Project Report 31

8/12/2019 Project Report 31

1/21

Wind Power

History:

Humans have been using wind power for at least 5,500 years to propel sailboatsand sailing ships, and architects have used wind-driven natural ventilation in

buildings since similarly ancient times. Windmills have been used for irrigationpumping and for milling grain since the 7th century AD.

Wind poweris the conversion ofwindenergy into a useful form of energy, suchas usingwind turbinesto make electricity,wind millsfor mechanical power, wind

pumpsfor pumping water or drainage, or sails to propel ships.

At the end of 2008, worldwide nameplate capacity of wind-powered generatorswas 121.2gigawatts (GW)., which is about 1.5% of worldwide electricity usage;

and is growing rapidly, having doubled in the three years between 2005 and 2008.Several countries have achieved relatively high levels of wind power penetration(with large governmental subsidies), such as 19% of stationary electricity

production inDenmark,13% in SpainandPortugal,and 7% inGermanyand theRepublic of Ireland in 2008. As of May 2009, eighty countries around the worldare using wind power on a commercial basis.

Large-scalewind farmsare connected to theelectric power transmissionnetwork;smaller facilities are used to provide electricity to isolated locations. Utilitycompanies increasingly buy back surplus electricityproduced by small domestic

turbines. Wind energy as a power source is attractive as an alternative to fossilfuels,because it is plentiful,renewable,widely distributed, clean, and produces nogreenhouse gas emissions. However, the construction of wind farms is notuniversally welcomed because of their visual impact and other effects on theenvironment.
http://en.wikipedia.org/wiki/Windhttp://en.wikipedia.org/wiki/Windhttp://en.wikipedia.org/wiki/Windhttp://en.wikipedia.org/wiki/Wind_turbinehttp://en.wikipedia.org/wiki/Wind_turbinehttp://en.wikipedia.org/wiki/Wind_turbinehttp://en.wikipedia.org/wiki/Wind_millhttp://en.wikipedia.org/wiki/Wind_millhttp://en.wikipedia.org/wiki/Wind_millhttp://en.wikipedia.org/wiki/Gigawatthttp://en.wikipedia.org/wiki/Gigawatthttp://en.wikipedia.org/wiki/Gigawatthttp://en.wikipedia.org/wiki/Wind_power_in_Denmarkhttp://en.wikipedia.org/wiki/Wind_power_in_Denmarkhttp://en.wikipedia.org/wiki/Wind_power_in_Denmarkhttp://en.wikipedia.org/wiki/Wind_power_in_Spainhttp://en.wikipedia.org/wiki/Wind_power_in_Spainhttp://en.wikipedia.org/wiki/Wind_power_in_Portugalhttp://en.wikipedia.org/wiki/Wind_power_in_Portugalhttp://en.wikipedia.org/wiki/Wind_power_in_Portugalhttp://en.wikipedia.org/wiki/Wind_power_in_Germanyhttp://en.wikipedia.org/wiki/Wind_power_in_Germanyhttp://en.wikipedia.org/wiki/Wind_power_in_Germanyhttp://en.wikipedia.org/wiki/Wind_power_in_Irelandhttp://en.wikipedia.org/wiki/Wind_power_in_Irelandhttp://en.wikipedia.org/wiki/Wind_farmshttp://en.wikipedia.org/wiki/Wind_farmshttp://en.wikipedia.org/wiki/Wind_farmshttp://en.wikipedia.org/wiki/Electric_power_transmissionhttp://en.wikipedia.org/wiki/Electric_power_transmissionhttp://en.wikipedia.org/wiki/Electric_power_transmissionhttp://en.wikipedia.org/wiki/Net_meteringhttp://en.wikipedia.org/wiki/Net_meteringhttp://en.wikipedia.org/wiki/Fossil_fuelhttp://en.wikipedia.org/wiki/Fossil_fuelhttp://en.wikipedia.org/wiki/Fossil_fuelhttp://en.wikipedia.org/wiki/Renewable_energyhttp://en.wikipedia.org/wiki/Renewable_energyhttp://en.wikipedia.org/wiki/Renewable_energyhttp://en.wikipedia.org/wiki/Greenhouse_gas_emissionshttp://en.wikipedia.org/wiki/Greenhouse_gas_emissionshttp://en.wikipedia.org/wiki/Environmental_effects_of_wind_powerhttp://en.wikipedia.org/wiki/Environmental_effects_of_wind_powerhttp://en.wikipedia.org/wiki/Environmental_effects_of_wind_powerhttp://en.wikipedia.org/wiki/Environmental_effects_of_wind_powerhttp://en.wikipedia.org/wiki/Environmental_effects_of_wind_powerhttp://en.wikipedia.org/wiki/Greenhouse_gas_emissionshttp://en.wikipedia.org/wiki/Renewable_energyhttp://en.wikipedia.org/wiki/Fossil_fuelhttp://en.wikipedia.org/wiki/Fossil_fuelhttp://en.wikipedia.org/wiki/Net_meteringhttp://en.wikipedia.org/wiki/Electric_power_transmissionhttp://en.wikipedia.org/wiki/Wind_farmshttp://en.wikipedia.org/wiki/Wind_power_in_Irelandhttp://en.wikipedia.org/wiki/Wind_power_in_Germanyhttp://en.wikipedia.org/wiki/Wind_power_in_Portugalhttp://en.wikipedia.org/wiki/Wind_power_in_Spainhttp://en.wikipedia.org/wiki/Wind_power_in_Denmarkhttp://en.wikipedia.org/wiki/Gigawatthttp://en.wikipedia.org/wiki/Wind_millhttp://en.wikipedia.org/wiki/Wind_turbinehttp://en.wikipedia.org/wiki/Wind


2/21

Wind power is non-dispatchable,meaning that for economic operation, all of theavailable output must be taken when it is available. Other resources, such ashydropower, and standard load management techniques must be used to matchsupply with demand. The intermittency of wind seldom creates problems whenusing wind power to supply a low proportion of total demand.

Graphical analysis of wind energys variation with wind speed

Distribution of wind speed (red) and energy (blue) for all of 2002 at the Lee Ranchfacility in Colorado. The histogram shows measured data, while the curve is theRayleigh model distribution for the same average wind speed. Energy is the Betzlimit through a 100 m (328 ft) diameter circle facing directly into the wind. Totalenergy for the year through that circle was 15.4gigawatt-hours(GWh).

