisher=[[Fermilab]]|access-date=August 20, 2021}}</ref> Eventually, steel blades and steel towers replaced wooden construction, and at their peak in 1930, an estimated 600,000 units were in use, with capacity equivalent to 150 megawatts.<ref>{{cite book|title=Wind Energy Comes of Age|last=Gipe|first=Paul|pages=123–127|publisher=John Wiley and Sons|year=1995|isbn=0-471-10924-X}}</ref> Very large lighter wind pumps in Australia directly crank the pump with the rotor of the windmill. Extra back gearing between small rotors for high wind areas and the pump crank prevents trying to push the pump rods down on the downstroke faster than they can fall by gravity. Otherwise pumping too fast leads to the pump rods buckling, making the seal of the stuffing box leak and wearing through the wall of the rising main (UK) or the drop-pipe (US) so all output is lost.

The multi-bladed wind pump or wind [[turbine]] atop a lattice tower made of wood or steel hence became, for many years, a fixture of the landscape throughout rural America.<ref>{{cite web|url=https://www.semprius.com/wind-turbines-vs-windmills/|title=Wind Turbines vs. Windmills: What's the Difference?|last=Duval|first=George|website=semprius.com|date=July 18, 2021|access-date=August 20, 2021}}</ref> These mills, made by a variety of manufacturers, featured many blades so that they would turn slowly with considerable [[torque]] in moderate winds and be self-regulating in high winds. A tower-top [[Transmission (mechanics)|gearbox]] and [[crankshaft]] converted the rotary motion into reciprocating strokes carried downward through a rod to the pump cylinder below. Today, rising energy costs and improved pumping technology are increasing interest in the use of this once declining technology.

==Worldwide use==
[[File:Wicken Fen Windpump.jpg|thumb|A working wooden windpump on [[The Fens]] in [[Cambridgeshire]], UK]]
The [[Netherlands]] is well known for its windmills. Most of 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]].

In the UK, the term ''windpump'' is rarely used, and they are better known as ''drainage windmills''. Many of these were built in [[The Broads]] and [[The Fens]] of [[East Anglia]] for the draining of land, but most of them have since been replaced by [[diesel fuel|diesel]] or electric powered pumps.<ref>{{cite book|url=https://books.google.com/books?id=K-JRAQAAIAAJ&pg=PA106|page=106|title=The Norfolk Broads: A Landscape History|last=Williamson|first=Tom|publisher=Manchester University Press|year=1997|isbn=9780719048005}}</ref> Many of the original windmills still stand in a derelict state although some have been restored.{{citation needed|date=July 2022}}

Windpumps are used extensively in [[Southern Africa]], Australia, and on farms and ranches in the central plains and Southwest of the United States. 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.

[[Kenya]] has also benefited from the African development of windpump technologies. At the end of the 1970s, the UK [[NGO]] [[Intermediate Technology Development Group]] provided engineering support to the Kenyan company Bobs Harries Engineering Ltd for the development of the Kijito windpumps. Bobs Harries Engineering Ltd is still manufacturing the Kijito windpumps, and more than 300 of them are operating in the whole of [[East Africa]].{{citation needed|date=August 2021}}

In many parts of the world, a [[rope pump]] is being used in conjunction with wind turbines. This easy-to- construct pump works by pulling a knotted rope through a pipe (usually a simple PVC pipe) causing the water to be pulled up into the pipe. This type of pump has become common in [[Nicaragua]] and other places.{{citation needed|date=August 2021}}

==Construction==
To construct a windpump, the bladed rotor needs to be matched to the pump. With non-electric windpumps, high [[Blade solidity|solidity]] rotors are best used in conjunction with positive displacement (piston) pumps, because single-acting [[piston pump]]s need about three times as much torque to start them as to keep them going. Low solidity rotors, on the other hand, are best used with [[centrifugal pump]]s, [[waterladder pump]]s and chain and washer pumps, where the torque needed by the pump for starting is less than that needed for running at design speed. Low solidity rotors are best used if they are intended to drive an electricity generator; which in turn can drive the pump.<ref>[http://www.fao.org/docrep/010/ah810e/AH810E10.htm Water lifting devices; matching bladed rotors to pumps]</ref>

