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Essay Subject: History & evolution from 644 A.D.to the 1990s. Purposes, technology, designs, theory, materials, efficiency, wind turbines.... More...

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Paper Abstract: History & evolution from 644 A.D.to the 1990s. Purposes, technology, designs, theory, materials, efficiency, wind turbines. Paper Introduction: Historically, wind energy conversion systems can be considered as one of man's earliest machines. Windmills, according to documentation, were used in Persia as early as 644 A.D. to grind grain (5:9). Mechanically, the Persian windmill was a development of the watermill--an earlier machine used for turning grains into flour--and it looked a little like one turned up on end. A vertical shaft was set in a square tower, with sails set at right angles to the shaft at its top end. The wind passed through slots in the tower on to the sails, allowing the shaft to turn, as well as any machinery set at the bottom end (2:13). Traditionally, this principle travelled with the prisoners of Ghengis Khan to China, where horizontal mills with matting sails, but without the enclosing tower, were used to drive irrigation machinery. The Chinese discovered that if the Text of the Paper: The entire text of the paper is shown below. However, the text is somewhat scrambled. We want to give you as much information as we possibly can about our papers and essays, but we cannot give them away for free. In the text below you will find that while disordered, many of the phrases are essentially intact. From this text you will be able to get a solid sense of the writing style, the concepts addressed, and the sources used in the research paper. earlier machineused for turning grains into end The wind passed through principletravelled with the prisoners of Ghengis Khan to the mill would turn continuouslyso that there was no the twelfth century when almost simultaneously in a village called Weedly in Yorkshire In there is century windmills were more common Possibly the invention of the windmilloccurred quite separately and in that of northern Europe The and Holland were amuch later development appearing most in the s InBritain brick and stone tower sixteenthcentury Drainage and irrigation mills were of the modern windmills for producing electricitywas built obvious when the wind blows on the top of the mill also the drive is carried down to they must be brought to cross on the windshaft and and the bars mortised throughthem which carry the cloth is exerted to push the fast however create enormous stresses or pump efficiently nothing isgained by it These came about by trial wheel set vertically orhorizontally in it thus turning long paddles Eventually itwould have been found of about degrees These sails consisted of a simple or bolted into longitudinal hemlaths to of thestock and tied on at both ends noteasily available and separate whips were made to to be taken out of the windshaft cast iron solved this problem clamps Cast iron provided another means of fixing this method were that sails were independent ofeach other and five six oreven eight sails because it was easier to detail is still in use The bars protrude less at the inner end or heel of the the trailingedge so that the sail can be although they are much more windthat rushes through San Gorgonio Pass Situated in San Gorgonio These mountains create a windtunnel San Francisco San Gorgonio Pass is one of three more than commercial windturbines with a peak the atmosphere because of the varying typography of the earth's As the valleys and mountains heat up andcool off at by the terrain wind speedincreases with height as it flows advantage ofthese high wind speeds Small changes in wind speed For example an increase in are between and mph A wind turbine is windspeed is the maximum speed above which Extremely high winds can cause structural the wings of a plane air passes a three-phase inductiongenerator housed in the turbine's nacelle The proportion speeds A smaller angle operates it atfaster speeds Inside experts the ideal wind turbine would be one currently being done on building agenerator that entire lifetime The mile lifespan of a car are looking toward designing wind turbineswith artificial minimize mechanical loads Wind power is among are as a source of energy are also extremely costly toreplace greatest potential in the United States is as wind turbines that needabout an acre of land each access to utility transmission lines New Mexico and Idaho Other experts think the logic behind developing the solar-powered pumping system was that ofphotovoltaic cells used to convert sunlight into a these pumps willcontinue to function pumping about gallons daily In advanced for of energy Literature Cited Antonoff M Any Van Nostrand ReinholdCompany Nadis S as early as A D to grind grain Mechanically the a square tower with sails set atright turn as well as anymachinery set discovered that if the sails were feathered set at each sail as it passed the slot In Europe the the earliest written record of a windmill is to a windmill in a deed dated In Holland southern Europe and two hundred years before type and the Spanish variety other later illustrations showed simple had in principle the same Sawmills were developed in Holland sea defenses and dams were built so Rural Electrification Act REA provided cheap the axis called a windshaft of gearing drives the millstones and all the subsidiarymachinery Before the wind can strike the sails a tower orsmock mill is turned or winded by various disc described by the revolvingwhips imaginary disc As the wind strikes the and the faster the sails and consequently the go at a speed of at least to revolutions of and expense factors outweigh theadvantages New ways of pushed things infront of it have been simple enough to devise a smallwindmill on from the plane of the stocks The earliest an equal distance on each side of them Later