The Earth is unevenly heated by the sun, such that the poles receive less energyfrom the sun than the equator; along with this, dry land heats up (and cools down)

more quickly than the seas do. The differential heating drives a globalatmosphericconvectionsystem reaching from the Earth's surface to thestratospherewhich actsas a virtual ceiling. Most of the energy stored in these wind movements can befound at high altitudes where continuous wind speeds of over 160 km/h (99 mph)occur. Eventually, the wind energy is converted through friction into diffuse heatthroughout the Earth's surface and the atmosphere.
http://en.wikipedia.org/wiki/Dispatchable_generationhttp://en.wikipedia.org/wiki/Dispatchable_generationhttp://en.wikipedia.org/wiki/Hydropowerhttp://en.wikipedia.org/wiki/Hydropowerhttp://en.wikipedia.org/wiki/Load_managementhttp://en.wikipedia.org/wiki/Load_managementhttp://en.wikipedia.org/wiki/Intermittent_power_sourceshttp://en.wikipedia.org/wiki/Intermittent_power_sourceshttp://en.wikipedia.org/wiki/Gigawatt-hourhttp://en.wikipedia.org/wiki/Gigawatt-hourhttp://en.wikipedia.org/wiki/Gigawatt-hourhttp://en.wikipedia.org/wiki/Convection#Atmospheric_convectionhttp://en.wikipedia.org/wiki/Convection#Atmospheric_convectionhttp://en.wikipedia.org/wiki/Convection#Atmospheric_convectionhttp://en.wikipedia.org/wiki/Convection#Atmospheric_convectionhttp://en.wikipedia.org/wiki/Stratospherehttp://en.wikipedia.org/wiki/Stratospherehttp://en.wikipedia.org/wiki/Stratospherehttp://en.wikipedia.org/wiki/Stratospherehttp://en.wikipedia.org/wiki/Convection#Atmospheric_convectionhttp://en.wikipedia.org/wiki/Convection#Atmospheric_convectionhttp://en.wikipedia.org/wiki/Gigawatt-hourhttp://en.wikipedia.org/wiki/Intermittent_power_sourceshttp://en.wikipedia.org/wiki/Load_managementhttp://en.wikipedia.org/wiki/Hydropowerhttp://en.wikipedia.org/wiki/Dispatchable_generation


3/21

The total amount of economically extractable power available from the wind isconsiderably more than present human power use from all sources. An estimated72terawatt(TW) of wind power on the Earth potentially can be commerciallyviable, compared to about 15 TW average global power consumption from allsources in 2005. Not all the energy of the wind flowing past a given point can berecovered .

Distribution of wind speed

The strength of wind varies, and an average value for a given location does notalone indicate the amount of energy a wind turbine could produce there. To assessthe frequency of wind speeds at a particular location, a probability distributionfunction is often fit to the observed data. Different locations will have differentwind speed distributions. TheWeibullmodel closely mirrors the actual distributionof hourly wind speeds at many locations. The Weibull factor is often close to 2 andtherefore aRayleigh distributioncan be used as a less accurate, but simpler model.

Because so much power is generated by higher wind speed, much of the energycomes in short bursts. The 2002 Lee Ranch sample is telling; half of the energyavailable arrived in just 15% of the operating time. The consequence is that windenergy from a particular turbine or wind farm does not have as consistent an outputas fuel-fired power plants; utilities that use wind power provide power fromstarting existing generation for times when the wind is weak thus wind power is

primarily a fuel saver rather than a capacity saver. Making wind power moreconsistent requires that various existing technologies and methods be extended, in

particular the use of stronger inter-regional transmission lines to link widelydistributed wind farms. Problems of variability are addressed by grid energystorage, batteries, pumped-storage hydroelectricity and energy demandmanagement.

Uses of Wind Power

Electricity generation

Typical components of a wind turbine (gearbox, rotor shaft and brake assembly)being lifted into position
http://en.wikipedia.org/wiki/Terawatthttp://en.wikipedia.org/wiki/Terawatthttp://en.wikipedia.org/wiki/Terawatthttp://en.wikipedia.org/wiki/World_energy_resources_and_consumptionhttp://en.wikipedia.org/wiki/World_energy_resources_and_consumptionhttp://en.wikipedia.org/wiki/Weibull_distributionhttp://en.wikipedia.org/wiki/Weibull_distributionhttp://en.wikipedia.org/wiki/Weibull_distributionhttp://en.wikipedia.org/wiki/Rayleigh_distributionhttp://en.wikipedia.org/wiki/Rayleigh_distributionhttp://en.wikipedia.org/wiki/Rayleigh_distributionhttp://en.wikipedia.org/wiki/Grid_energy_storagehttp://en.wikipedia.org/wiki/Grid_energy_storagehttp://en.wikipedia.org/wiki/Grid_energy_storagehttp://en.wikipedia.org/wiki/Battery_(electricity)http://en.wikipedia.org/wiki/Battery_(electricity)http://en.wikipedia.org/wiki/Pumped-storage_hydroelectricityhttp://en.wikipedia.org/wiki/Pumped-storage_hydroelectricityhttp://en.wikipedia.org/wiki/Energy_demand_managementhttp://en.wikipedia.org/wiki/Energy_demand_managementhttp://en.wikipedia.org/wiki/Energy_demand_managementhttp://en.wikipedia.org/wiki/Energy_demand_managementhttp://en.wikipedia.org/wiki/Energy_demand_managementhttp://en.wikipedia.org/wiki/Pumped-storage_hydroelectricityhttp://en.wikipedia.org/wiki/Battery_(electricity)http://en.wikipedia.org/wiki/Grid_energy_storagehttp://en.wikipedia.org/wiki/Grid_energy_storagehttp://en.wikipedia.org/wiki/Rayleigh_distributionhttp://en.wikipedia.org/wiki/Weibull_distributionhttp://en.wikipedia.org/wiki/World_energy_resources_and_consumptionhttp://en.wikipedia.org/wiki/Terawatt


4/21

In a wind farm, individual turbines are interconnected with a medium voltage(often 34.5 kV), power collection system and communications network. At asubstation, this medium-voltage electrical current is increased in voltage with atransformerfor connection to the high voltageelectric power transmissionsystem.

The surplus power produced by domestic micro generators can, in some

jurisdictions, be fed into the network and sold to the utility company, producing aretail credit for the micro generators' owners to offset their energy costs.

Grid management

Induction generators, often used for wind power, require reactive power forexcitationsosubstationsused in wind-power collection systems include substantialcapacitorbanks for power factor correction. Different types of wind turbinegenerators behave differently during transmission grid disturbances, so extensivemodellingof the dynamic electromechanical characteristics of a new wind farm is

required by transmission system operators to ensure predictable stable behaviourduring system faults .In particular, induction generators cannot support the systemvoltage during faults, unlike steam or hydro turbine-driven synchronousgenerators. Doubly-fed machineswind turbines with solid-state converters

between the turbine generator and the collector systemgenerally have moredesirable properties for grid interconnection. Transmission systems operators willsupply a wind farm developer with a grid code to specify the requirements forinterconnection to the transmission grid. This will includepower factor,constancyof frequency and dynamic behaviour of the wind farm turbines during a system

fault.