==Multi-bladed windpumps==
[[File:Wind-powered-agricultural-pump-1.jpg|thumb|Wind powered water pump on Oak Park Farm, Shedd, Oregon.]]
[[File:Windmill in far western NSW.jpg|thumb|Windpump in far western [[NSW]].]]
Multi-bladed wind pumps can be found worldwide and are manufactured in the United States, Argentina, China, New Zealand, South Africa, and Australia. Commonly known in the US and Canada as a "weathercock" because it behaves much like a traditional weather vane, moving with the direction of the wind (but also measuring wind speed).The Butler brand added improvements to the technology of windpumps in 1897, 1898 and 1905<ref>{{Cite web| url=http://www.vintagewindmillpartslist.com/sitebuildercontent/sitebuilderfiles/butlerpictorial.pdf| title=Butler Pictorial| access-date=2023-07-30}}</ref> A 16&nbsp;ft (4.8&nbsp;m) diameter wind pump can lift up to 1600 US gallons (about 6.4 metric tons) of water per hour to an elevation of 100&nbsp;ft with a 15 to 20&nbsp;mph wind (24–32&nbsp;km/h).<ref>[http://www.ironmanwindmill.com Iron Man Windmill Website pumping capacity calculator], retrieved January 15, 2011</ref> However they take a strong wind to start so they turn over the crank of the piston pump. Wind pumps require little maintenance—usually only a change of gear box oil annually.<ref>[http://www.aermotorwindmill.com/Sales/CommonQuestions.asp Aermotor Web site frequently asked questions], retrieved Sept. 17, 2008</ref> An estimated 60,000 wind pumps are still in use in the United States. They are particularly attractive for use at remote sites where electric power is not available and maintenance is difficult to provide.<ref>{{Cite web| url=http://www.windmill-parts.com/index.html| title=Windmill parts}}</ref>
A common multi-bladed windpump usefully pumps with about 4%–8% of the annual windpower passing through the area it sweeps<ref>[http://www.nrel.gov/docs/fy03osti/30361.pdf Argaw, N.,"Renewable Energy for Water Pumping Applications in Rural Villages", 2003, NREL Report 30361, page 27]</ref><ref>[http://www.cprl.ars.usda.gov/REMM%20Pubs/1997%20Performance%20and%20Economic%20Comparison%20of%20a%20Mechanical%20Windmill%20to%20a%20Wind-Electric%20Water%20Pumping%20System.pdf Brian Vick, Nolan Clark "Performance and Economic Comparison of a Mechanical Windmill to Wind-Electric Water Pumping System", 1997, USDA-Agricultural Research Service, see Figure-2]</ref> This lower conversion is due to poor load matching between wind rotors and fixed-stroke piston pumps.

==Fundamental problems of multi-bladed windpumps==

===Inefficient rotor===
[[File:Derelict windpump with water tank in the foreground next to the Boorowa railway in Galong NSW Australia.JPG|thumb|Derelict water tank with windmill in the background]]
The main design feature of a multi-bladed rotor is "high starting torque", which is necessary for cranking a piston pump operation. Once started a multi-bladed rotor runs at too high a tipspeed ratio at less than its best efficiency of 30%.<ref name="Hau 2005, page 101">Hau, Erich "Wind Turbines", 2005, page 101, Fig.5-10</ref> On the other hand, modern wind rotors can operate at an aerodynamic efficiency of more than 40% at higher tipspeed ratio for a smaller swirl added and wasted to the wind.<ref name="Hau 2005, page 101"/> But they would need a highly variable stroke mechanism rather than just a crank to piston pump.{{citation needed|date=June 2023}}

===Poor load matching===

A multi-bladed windmill is a mechanical device with a piston pump. Because a piston pump has a fixed stroke, the energy demand of this type of pump is proportional to pump speed only. On the other hand, the energy supply of a wind rotor is proportional to the cube of wind speed. Because of that, a wind rotor runs at over speed (more speed than needed), yielding a loss of aerodynamic efficiency.