setup without hemlaths Cloth sails were laced that stocks long and strong enough broke it could easily be rot and eventual breakage at this the stockswere fitted into this and the whole think was bolted directly to this without would stay even drier than by using the canister The than four sailsbecame common after this innovation The next development cases there areonly longitudinal boards leading boards in front lines or cords running down bothedges and power developed Today's windmills are designed with California along interstate there are more than windmills spinning windturbines extend for miles to the south toward Mt San state channeling megawatts worth ofharnessable wind power enough to meet of SanFrancisco and Tehachapi Pass about miles northeast of Los billionkilowatt hours of electricity displaces the equivalent of millionbarrels brings cool dense air flowing inland from the ocean into occur as the cool coastal cause the greatest amount of acceleration To turbine If wind speed doubles increase in power generation Most is theminimum speed at which steady speed in order to output aconstant frequency of essential to a turbine's design lift The lift is the force thatpulls the blades theblades to the wind A larger angle wind increases thegenerator increases its forces meet but if the gearbox was eliminated then there grid Most wind turbines operate more hours per year than Maintenance isimportant just as it is for knows about its historical poweroutput It may be able to to less than cents and reliability has increased one thing the fatigue life of a turbine's major components the country is toimprove turbine designs close to population centers These openareas wildlifeto flourish in its natural habitat In greatest wind power potential are pump water forcattle and other uses but a solar-powered pump will needan alternative source of water for energy also works when it is neededmost decide on whether it willbecome more cost effective June Frank D Blowing in the wind Historically wind energy conversion systems can be considered as oneof flour and it looked a little like one turnedup on slots inthe tower on to the China where horizontalmills with matting sails but without need for the enclosing wall and slots to Franceand England the horizontal-axis or a record of a mill at Bishopstone in Sussex innorthern Europe although it would various forms in all those differentplaces The Middle earliest known illustration of an English windmill is likely in the fifteenth toseventeenth century The great Dutch polder millers mostly appear later All threetypes continued to developed before grindingmills in some countries such as Persia and in Denmark Wind machines also played a significant thesails of a windmill This on the windshaft is the brake thebase of the mill and out face the direction from which it isblowing The whole of carry the whips whichbear the sails or shutters as the case may be sail away from it so the sailturns In general ofthrust and friction which a mill could not sustain going too fast Mills with more and error rather than design With a watermill the axle of the wheel Wind that the best angle at which to wooden cross mortisedthrough an axle or windshaft with brace thewhole sail Some of the older types of The sails were reefed by moving them intoward the carry the bars Thesewhips were bolted and The mortise inthe end of the windshaft was always A big casting known as apoll end or stock and sailsto windshaft An iron cross was attached that water would not lie up between make a cross with that many armsthan on thesail's leading edge than on the sail frame or attached torings on rolled and reefed This cuts off the efficient and generate more energy the only opening wherecool air blows in from the that the California Energy Commission estimates is the largestsingle main windfarm locations inCalifornia the other two being generating capacity of approximately megawatts According to the surface As hot air risesand cool different rates they create predictable wind patterns Thesepatterns determine the farther away from the surface Therefore significant changes occur result in largechanges in the kinetic energy produced and wind speedof only two miles per hour from miles per designed to operate under these varying conditionsaccording to no power production is expected damage to the turbine becausegust higher than its over the surfaces of aturbine's airfoil-shaped blades The pressure differential of the wind'senergy being used to generate electricity is the turbine the transmission increases the driveshaft's without a gearbox The transmission is where the can produce electricity at rpm and equals hours of wind turbine operation intelligence Turbines will have adaptive control based onsensing wind the cleanest and most competitive of renewableenergy sources Since there are reasons why they are According to the DOE a major challenge acentralized supplier of electricity Many prime wind sites Being spaced far apart from each other allowsthe wind that would connect them to thenational grid network According to windmill on the farm will be replaced by rangecattle may be excluded from steady flow ofelectricity the solar-powered pump looks conclusion despite its expense wind power is still a viablerenewable speed Pop Sci Jul Beedell S Windmills et al Alternative sources A status report Persian windmill was a development of the watermill an angles to the shaft at its top at the bottom end Traditionally this an angle to the shaft primitive vertical-axis windmills of the Persianswere seen until a rentalnote dated of a windmill in theearliest record is By the end of the thirteenth they would befound in Spain and Asia Minor resembled the Middle Eastern andNorth African windmill rather than post mills The smock mills of Britain basic woodenframework as the English smock mill first appeared at the end of the thatpools and lakes could be drained In the first convenient electricity to farmers A windmill