Capacity factor

Worldwide installed capacity 19972008, with projection 200913 based on anexponential fit. Data source:WWEA

Since wind speed is not constant, awind farm's annual energy production is neveras much as the sum of the generator nameplate ratings multiplied by the total hoursin a year. The ratio of actual productivity in a year to this theoretical maximum is
http://en.wikipedia.org/wiki/Wind_farmhttp://en.wikipedia.org/wiki/Wind_farmhttp://en.wikipedia.org/wiki/Transformerhttp://en.wikipedia.org/wiki/Transformerhttp://en.wikipedia.org/wiki/Electric_power_transmissionhttp://en.wikipedia.org/wiki/Electric_power_transmissionhttp://en.wikipedia.org/wiki/Electric_power_transmissionhttp://en.wikipedia.org/wiki/Induction_generatorhttp://en.wikipedia.org/wiki/Induction_generatorhttp://en.wikipedia.org/wiki/Reactive_powerhttp://en.wikipedia.org/wiki/Reactive_powerhttp://en.wikipedia.org/wiki/Excitation_(magnetic)http://en.wikipedia.org/wiki/Excitation_(magnetic)http://en.wikipedia.org/wiki/Electrical_substationhttp://en.wikipedia.org/wiki/Electrical_substationhttp://en.wikipedia.org/wiki/Electrical_substationhttp://en.wikipedia.org/wiki/Capacitorhttp://en.wikipedia.org/wiki/Capacitorhttp://en.wikipedia.org/wiki/Power_factor_correctionhttp://en.wikipedia.org/wiki/Power_factor_correctionhttp://en.wikipedia.org/wiki/Wind_energy_softwarehttp://en.wikipedia.org/wiki/Wind_energy_softwarehttp://en.wikipedia.org/wiki/Wind_energy_softwarehttp://en.wikipedia.org/wiki/Doubly-fed_electric_machinehttp://en.wikipedia.org/wiki/Power_factorhttp://en.wikipedia.org/wiki/Power_factorhttp://en.wikipedia.org/wiki/Power_factorhttp://en.wikipedia.org/wiki/Utility_frequencyhttp://en.wikipedia.org/wiki/Utility_frequencyhttp://www.wwindea.org/http://www.wwindea.org/http://www.wwindea.org/http://en.wikipedia.org/wiki/Wind_farmhttp://en.wikipedia.org/wiki/Wind_farmhttp://en.wikipedia.org/wiki/Wind_farmhttp://en.wikipedia.org/wiki/File:WorldWindPower2008.pnghttp://en.wikipedia.org/wiki/Wind_farmhttp://www.wwindea.org/http://en.wikipedia.org/wiki/Utility_frequencyhttp://en.wikipedia.org/wiki/Power_factorhttp://en.wikipedia.org/wiki/Doubly-fed_electric_machinehttp://en.wikipedia.org/wiki/Wind_energy_softwarehttp://en.wikipedia.org/wiki/Wind_energy_softwarehttp://en.wikipedia.org/wiki/Power_factor_correctionhttp://en.wikipedia.org/wiki/Capacitorhttp://en.wikipedia.org/wiki/Electrical_substationhttp://en.wikipedia.org/wiki/Excitation_(magnetic)http://en.wikipedia.org/wiki/Reactive_powerhttp://en.wikipedia.org/wiki/Induction_generatorhttp://en.wikipedia.org/wiki/Electric_power_transmissionhttp://en.wikipedia.org/wiki/Transformerhttp://en.wikipedia.org/wiki/Wind_farm


5/21

called thecapacity factor.Typical capacity factors are 2040%, with values at theupper end of the range in particularly favourable sites.

For example, a 1 MW turbine with a capacity factor of 35% will not produce8,760 MWh in a year (1 24 365), but only 1 0.35 24 365 = 3,066 MWh,averaging to 0.35 MW. Online data is available for some locations and the capacity

factor can be calculated from the yearly output.

Unlike fueled generating plants, the capacity factor is limited by the inherentproperties of wind. Capacity factors of other types of power plant are based mostlyon fuel cost, with a small amount of downtime for maintenance. Nuclear plantshave low incremental fuel cost, and so are run at full output and achieve a 90%capacity factor. Plants with higher fuel cost are throttled back to follow load.Gasturbineplants usingnatural gasas fuel may be very expensive to operate and may

be run only to meetpeak power demand.A gas turbine plant may have an annualcapacity factor of 525% due to relatively high energy production cost.

According to a 2007 Stanford University study published in the Journal of AppliedMeteorology and Climatology, interconnecting ten or more wind farms can allowan average of 33% of the total energy produced to be used as reliable, baseloadelectric power, as long as minimum criteria are met for wind speed and turbineheight.

In a 2008 study released by the U.S. Department of Energy's Office of EnergyEfficiency and Renewable Energy, the capacity factor achieved by the windturbine fleet is shown to be increasing as the technology improves. The capacity

factor achieved by new wind turbines in 2004 and 2005 reached 36%.

Penetration

Wind energy "penetration" refers to the fraction of energy produced by windcompared with the total available generation capacity. There is no generallyaccepted "maximum" level of wind penetration. The limit for a particular grid willdepend on the existing generating plants, pricing mechanisms, capacity for storageor demand management, and other factors. An interconnected electricity grid will

already include reserve generating and transmission capacity to allow forequipment failures; this reserve capacity can also serve to regulate for the varyingpower generation by wind plants. Studies have indicated that 20% of the totalelectrical energy consumption may be incorporated with minimal difficulty. Thesestudies have been for locations with geographically dispersed wind farms, somedegree of dispatchable energy, or hydropower with storage capacity, demandmanagement, and interconnection to a large grid area export of electricity whenneeded. Beyond this level, there are few technical limits, but the economic
http://en.wikipedia.org/wiki/Capacity_factorhttp://en.wikipedia.org/wiki/Capacity_factorhttp://en.wikipedia.org/wiki/Capacity_factorhttp://en.wikipedia.org/wiki/Nuclear_Powerhttp://en.wikipedia.org/wiki/Nuclear_Powerhttp://en.wikipedia.org/wiki/Load_following_power_planthttp://en.wikipedia.org/wiki/Load_following_power_planthttp://en.wikipedia.org/wiki/Load_following_power_planthttp://en.wikipedia.org/wiki/Gas_turbinehttp://en.wikipedia.org/wiki/Gas_turbinehttp://en.wikipedia.org/wiki/Gas_turbinehttp://en.wikipedia.org/wiki/Gas_turbinehttp://en.wikipedia.org/wiki/Natural_gashttp://en.wikipedia.org/wiki/Natural_gashttp://en.wikipedia.org/wiki/Natural_gashttp://en.wikipedia.org/wiki/Peaking_power_planthttp://en.wikipedia.org/wiki/Peaking_power_planthttp://en.wikipedia.org/wiki/Peaking_power_planthttp://en.wikipedia.org/wiki/Baseload_powerhttp://en.wikipedia.org/wiki/Baseload_powerhttp://en.wikipedia.org/wiki/Baseload_powerhttp://en.wikipedia.org/wiki/Baseload_powerhttp://en.wikipedia.org/wiki/Baseload_powerhttp://en.wikipedia.org/wiki/Peaking_power_planthttp://en.wikipedia.org/wiki/Natural_gashttp://en.wikipedia.org/wiki/Gas_turbinehttp://en.wikipedia.org/wiki/Gas_turbinehttp://en.wikipedia.org/wiki/Load_following_power_planthttp://en.wikipedia.org/wiki/Nuclear_Powerhttp://en.wikipedia.org/wiki/Capacity_factor


6/21

implications become more significant. Electrical utilities continue to study theeffects of large (20% or more) scale penetration of wind generation on systemstability and economics.

At present, a few grid systems have penetration of wind energy above 5%:Denmark (values over 19%), Spain and Portugal (values over 11%), Germany and

the Republic of Ireland (values over 6%). For instance, in the morning hours of 8November 2009, wind energy produced covered more than half the electricitydemand in Spain, setting a new record, and without problems for the network. TheDanish grid is heavily interconnected to the European electrical grid, and it hassolved grid management problems by exporting almost half of its wind power to

Norway. The correlation between electricity export and wind power production isvery strong.