A variable stroke would match the rotor speed according to wind speed, functioning like a "variable-speed generator". The flow rate of variable stroke windpump can be increased two times, compared to fixed stroke windpumps at the same wind speed.<ref name="ena.com.tr">[https://web.archive.org/web/20161223052210/http://www.ena.com.tr/Wind90.pdf Clark, Nolan "Variable Stroke Pumping for Mechanical Windmills", 1990, AWEA Proceedings]</ref>

===Cyclic torque variation===

A piston pump has a very light suction phase, but the upstroke is heavy and puts a big backtorque on a starting rotor when the crank is horizontal and ascending. A counterweight on the crank up in the tower and yawing with the wind direction can at least spread the torque to the crank descent.{{citation needed|date=June 2023}}

==Development of improved windpumps==

[[File:Windmill-patent-drawing-from-1889-vintage-aged.jpg|thumb|left|Windmill patent drawing from 1889 vintage aged]] [[File:Aldrich-windmill-patent-drawing-from-1889-blue-ink-aged-pixel.jpg|thumb|Aldrich windmill patent drawing from 1889]]

Although multi-bladed windpumps are based on proven technology and are widely used, they have the fundamental problems mentioned above and need a practical variable stroke mechanism.{{citation needed|date=June 2023}}

===USDA experiments at Texas===
Between 1988 and 1990, a variable stroke windpump was tested at the USDA-Agriculture Research Center-Texas, based on two patented designs (Don E. Avery Patent #4.392.785, 1983 and Elmo G. Harris Patent #617.877, 1899).<ref name="ena.com.tr"/> Control systems of the variable stroke wind pumps were mechanical and hydraulic; however, those experiments did not attract the attention of any windpump manufacturer. After experiments with this variable stroke windpump, research focused on wind-electric water pumping systems; no commercial variable stroke windpump exists yet.{{citation needed|date=June 2023}}

===Fluttering windpumps===

Fluttering windpumps have been developed in Canada with a  pump stroke varying strongly with amplitude to absorb all the variable power in the wind and to stop the uniblade from swinging too far beyond horizontal from its vertical mean position. They are much lighter and use less material than multiblade windpumps and can pump effectively in lighter wind regimes.<ref>{{Cite web|url=http://www.econologica.org| title=Econologica}}</ref><ref>Archived at [https://ghostarchive.org/varchive/youtube/20211205/6zIj7LCtX0U Ghostarchive]{{cbignore}} and the [https://web.archive.org/web/20150607101812/https://www.youtube.com/watch?v=6zIj7LCtX0U Wayback Machine]{{cbignore}}: {{cite web| url = https://www.youtube.com/watch?v=6zIj7LCtX0U| title = WING'D MILLS 2013: FLO'Pump and FLUTTER WELL Pump | website=[[YouTube]]| date = 7 December 2013 }}{{cbignore}}</ref>

===Variable stroke windpump===
A Turkish engineer re-designed the variable stroke windpump technology by using modern electronic control equipment. Research began in 2004, with governmental R&D support. The first commercial new generation variable stroke wind pumps have been designed after ten years of R&D. The 30&nbsp;kW variable stroke windpump design includes a Darrieus-type modern wind rotor, counterbalance and regenerative brake technology.<ref>[http://www.ena.com.tr/english.htm ENA Yelkapan Technologies Ltd.]</ref>