works to state the upon which they are set Inside in the mill In drainage mills at the correct angle to makethem turn means The stocks form a is exactly at right angles to the wind angled sail some of its force called thetangential force windshaft and machinery will turn Sails that turn too thewindshaft per minute in order to grind operating windmills were evolved during the Middle Ages so it would push the paddles of a a tripod using flat sails like sails therefore were set up with a constant pitch the ends ofthe bars were mortised in and out of the bars one each side to take the whole sail were replaced without disturbing its oppositenumber or without having point of great strain The invention of secured and tightened up withwedges stocks being used atall The advantages of iron-cross poll fixing made it possible to put on in design was the common sail which withvariations of of the whip The clothsails are tied pointing lines attached at intervals lower down the same principles as those ofthe past from the force of the Jacinto and formiles to the north toward Mt the residential needs of a city thesize of Angeles Altogether these windfarms have installed of oil Wind originates with the sun's uneven heating of the low-pressure zones of thehot interior deserts and valleys air is funneled throughthe gaps and mountain passes Influenced maximize output wind turbines are designed to take the turbine willproduce eight times as much power turbines in theSan Gorgonio Pass operate when the winds the turbine begins producing power Cut-out Hz so it can tie into a utility's power grid is controlling therotational speed of the blades Similar to in a circular motion to drive captures more wind allowing theturbine to operate at slower wind output which is measured in kilowatts Accordingto some would be a straight shaftinto the generator Research is the average carwill during its an automobile In the future researchers finely adjust its operation parameters tomaximize output and from to percent However efficient windmills is onlyabout five years The components so they last to years Wind technology's of unused land make it easier to install these areas turbines can haveeasier North Dakota Texas Kansas Montana Oklahoma Minnesota Iowa Colorado may now be feasible The them With the declining cost during hot dry weather Even during cloudy days as well as a more Pop Mech Aug Hunt V D Windpower New York man's earliest machines Windmills according to documentation wereused in Persia end A vertical shaft was set in sails allowing the shaft to the enclosing tower were used todrive irrigation machinery The Chinese direct thewind on to the driving side of the Dutch-type windmill came intobeing In England In France there is a reference be another years before they wouldbe common in Eastern windmill has always been very distinctive fromthe northern in theWindmill Psalter c This and many mills although thatchedrather than weatherboarded be built until the mill ceased to be an importantmachine China In Holland they cameinto use after as soon as role inrural America prior to the s when the causes them to turn and thus rotating wheel a big wheel with cogs on itwhich by means to turn a big scoop wheel the body of a post mill or the cap of framework of the sails The are setat an angle to this the greater the sail area the stronger this force willbe indefinitely While amill need to than four sails are morepowerful but the weight stress the principles were obvious and simple Moving water also pushedthings in front of it so it may fix the sails on thestocks would be somewhere about degrees bars mortised through the stocks andsticking out at French mills still carry bars middle like curtains When bigger windmills were built it wasrealized clamped to the stocks and had several advantages Ifone sail a weak point because water could getinto it causing canister was fitted to the end of the windshaft to the windshaft and sail backsor heavier whips were cross and sail back sothe junction to make complicated canisters Windmills with more trailing edge and in many an iron rail The sail has outerlower corner of the sail thus reducing area and the For example northwest of Palm Springs coast to replace the hot desert air the wind resource area in the Altamont Pass about miles east U S Department of Energy the generation of air sinks the difference in atmospheric pressure most ideal location for a windfarm High wind speeds over a ridge or hill and mountainsummits therefore in the powerdelivered by a wind hour mph to mphrepresents a percent its cut-in and cut-out speeds Cut-in speed The turbine's rotor blades must spin at a design speed increase the torsional stresses on thedrivetrain Therefore between the topand bottom surfaces creates aerodynamic controlled by the angle of rateof rpm to match the generator's rpm As the stopping forces and the driving at volts of ACcurrent to go into the utility at mph Each year wind turbinesoperate approximately to hours conditions and on what it costs have dropped from cents per kilowatt-hour not more plentiful in the United States For to producing windturbines that are cost-competitive in more parts of in the GreatPlains and Rocky Mountains are not to rebuild its strength The large spacing also allows the American Wind Energy Association the states in order of asolar panel Historically windmills have been used to wetlands in the future and ranchers like a possible alternative toconventional pumping methods Solar source of energy Future research will New York Charles Scribner's Sons Farewell to windmills USA Today Omni May earlier machineused for turning grains into end The wind passed through principletravelled with the prisoners of Ghengis Khan to the mill would turn continuouslyso that there was no the twelfth century when almost simultaneously in a village called Weedly in Yorkshire In there is century windmills were more common Possibly the invention of the windmilloccurred quite separately and in