Intermittency and penetration limits

Electricity generated from wind power can be highly variable at several differenttimescales: from hour to hour, daily, and seasonally. Annual variation also exists,

but is not as significant. Related to variability is the short-term (hourly or daily)predictability of wind plant output. Like other electricity sources, wind energymust be "scheduled". Wind power forecasting methods are used, but predictabilityof wind plant output remains low for short-term operation.

Because instantaneous electrical generation and consumption must remain inbalance to maintain grid stability, this variability can present substantial challengesto incorporating large amounts of wind power into a grid system.Intermittencyandthe non-dispatchable nature of wind energy production can raise costs forregulation, incremental operating reserve, and (at high penetration levels) couldrequire an increase in the already existing energy demand management, loadshedding, or storage solutions or system interconnection with HVDC cables. Atlow levels of wind penetration, fluctuations in load and allowance for failure oflarge generating units requires reserve capacity that can also regulate for variabilityof wind generation. Wind power can be replaced by other power stations duringlow wind periods. Transmission networks must already cope with outages ofgeneration plant and daily changes in electrical demand. Systems with large wind

capacity components may need more spinning reserve (plants operating at less thanfull load).

Pumped-storage hydroelectricity or other forms of grid energy storage can storeenergy developed by high-wind periods and release it when needed. Stored energyincreases the economic value of wind energy since it can be shifted to displacehigher cost generation during peak demand periods. The potential revenue from
http://en.wikipedia.org/wiki/Intermittent_power_sourceshttp://en.wikipedia.org/wiki/Intermittent_power_sourceshttp://en.wikipedia.org/wiki/Intermittent_power_sourceshttp://en.wikipedia.org/wiki/Intermittent_power_sources#Terminologyhttp://en.wikipedia.org/wiki/Intermittent_power_sources#Terminologyhttp://en.wikipedia.org/wiki/Intermittent_power_sources#Terminologyhttp://en.wikipedia.org/wiki/Operating_reservehttp://en.wikipedia.org/wiki/Operating_reservehttp://en.wikipedia.org/wiki/Energy_demand_managementhttp://en.wikipedia.org/wiki/Energy_demand_managementhttp://en.wikipedia.org/wiki/Load_sheddinghttp://en.wikipedia.org/wiki/Load_sheddinghttp://en.wikipedia.org/wiki/Load_sheddinghttp://en.wikipedia.org/wiki/High-voltage_direct_currenthttp://en.wikipedia.org/wiki/High-voltage_direct_currenthttp://en.wikipedia.org/wiki/Pumped-storage_hydroelectricityhttp://en.wikipedia.org/wiki/Pumped-storage_hydroelectricityhttp://en.wikipedia.org/wiki/Grid_energy_storagehttp://en.wikipedia.org/wiki/Grid_energy_storagehttp://en.wikipedia.org/wiki/Grid_energy_storagehttp://en.wikipedia.org/wiki/Pumped-storage_hydroelectricityhttp://en.wikipedia.org/wiki/High-voltage_direct_currenthttp://en.wikipedia.org/wiki/Load_sheddinghttp://en.wikipedia.org/wiki/Load_sheddinghttp://en.wikipedia.org/wiki/Energy_demand_managementhttp://en.wikipedia.org/wiki/Operating_reservehttp://en.wikipedia.org/wiki/Intermittent_power_sources#Terminologyhttp://en.wikipedia.org/wiki/Intermittent_power_sources


7/21

thisarbitragecan offset the cost and losses of storage; the cost of storage may add25% to the cost of any wind energy stored, but it is not envisaged that this wouldapply to a large proportion of wind energy generated. The 2 GW Dinorwig pumpedstorage plant in Wales evens out electrical demand peaks, and allows base-loadsuppliers to run their plant more efficiently. Although pumped storage powersystems are only about 75% efficient, and have high installation costs, their low

running costs and ability to reduce the required electrical base-load can save bothfuel and total electrical generation costs.

In particular geographic regions, peak wind speeds may not coincide with peakdemand for electrical power. In the US states ofCaliforniaandTexas,for example,hot days in summer may have low wind speed and high electrical demand due toair conditioning.Some utilities subsidize the purchase of geothermal heat pumps

by their customers, to reduce electricity demand during the summer months bymaking air conditioning up to 70% more efficient;[ widespread adoption of thistechnology would better match electricity demand to wind availability in areas

with hot summers and low summer winds.

Another option is to interconnect widely dispersed geographic areas with anHVDC "Super grid". In the USA it is estimated that to upgrade the transmissionsystem to take in planned or potential renewables would cost at least $60 billion.Total annual US power consumption in 2006 was 4 thousand billion kWh. Overan asset life of 40 years and low cost utility investment grade funding, the cost of$60 billion investment would be about 5% p.a. (i.e. $3 billion p.a.) Dividing bytotal power used gives an increased unit cost of around $3,000,000,000 100 /

4,000 1 exp9 = 0.075 cent/kWh.

In the UK, demand for electricity is higher in winter than in summer, and so arewind speeds.Solar powertends to be complementary to wind.

On daily to weekly timescales, high pressure areas tend to bring clear skies andlow surface winds, whereaslow pressure areastend to be windier and cloudier. Onseasonal timescales, solar energy typically peaks in summer, whereas in manyareas wind energy is lower in summer and higher in winter.

Thus the intermittencies of wind and solar power tend to cancel each othersomewhat. A demonstration project at the Massachusetts Maritime Academyshows the effect. The Institute for Solar Energy Supply Technology of theUniversity of Kasselpilot-tested a combined power plant linking solar, wind,

biogas and hydrostorage to provide load-following power around the clock,entirely from renewable sources.
http://en.wikipedia.org/wiki/Arbitragehttp://en.wikipedia.org/wiki/Arbitragehttp://en.wikipedia.org/wiki/Arbitragehttp://en.wikipedia.org/wiki/Californiahttp://en.wikipedia.org/wiki/Californiahttp://en.wikipedia.org/wiki/Californiahttp://en.wikipedia.org/wiki/Texashttp://en.wikipedia.org/wiki/Texashttp://en.wikipedia.org/wiki/Texashttp://en.wikipedia.org/wiki/Air_conditioninghttp://en.wikipedia.org/wiki/Air_conditioninghttp://en.wikipedia.org/wiki/Geothermal_heat_pumphttp://en.wikipedia.org/wiki/Geothermal_heat_pumphttp://en.wikipedia.org/wiki/Super_gridhttp://en.wikipedia.org/wiki/Solar_powerhttp://en.wikipedia.org/wiki/Solar_powerhttp://en.wikipedia.org/wiki/Solar_powerhttp://en.wikipedia.org/wiki/High_pressure_areahttp://en.wikipedia.org/wiki/High_pressure_areahttp://en.wikipedia.org/wiki/Low_pressure_areahttp://en.wikipedia.org/wiki/Low_pressure_areahttp://en.wikipedia.org/wiki/Low_pressure_areahttp://en.wikipedia.org/wiki/Massachusetts_Maritime_Academyhttp://en.wikipedia.org/wiki/Massachusetts_Maritime_Academyhttp://en.wikipedia.org/wiki/University_of_Kasselhttp://en.wikipedia.org/wiki/University_of_Kasselhttp://en.wikipedia.org/wiki/Virtual_power_planthttp://en.wikipedia.org/wiki/Virtual_power_planthttp://en.wikipedia.org/wiki/Biogashttp://en.wikipedia.org/wiki/Biogashttp://en.wikipedia.org/wiki/Pumped-storage_hydroelectricityhttp://en.wikipedia.org/wiki/Pumped-storage_hydroelectricityhttp://en.wikipedia.org/wiki/Pumped-storage_hydroelectricityhttp://en.wikipedia.org/wiki/Biogashttp://en.wikipedia.org/wiki/Virtual_power_planthttp://en.wikipedia.org/wiki/University_of_Kasselhttp://en.wikipedia.org/wiki/Massachusetts_Maritime_Academyhttp://en.wikipedia.org/wiki/Low_pressure_areahttp://en.wikipedia.org/wiki/High_pressure_areahttp://en.wikipedia.org/wiki/Solar_powerhttp://en.wikipedia.org/wiki/Super_gridhttp://en.wikipedia.org/wiki/Geothermal_heat_pumphttp://en.wikipedia.org/wiki/Air_conditioninghttp://en.wikipedia.org/wiki/Texashttp://en.wikipedia.org/wiki/Californiahttp://en.wikipedia.org/wiki/Arbitrage


