In medieval England rights to waterpower sites were often confined to nobility and clergy, so wind power was an important resource to a new middle class. Lynn White Jr., a specialist in medieval European technology, asserts that the European windmill was an "independent invention " he argues that it is unlikely that the Afghanistan-style horizontal windmill had spread as far west as the Levant during the Crusader period. While it is sometimes argued that crusaders may have been inspired by windmills in the Middle East, this is unlikely since the European vertical windmills were of significantly different design than the horizontal windmills of Afghanistan. The earliest certain reference to a windmill 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 adduced. These early European windmills were sunk post mills. The first windmills in Europe appear in sources dating to the twelfth century. By Lourdes Cardenal - Own work, CC BY-SA 3.0, The vertical windmills of Campo de Criptana were immortalized in chapter VIII of Don Quixote. This public spectacle of wind-powered statues had its private counterpart in the 'Abbasid palaces where automata of various types were predominantly displayed." 3. The "Green Dome of the palace was surmounted by the statue of a horseman carrying a lance that was believed to point toward the enemy. Wind-powered automata are known from the mid-8th century: wind-powered statues that "turned with the wind over the domes of the four gates and the palace complex of the Round City of Baghdad". By 1000 AD, windmills were used to pump seawater for salt-making in China and Sicily. Vertical windmills were later used extensively in Northwestern Europe to grind flour beginning in the 1180s, and many examples still exist. The use of windmills became widespread across the Middle East and Central Asia, and later spread to China and India. These windmills were used to pump water, and in the gristmilling and sugarcane industries. These Panemone windmills were horizontal windmills, which had long vertical driveshafts with six to twelve rectangular sails covered in reed matting or cloth. The first practical windmills were in use in Sistan, a region in Iran and bordering Afghanistan, at least by the 9th century and possibly as early as the mid-to-late 7th century. Wind-powered machines used to grind grain and pump water, the windmill and wind pump, were developed in what are now Iran, Afghanistan and Pakistan by the 9th century. Another early example of a wind-driven wheel was the prayer wheel, which is believed to have been first used in Tibet and China, though there is uncertainty over the date of its first appearance, which could have been either circa 400, the 7th century, or later. His description of a wind-powered organ is not a practical windmill, but was either an early wind-powered toy, or a design concept for a wind-powered machine that may or may not have been a working device, as there is ambiguity in the text and issues with the design. Hero of Alexandria (Heron) in first-century Roman Egypt described what appears to be a wind-driven wheel to power a machine. The Babylonian emperor Hammurabi planned to use wind power for his ambitious irrigation project in the 17th century BC. The use of wind to provide mechanical power came somewhat later in antiquity. Sailboats and sailing ships have been using wind power for at least 5,500 years, and architects have used wind-driven natural ventilation in buildings since similarly ancient times. Heron's wind-powered organ, the earliest machine powered by a windwheel By 2014, over 240,000 commercial-sized wind turbines were operating in the world, producing 4% of the world's electricity. Today wind-powered generators operate in every size range between tiny plants for battery charging at isolated residences, up to near-gigawatt sized offshore wind farms that provide electricity to national electrical networks. Throughout the 20th century parallel paths developed small wind plants suitable for farms or residences, and larger utility-scale wind generators that could be connected to electricity grids for remote use of power. With the development of electric power, wind power found new applications in lighting buildings remote from centrally-generated power. Wind-powered pumps drained the polders of the Netherlands, and in arid regions such as the American mid-west or the Australian outback, wind pumps provided water for livestock and steam engines. Wind power was widely available and not confined to the banks of fast-flowing streams, or later, requiring sources of fuel. For more than two millennia wind-powered machines have ground grain and pumped water. Wind power has been used as long as humans have put sails into the wind.
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