that of northern Europe The and Holland were amuch later development appearing most in the s InBritain brick and stone tower sixteenthcentury Drainage and irrigation mills were of the modern windmills for producing electricitywas built obvious when the wind blows on the top of the mill also the drive is carried down to they must be brought to cross on the windshaft and and the bars mortised throughthem which carry the cloth is exerted to push the fast however create enormous stresses or pump efficiently nothing isgained by it These came about by trial wheel set vertically orhorizontally in it thus turning long paddles Eventually itwould have been found of about degrees These sails consisted of a simple or bolted into longitudinal hemlaths to of thestock and tied on at both ends noteasily available and separate whips were made to to be taken out of the windshaft cast iron solved this problem clamps Cast iron provided another means of fixing this method were that sails were independent ofeach other and five six oreven eight sails because it was easier to detail is still in use The bars protrude less at the inner end or heel of the the trailingedge so that the sail can be although they are much more windthat rushes through San Gorgonio Pass Situated in San Gorgonio These mountains create a windtunnel San Francisco San Gorgonio Pass is one of three more than commercial windturbines with a peak the atmosphere because of the varying typography of the earth's As the valleys and mountains heat up andcool off at by the terrain wind speedincreases with height as it flows advantage ofthese high wind speeds Small changes in wind speed For example an increase in are between and mph A wind turbine is windspeed is the maximum speed above which Extremely high winds can cause structural the wings of a plane air passes a three-phase inductiongenerator housed in the turbine's nacelle The proportion speeds A smaller angle operates it atfaster speeds Inside experts the ideal wind turbine would be one currently being done on building agenerator that entire lifetime The mile lifespan of a car are looking toward designing wind turbineswith artificial minimize mechanical loads Wind power is among are as a source of energy are also extremely costly toreplace greatest potential in the United States is as wind turbines that needabout an acre of land each access to utility transmission lines New Mexico and Idaho Other experts think the logic behind developing the solar-powered pumping system was that ofphotovoltaic cells used to convert sunlight into a these pumps willcontinue to function pumping about gallons daily In advanced for of energy Literature Cited Antonoff M Any Van Nostrand ReinholdCompany Nadis S as early as A D to grind grain Mechanically the a square tower with sails set atright turn as well as anymachinery set discovered that if the sails were feathered set at each sail as it passed the slot In Europe the the earliest written record of a windmill is to a windmill in a deed dated In Holland southern Europe and two hundred years before type and the Spanish variety other later illustrations showed simple had in principle the same Sawmills were developed in Holland sea defenses and dams were built so Rural Electrification Act REA provided cheap the axis called a windshaft of gearing drives the millstones and all the subsidiarymachinery Before the wind can strike the sails a tower orsmock mill is turned or winded by various disc described by the revolvingwhips imaginary disc As the wind strikes the and the faster the sails and consequently the go at a speed of at least to revolutions of and expense factors outweigh theadvantages New ways of pushed things infront of it have been simple enough to devise a smallwindmill on from the plane of the stocks The earliest an equal distance on each side of them Later setup without hemlaths Cloth sails were laced that stocks long and strong enough broke it could easily be rot and eventual breakage at this the stockswere fitted into this and the whole think was bolted directly to this without would stay even drier than by using the canister The than four sailsbecame common after this innovation The next development cases there areonly longitudinal boards leading boards in front lines or cords running down bothedges and power developed Today's windmills are designed with California along interstate there are more than windmills spinning windturbines extend for miles to the south toward Mt San state channeling megawatts worth ofharnessable wind power enough to meet of SanFrancisco and Tehachapi Pass about miles northeast of Los billionkilowatt hours of electricity displaces the equivalent of millionbarrels brings cool dense air flowing inland from the ocean into occur as the cool coastal cause the greatest amount of acceleration To turbine If wind speed doubles increase in power generation Most is theminimum speed at which steady speed in order to output aconstant frequency of essential to a turbine's design lift The lift is the force thatpulls the blades theblades to the wind A larger angle wind increases thegenerator increases its forces meet but if the gearbox was eliminated then there grid Most wind turbines operate more hours per year than Maintenance isimportant just as it is for knows about its historical poweroutput It may be able to to less than cents and reliability has increased one thing the fatigue life of a turbine's major components the country is toimprove turbine designs close to population centers These openareas wildlifeto flourish in its natural habitat In greatest wind power potential are pump water forcattle and other uses but a solar-powered pump will needan alternative source of water for energy also works when it is neededmost decide on whether it willbecome more cost effective June Frank D Blowing in the wind If this paper is not what you are looking for, you can search again: Search for: or Click here to request an essay written just for you.