8/21


9/21

could be retired when such wind is added without affecting system security orrobustness. But the precise value is irrelevant since the main value of wind (in theUK, worth 5 times the capacity credit value is its fuel and CO2 savings.

Turbine placement

Good selection of a wind turbine site is critical to economic development of windpower. Aside from the availability of wind itself, other factors include theavailability of transmission lines, value of energy to be produced, cost of landacquisition, land use considerations, and environmental impact of construction andoperations. Off-shore locations may offset their higher construction cost withhigher annual load factors, thereby reducing cost of energy produced. Wind farmdesigners use specializedwind energy softwareapplications to evaluate the impactof these issues on a given wind farm design.

Wind power density(WPD) is a calculation of the effective power of the wind at a

particular location. A map showing the distribution of wind power density is a firststep in identifying possible locations for wind turbines. In the United States, the

National Renewable Energy Laboratory classifies wind power density intoascending classes. The larger the WPD at a location, the higher it is rated by class.Wind power classes 3 (300400 W/m2at 50 m altitude) to 7 (8002000 W/m2 at50 m altitude) are generally considered suitable for wind power development.There are 625,000 km2in the contiguous United States that have class 3 or higherwind resources and which are within 10 km of electric transmission lines. If thisarea is fully utilized for wind power, it would produce power at the average

continuous equivalent rate of 734 GWe. For comparison, in 2007 the US consumedelectricity at an average rate of 474 GW, from a total generating capacity of1,088 GW.

Wind power usage

Installed windpower capacity (MW)[1]

# Nation 2005 2006 2007 2008 2009

-European

Union40,722 48,122 56,614 65,255

1United

9,149 11,603 16,819 25,170 33,170
http://en.wikipedia.org/wiki/List_of_offshore_wind_farmshttp://en.wikipedia.org/wiki/List_of_offshore_wind_farmshttp://en.wikipedia.org/wiki/Wind_energy_softwarehttp://en.wikipedia.org/wiki/Wind_energy_softwarehttp://en.wikipedia.org/wiki/Wind_energy_softwarehttp://en.wikipedia.org/wiki/Wind_profile_power_law#Wind_power_densityhttp://en.wikipedia.org/wiki/Wind_profile_power_law#Wind_power_densityhttp://en.wikipedia.org/wiki/National_Renewable_Energy_Laboratoryhttp://en.wikipedia.org/wiki/National_Renewable_Energy_Laboratoryhttp://en.wikipedia.org/wiki/Wind_power#cite_note-wwea-0http://en.wikipedia.org/wiki/Wind_power#cite_note-wwea-0http://en.wikipedia.org/wiki/Wind_power#cite_note-wwea-0http://en.wikipedia.org/wiki/Wind_power_in_the_European_Unionhttp://en.wikipedia.org/wiki/Wind_power_in_the_European_Unionhttp://en.wikipedia.org/wiki/Wind_power_in_the_European_Unionhttp://en.wikipedia.org/wiki/Wind_power_in_the_European_Unionhttp://en.wikipedia.org/wiki/Wind_power_in_the_United_Stateshttp://en.wikipedia.org/wiki/Wind_power_in_the_United_Stateshttp://en.wikipedia.org/wiki/United_Stateshttp://en.wikipedia.org/wiki/European_Unionhttp://en.wikipedia.org/wiki/United_Stateshttp://en.wikipedia.org/wiki/European_Unionhttp://en.wikipedia.org/wiki/Wind_power_in_the_United_Stateshttp://en.wikipedia.org/wiki/Wind_power_in_the_European_Unionhttp://en.wikipedia.org/wiki/Wind_power_in_the_European_Unionhttp://d/manuf%20proj/Wind%20power%20-%20Wikipedia,%20the%20free%20encyclopedia.htmhttp://d/manuf%20proj/Wind%20power%20-%20Wikipedia,%20the%20free%20encyclopedia.htmhttp://d/manuf%20proj/Wind%20power%20-%20Wikipedia,%20the%20free%20encyclopedia.htmhttp://d/manuf%20proj/Wind%20power%20-%20Wikipedia,%20the%20free%20encyclopedia.htmhttp://d/manuf%20proj/Wind%20power%20-%20Wikipedia,%20the%20free%20encyclopedia.htmhttp://d/manuf%20proj/Wind%20power%20-%20Wikipedia,%20the%20free%20encyclopedia.htmhttp://d/manuf%20proj/Wind%20power%20-%20Wikipedia,%20the%20free%20encyclopedia.htmhttp://en.wikipedia.org/wiki/Wind_power#cite_note-wwea-0http://en.wikipedia.org/wiki/National_Renewable_Energy_Laboratoryhttp://en.wikipedia.org/wiki/Wind_profile_power_law#Wind_power_densityhttp://en.wikipedia.org/wiki/Wind_energy_softwarehttp://en.wikipedia.org/wiki/List_of_offshore_wind_farms


10/21

States

2 Germany 18,428 20,622 22,247 23,903 25,000

3 China 1,266 2,599 5,912 12,210 22,500

4 Spain 10,028 11,630 15,145 16,740 18,263

5 India 4,430 6,270 7,850 9,587 11,587

Windmill for pumping the water out

Fig. A windmill in function as a water pump

Background of wind mill water pumps

In the United States, the development of the "water-pumping windmill" was themajor factor in allowing the farming and ranching of vast areas otherwise devoidof readily accessible water. Windpumps contributed to the expansion of railtransport systems throughout the world, by pumping water from water wells for thesteam locomotives.

How windmills work?

