Editing Windpump (section)

==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.