===Vertical axis wind pump (VAWP)===
Using a vertical axis wind turbine, the redirection of the turbine torque from horizontal to the vertical axis can be solved, thus creating a basic shaft connection between the turbine and the pump.<ref>[https://www.osti.gov/biblio/7101869-darrieus-wind-turbine-pump-performance-low-lift-irrigation-pumping-final-report Hagen, L. J., and Sharif, M., 1981, “Darrieus Wind Turbine and Pump Performance for Low-Lift Irrigation Pumping,” U.S. Department of Agriculture, Manhattan, KS, Report No. DOE/ARS-3707-20741/81/1.]</ref> The direct connection can produce a more efficient wind-pump. for example, Combining the VAWP system with a high-pressure (HP-VAWP) drip irrigation system can lead, with proper optimization, to two to three times higher efficiency than traditional windpumps.<ref>{{Cite journal| url=https://asmedigitalcollection.asme.org/fluidsengineering/article-abstract/143/5/051204/1095494/High-Pressure-Vertical-Axis-Wind-Pump?redirectedFrom=fulltext| title=Keisar, D., Eilan, B., and Greenblatt, D. (February 8, 2021). "High Pressure Vertical Axis Wind Pump." ASME. J. Fluids Eng. May 2021; 143(5): 051204.| journal=Journal of Fluids Engineering| date=8 February 2021| volume=143| doi=10.1115/1.4049692| last1=Keisar| first1=D.| last2=Eilan| first2=B.| last3=Greenblatt| first3=D.}}</ref>

==Combinations==

===''Tjasker''===
{{Main article|tjasker}}
[[File:Tjasker Sanpoel 04.JPG|thumb|The ''tjasker'']]
In the [[Netherlands]], the ''tjasker'' is a drainage mill with [[windmill sail#Common sails|common sails]] connected to an [[Archimedean screw]]. This is used for pumping water in areas where only a small lift is required. The windshaft sits on a tripod which allows it to pivot. The Archimedean screw lifts water into a collecting ring, where it is drawn off into a ditch at a higher level, thus draining the land.<ref name=Tjasker>{{cite web|url=http://odur.let.rug.nl/polders/boekje/types.htm|title=The types of windmills|publisher=Odur|access-date=2008-05-24}}</ref>

===Thai windpumps===
In Thailand, windpumps are traditionally built on Chinese windpump designs. These pumps are constructed from wire-braced bamboo poles carrying fabric or bamboo-mat sails; a paddle pump or [[waterladder pump]] is fixed to a Thai bladed rotor. They are mainly used in [[Salt pan (evaporation)|salt pans]] where the water lift required is typically less than one meter.<ref>{{cite journal|last=Smulders|first=P.T.|date=January 1996|title=Wind water pumping: the forgotten option|journal=[[Energy for Sustainable Development]]|volume=11|issue=5|page=8 |doi=10.1016/S0973-0826(08)60156-8 |bibcode=1996ESusD...2....8S |url=http://www.energieautark.at/cms/dmdocuments/WindwaterpumpingAfrica.pdf}}</ref>

==See also==
{{div col|colwidth=30em}}
* [[Aermotor Windmill Company]], an American windpump manufacturer
* [[Blade solidity]]
* [[Coil pump]], another frequently used pump<ref>[http://blog.modernmechanix.com/2007/07/27/chinese-windmill-waters-farm/ Coil pump frequently used for windpump construction]</ref>
* [[Loeriesfontein, Northern Cape]], where there is a museum dedicated to water-pumping windmills
* ''[[:nl:Tjasker|Tjasker]]'' on Dutch Wikipedia
* [[Wind turbine]]
* [[Zaanse Schans]]
{{div col end}}

==References==
{{Reflist|refs=
<ref name=isis>{{cite journal|title= Simon Stevin of Bruges (1548-1620)|author=Sarton, George| journal=Isis| volume=21| issue=2| pages=241–303 | year=1934|doi= 10.1086/346851|s2cid=144054163}}</ref>
|2}}

==External links==
{{Commons category|Wind pumps}}
* [http://picasaweb.google.com/andy.bytheway/RestorationOfASouthAfricanWindmill# A detailed photographic record of the restoration of an 8' Stewarts & Lloyds windpump in South Africa]
* [http://www.ironmanwindmill.com/windmill-history.htm History of the Water Pumping Windmill in America.]
* [http://www.ironmanwindmill.com/how-windmills-work.htm How Water Pumping Windmills work.]

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[[Category:Windpumps| ]]
[[Category:Windmills]]
[[Category:Energy harvesting]]
[[Category:Sustainable technologies]]
[[Category:Wind power]]
[[Category:Water supply infrastructure]]
[[Category:Water wells]]