While they are simple in operation, they incorporate many details that arenecessary for proper operation, protection from storms, providing correctlubrication of the moving parts and ultimately a long and trouble free life.We will describe and attempt to explain the operation of the major
http://en.wikipedia.org/wiki/Wind_power_in_the_United_Stateshttp://en.wikipedia.org/wiki/Wind_power_in_the_United_Stateshttp://en.wikipedia.org/wiki/Wind_power_in_Germanyhttp://en.wikipedia.org/wiki/Wind_power_in_Germanyhttp://en.wikipedia.org/wiki/People's_Republic_of_Chinahttp://en.wikipedia.org/wiki/People's_Republic_of_Chinahttp://en.wikipedia.org/wiki/Wind_power_in_Spainhttp://en.wikipedia.org/wiki/Wind_power_in_Spainhttp://en.wikipedia.org/wiki/Wind_power_in_Spainhttp://en.wikipedia.org/wiki/Wind_power_in_Indiahttp://en.wikipedia.org/wiki/Wind_power_in_Indiahttp://en.wikipedia.org/wiki/Wind_power_in_Indiahttp://en.wikipedia.org/wiki/Windpumpshttp://en.wikipedia.org/wiki/Windpumpshttp://en.wikipedia.org/wiki/Steam_locomotivehttp://en.wikipedia.org/wiki/Steam_locomotivehttp://en.wikipedia.org/wiki/Indiahttp://en.wikipedia.org/wiki/Spainhttp://en.wikipedia.org/wiki/Germanyhttp://en.wikipedia.org/wiki/Indiahttp://en.wikipedia.org/wiki/Spainhttp://en.wikipedia.org/wiki/Germanyhttp://en.wikipedia.org/wiki/Indiahttp://en.wikipedia.org/wiki/Spainhttp://en.wikipedia.org/wiki/Germanyhttp://en.wikipedia.org/wiki/Indiahttp://en.wikipedia.org/wiki/Spainhttp://en.wikipedia.org/wiki/Germanyhttp://en.wikipedia.org/wiki/Steam_locomotivehttp://en.wikipedia.org/wiki/Windpumpshttp://en.wikipedia.org/wiki/Wind_power_in_Indiahttp://en.wikipedia.org/wiki/Wind_power_in_Spainhttp://en.wikipedia.org/wiki/People's_Republic_of_Chinahttp://en.wikipedia.org/wiki/People's_Republic_of_Chinahttp://en.wikipedia.org/wiki/Wind_power_in_Germanyhttp://en.wikipedia.org/wiki/Wind_power_in_the_United_States


11/21

components here.

Two or more heavy steel bands support the sails and maintain properalignment. They also provide strength to hold the wind wheel together instrong winds, when the centrifugal forces can be great. Strong steel Wheel

Arms connect to the Hub to hold the Bands in alignment and provide

strength like the spokes in a bicycle wheel.

WINDMILL PUMP

The windmill pump is the device that actually pumps the water. Water ispumped to the surface when the pump rod raises the piston. The pistoncheck valve closes and holds the water above the piston. As the pistonrises, water is moved up the pipe towards the surface. Water is also drawninto the lower section of the pump cylinder through a screen and the lowercheck valve. When the pump rod reverses and begins to descend, the

lower check valve closes and the piston check valve opens allowing thewater in the cylinder to pass through the piston check valve and becometrapped above the piston when the check valve closes. This cycle isconstantly repeated as the wind wheel turns, operating the reciprocatingmechanism in the gearbox, which operates the pump rod and pump.


12/21

Deep well pumps, connect to the bottom of a string of pipe, which issupported at the surface of the ground in the center of the windmill tower.The Pump Rod that operates the piston passes through the full length ofpipe all the way to the surface and connects with the pump rod in thewindmill gearbox. The pumping cycle is slow and therefore friction is verylow as opposed to rotary pumps that must operate at a much higher speed

and hence suffer from significant losses due to friction. It is also possible tolocate the pump some distance from the windmill and operate it with cablesor other mechanism to pump water from a river, lake, pond, spring or evena water tank used to collect and hold water. It is always best to locate thepump cylinder below the lowest level of water for dependable operation.

The best windmill pumps for deep well use are made of stainless steel,alloy steel with proprietary ultra hard linings or with brass or bronze bodies

or liners. They allow the pump rod to be disconnected and easily removed,without having to remove th well pipe. Many pumps are designed to allowthe piston to be lowered and remove rotated, causing the bottom of thepiston to connect with the top of the lower check valve. Both can then belifted to the surface for servicing without any need to remove the pipe. Thisis a great convenience when servicing deep well pumps. Windmill pumpcan provide standard or special pumps of all sizes and types for everypumping application.

The piston moves up and down with each stroke.This process literally lifts the water to the surface.

Processes Used

Casting


13/21

Casting iron in a sand mold

Casting is a manufacturingprocess by which a liquid material is usually pouredinto amold,which contains a hollow cavity of the desired shape, and then allowedto solidify. The solidified part is also known as a casting, which is ejected or

broken out of the mold to complete the process. Casting materials are usuallymetals or various cold setting materials that cure after mixing two or morecomponents together; examples are epoxy, concrete,plaster and clay. Casting ismost often used for making complex shapes that would be otherwise difficult oruneconomical to make by other methods.Casting is a 6000 year old process.Theoldest surviving casting is a copper frog from 3200 BC.

There are two main types of sand used for molding. Green sand is a mixture ofsilica sand, clay, moisture and other additives. The air setmethod uses dry sand

bonded to materials other than clay, using a fast curing adhesive.The latter mayalso be referred to as no bake mold casting. When these are used, they are
http://en.wikipedia.org/wiki/Manufacturinghttp://en.wikipedia.org/wiki/Manufacturinghttp://en.wikipedia.org/wiki/Mold_(manufacturing)http://en.wikipedia.org/wiki/Mold_(manufacturing)http://en.wikipedia.org/wiki/Mold_(manufacturing)http://en.wikipedia.org/wiki/Curing_(chemistry)http://en.wikipedia.org/wiki/Curing_(chemistry)http://en.wikipedia.org/wiki/Epoxyhttp://en.wikipedia.org/wiki/Epoxyhttp://en.wikipedia.org/wiki/Concretehttp://en.wikipedia.org/wiki/Concretehttp://en.wikipedia.org/wiki/Plasterhttp://en.wikipedia.org/wiki/Plasterhttp://en.wikipedia.org/wiki/Clayhttp://en.wikipedia.org/wiki/Clayhttp://en.wikipedia.org/wiki/Green_sandhttp://en.wikipedia.org/wiki/Green_sandhttp://en.wikipedia.org/wiki/Adhesivehttp://en.wikipedia.org/wiki/Adhesivehttp://en.wikipedia.org/wiki/No_bake_mold_castinghttp://en.wikipedia.org/wiki/No_bake_mold_castinghttp://en.wikipedia.org/wiki/File:Haandform-e.pnghttp://en.wikipedia.org/wiki/File:Casting.jpghttp://en.wikipedia.org/wiki/File:Haandform-e.pnghttp://en.wikipedia.org/wiki/File:Casting.jpghttp://en.wikipedia.org/wiki/No_bake_mold_castinghttp://en.wikipedia.org/wiki/Adhesivehttp://en.wikipedia.org/wiki/Green_sandhttp://en.wikipedia.org/wiki/Clayhttp://en.wikipedia.org/wiki/Plasterhttp://en.wikipedia.org/wiki/Concretehttp://en.wikipedia.org/wiki/Epoxyhttp://en.wikipedia.org/wiki/Curing_(chemistry)http://en.wikipedia.org/wiki/Mold_(manufacturing)http://en.wikipedia.org/wiki/Manufacturing


14/21

collectively called "air set" sand castings to distinguish these from "green sand"castings. Two types of molding sand are natural bonded (bank sand) and synthetic(lake sand), which is generally preferred due to its more consistent composition.

Machining

New Guinea in 1943. Mobile Machine Shop truck of the US Army with machinistsworking on automotive parts.

Conventional machining, one of the most important material removal methods, isa collection of material-working processes in which power-driven machine tools,such as lathes,milling machines,and drill presses,are used with a sharp cuttingtool to mechanically cut the material to achieve the desired geometry. Machining isa part of the manufacture of almost allmetalproducts, and it is common for othermaterials, such aswoodandplastic,to be machined. A person who specializes inmachining is called a machinist.A room, building, or company where machiningis done is called a machine shop. Much of modern day machining is controlled bycomputersusingcomputer numerical control(CNC) machining. Machining can bea business, a hobby, or both.

The precise meaning of the term "machining" has evolved over the past 1.5

centuries as technology has advanced. During the Machine Age, it referred to(what we today might call) the "traditional" machining processes, such asturning,boring, drilling, milling, broaching, sawing, shaping, planing, reaming, andtapping,or sometimes to grinding.Since the advent of new technologies such aselectrical discharge machining, electrochemical machining, electron beammachining,photochemical machining, and ultrasonic machining, the retronym"conventional machining" can be used to differentiate the classic technologies from
http://en.wikipedia.org/wiki/Machine_toolshttp://en.wikipedia.org/wiki/Machine_toolshttp://en.wikipedia.org/wiki/Lathe_(tool)http://en.wikipedia.org/wiki/Lathe_(tool)http://en.wikipedia.org/wiki/Milling_machinehttp://en.wikipedia.org/wiki/Milling_machinehttp://en.wikipedia.org/wiki/Drill_presshttp://en.wikipedia.org/wiki/Drill_presshttp://en.wikipedia.org/wiki/Metalhttp://en.wikipedia.org/wiki/Metalhttp://en.wikipedia.org/wiki/Metalhttp://en.wikipedia.org/wiki/Woodhttp://en.wikipedia.org/wiki/Woodhttp://en.wikipedia.org/wiki/Woodhttp://en.wikipedia.org/wiki/Plastichttp://en.wikipedia.org/wiki/Plastichttp://en.wikipedia.org/wiki/Machinisthttp://en.wikipedia.org/wiki/Machinisthttp://en.wikipedia.org/wiki/Computerhttp://en.wikipedia.org/wiki/Computerhttp://en.wikipedia.org/wiki/Computer_numerical_controlhttp://en.wikipedia.org/wiki/Computer_numerical_controlhttp://en.wikipedia.org/wiki/Computer_numerical_controlhttp://en.wikipedia.org/wiki/Machine_Agehttp://en.wikipedia.org/wiki/Machine_Agehttp://en.wikipedia.org/wiki/Turninghttp://en.wikipedia.org/wiki/Turninghttp://en.wikipedia.org/wiki/Turninghttp://en.wikipedia.org/wiki/Boring_(manufacturing)http://en.wikipedia.org/wiki/Boring_(manufacturing)http://en.wikipedia.org/wiki/Drillinghttp://en.wikipedia.org/wiki/Drillinghttp://en.wikipedia.org/wiki/Milling_machinehttp://en.wikipedia.org/wiki/Milling_machinehttp://en.wikipedia.org/wiki/Broach_(metalwork)http://en.wikipedia.org/wiki/Broach_(metalwork)http://en.wikipedia.org/wiki/Sawinghttp://en.wikipedia.org/wiki/Sawinghttp://en.wikipedia.org/wiki/Shaperhttp://en.wikipedia.org/wiki/Shaperhttp://en.wikipedia.org/wiki/Planer_(metalworking)http://en.wikipedia.org/wiki/Planer_(metalworking)http://en.wikipedia.org/wiki/Reamerhttp://en.wikipedia.org/wiki/Reamerhttp://en.wikipedia.org/wiki/Tap_and_diehttp://en.wikipedia.org/wiki/Tap_and_diehttp://en.wikipedia.org/wiki/Grinding_machinehttp://en.wikipedia.org/wiki/Grinding_machinehttp://en.wikipedia.org/wiki/Electrical_discharge_machininghttp://en.wikipedia.org/wiki/Electrical_discharge_machininghttp://en.wikipedia.org/wiki/Electrochemical_machininghttp://en.wikipedia.org/wiki/Electrochemical_machininghttp://en.wikipedia.org/wiki/Electron_beam_machininghttp://en.wikipedia.org/wiki/Electron_beam_machininghttp://en.wikipedia.org/wiki/Electron_beam_machininghttp://en.wikipedia.org/wiki/Photochemical_machininghttp://en.wikipedia.org/wiki/Photochemical_machininghttp://en.wikipedia.org/wiki/Ultrasonic_machininghttp://en.wikipedia.org/wiki/Ultrasonic_machininghttp://en.wikipedia.org/wiki/Retronymhttp://en.wikipedia.org/wiki/Retronymhttp://en.wikipedia.org/wiki/File:Mobile_Machine_Shop_US_Army_1943.jpghttp://en.wikipedia.org/wiki/Retronymhttp://en.wikipedia.org/wiki/Ultrasonic_machininghttp://en.wikipedia.org/wiki/Photochemical_machininghttp://en.wikipedia.org/wiki/Electron_beam_machininghttp://en.wikipedia.org/wiki/Electron_beam_machininghttp://en.wikipedia.org/wiki/Electrochemical_machininghttp://en.wikipedia.org/wiki/Electrical_discharge_machininghttp://en.wikipedia.org/wiki/Grinding_machinehttp://en.wikipedia.org/wiki/Tap_and_diehttp://en.wikipedia.org/wiki/Reamerhttp://en.wikipedia.org/wiki/Planer_(metalworking)http://en.wikipedia.org/wiki/Shaperhttp://en.wikipedia.org/wiki/Sawinghttp://en.wikipedia.org/wiki/Broach_(metalwork)http://en.wikipedia.org/wiki/Milling_machinehttp://en.wikipedia.org/wiki/Drillinghttp://en.wikipedia.org/wiki/Boring_(manufacturing)http://en.wikipedia.org/wiki/Turninghttp://en.wikipedia.org/wiki/Machine_Agehttp://en.wikipedia.org/wiki/Computer_numerical_controlhttp://en.wikipedia.org/wiki/Computerhttp://en.wikipedia.org/wiki/Machinisthttp://en.wikipedia.org/wiki/Plastichttp://en.wikipedia.org/wiki/Woodhttp://en.wikipedia.org/wiki/Metalhttp://en.wikipedia.org/wiki/Drill_presshttp://en.wikipedia.org/wiki/Milling_machinehttp://en.wikipedia.org/wiki/Lathe_(tool)http://en.wikipedia.org/wiki/Machine_tools


15/21

the newer ones. The term "machining" without qualification usually impliesconventional machining.

Machining operations

processes are classified as turning, drilling and milling.Other operations falling

into miscellaneous categories include shaping, planing, boring,broaching andsawing.

Turning operations are operations that rotate the workpiece as the primarymethod of moving metal against the cutting tool. Lathes are the principalmachine tool used in turning.

Milling operations are operations in which the cutting tool rotates to bringcutting edges to bear against the workpiece. Milling machines are the

principal machine tool used in milling. Drilling operations are operations in which holes are produced or refined by

bringing a rotating cutter with cutting edges at the lower extremity intocontact with the workpiece. Drilling operations are done primarily in drill

pressesbut sometimes on lathes or mills. Miscellaneous operations are operations that strictly speaking may not be

machining operations in that they may not beswarfproducing operations butthese operations are performed at a typical machine tool. Burnishing is anexample of a miscellaneous operation. Burnishing produces no swarf but can

be performed at a lathe, mill, or drill press. Circle interpolating

The orbital drilling principle

Circle interpolating, also known as orbital drilling, is a process for creatingholes usingmachine cutters.

orbital drilling is based on rotating a cutting tool around its own axis andsimultaneously about a centre axis which is off-set from the axis of thecutting tool. The cutting tool can then be moved simultaneously in an axial
http://en.wikipedia.org/wiki/Turninghttp://en.wikipedia.org/wiki/Turninghttp://en.wikipedia.org/wiki/Drillinghttp://en.wikipedia.org/wiki/Drillinghttp://en.wikipedia.org/wiki/Milling_machinehttp://en.wikipedia.org/wiki/Milling_machinehttp://en.wikipedia.org/wiki/Boring_(manufacturing)http://en.wikipedia.org/wiki/Boring_(manufacturing)http://en.wikipedia.org/wiki/Broach_(metalwork)http://en.wikipedia.org/wiki/Broach_(metalwork)http://en.wikipedia.org/wiki/Sawhttp://en.wikipedia.org/wiki/Sawhttp://en.wikipedia.org/wiki/Drill_presshttp://en.wikipedia.org/wiki/Drill_presshttp://en.wikipedia.org/wiki/Drill_presshttp://en.wikipedia.org/wiki/Swarfhttp://en.wikipedia.org/wiki/Swarfhttp://en.wikipedia.org/wiki/Swarfhttp://en.wikipedia.org/wiki/Burnishing_(metalworking)http://en.wikipedia.org/wiki/Burnishing_(metalworking)http://en.wikipedia.org/w/index.php?title=Machine_cutter&action=edit&redlink=1http://en.wikipedia.org/w/index.php?title=Machine_cutter&action=edit&redlink=1http://en.wikipedia.org/w/index.php?title=Machine_cutter&action=edit&redlink=1http://en.wikipedia.org/wiki/Cutting_toolhttp://en.wikipedia.org/wiki/Cutting_toolhttp://en.wikipedia.org/wiki/File:Orbital-drilling.gifhttp://en.wikipedia.org/wiki/Cutting_toolhttp://en.wikipedia.org/w/index.php?title=Machine_cutter&action=edit&redlink=1http://en.wikipedia.org/wiki/Burnishing_(metalworking)http://en.wikipedia.org/wiki/Swarfhttp://en.wikipedia.org/wiki/Drill_presshttp://en.wikipedia.org/wiki/Drill_presshttp://en.wikipedia.org/wiki/Sawhttp://en.wikipedia.org/wiki/Broach_(metalwork)http://en.wikipedia.org/wiki/Boring_(manufacturing)http://en.wikipedia.org/wiki/Milling_machinehttp://en.wikipedia.org/wiki/Drillinghttp://en.wikipedia.org/wiki/Turning


16/21

direction to drill or machine a hole and/or combined with an arbitrarysidewards motion to machine an opening or cavity.

By adjusting the off-set, a cutting tool of a specific diameter can be used todrill holes of different diameters as illustrated. This implies that the cuttingtool inventory can be substantially reduced.

The term orbital drilling comes from that the cutting tool orbits around the

hole center. The mechanically forced, dynamic offset in orbital drilling hasseveral advantages compared to conventional drilling that drasticallyincreases the hole precision. The lower thrust force results in aburr-lessholewhen drilling in metals.When drilling in composite materials the problemwithdelaminationis eliminated.

Types of machining operation

There are many kinds of machining operations, each of which is capable ofgenerating a certain part geometry and surface texture.

Inturning,a cutting tool with a single cutting edge is used to remove material froma rotating workpiece to generate a cylindrical shape. The speed motion in turning is

provided by the rotating workpart, and the feed motion is achieved by the cuttingtool moving slowly in a direction parallel to the axis of rotation of the workpiece.

Drillingis used to create a round hole. It is accomplished by a rotating tool that istypically has two cutting edges. The tool is fed in a direction parallel to its axis ofrotation into the workpart to form the round hole.

Inboring,the tool is used to enlarge an already available hole. It is a fine finishingoperation used in the final stages of product manufacture.

In milling,a rotating tool with multiple cutting edges is moved slowly relative tothe material to generate a plane or straight surface. The direction of the feedmotion is perpendicular to the tool's axis of rotation. The speed motion is provided

by the rotating milling cutter. The two basic forms of milling are

Peripheral millingFace milling

Other conventional machining operations include shaping, planing, broaching andsawing. Also, grinding and similar abrasive operations are often included withinthe category of machining.

The cutting tool
http://en.wikipedia.org/wiki/Burrhttp://en.wikipedia.org/wiki/Burrhttp://en.wikipedia.org/wiki/Burrhttp://en.wikipedia.org/wiki/Metalhttp://en.wikipedia.org/wiki/Metalhttp://en.wikipedia.org/wiki/Composite_materialhttp://en.wikipedia.org/wiki/Composite_materialhttp://en.wikipedia.org/wiki/Delaminationhttp://en.wikipedia.org/wiki/Delaminationhttp://en.wikipedia.org/wiki/Delaminationhttp://en.wikipedia.org/wiki/Turninghttp://en.wikipedia.org/wiki/Turninghttp://en.wikipedia.org/wiki/Turninghttp://en.wikipedia.org/wiki/Drillinghttp://en.wikipedia.org/wiki/Drillinghttp://en.wikipedia.org/wiki/Boring_(manufacturing)http://en.wikipedia.org/wiki/Boring_(manufacturing)http://en.wikipedia.org/wiki/Boring_(manufacturing)http://en.wikipedia.org/wiki/Milling_machinehttp://en.wikipedia.org/wiki/Milling_machinehttp://en.wikipedia.org/wiki/Milling_machinehttp://en.wikipedia.org/wiki/Boring_(manufacturing)http://en.wikipedia.org/wiki/Drillinghttp://en.wikipedia.org/wiki/Turninghttp://en.wikipedia.org/wiki/Delaminationhttp://en.wikipedia.org/wiki/Composite_materialhttp://en.wikipedia.org/wiki/Metalhttp://en.wikipedia.org/wiki/Burr


17/21

A cutting tool has one or more sharp cutting edges and is made of a material that isharder than the work material. The cutting edge serves to separate chip from the

parent work material. Connected to the cutting edge are the two surfaces of the tool

The rake face; and

The flank.

The rake face which directs the flow of newly formed chip, is oriented at a certainangle is called the rake angle "". It is measured relative to the plane perpendicular

to the work surface. The rake angle can be positive or negative. The flank of thetool provides a clearance between the tool and the newly formed work surface,thus protecting the surface from abrasion, which would degrade the finish. Thisangle between the work surface and the flank surface is called the relief angle.There are two basic types of cutting tools

a. Single point tool; andb. Multiple-cutting-edge tool.

A single point tool has one cutting edge and is used for turning, boreing andplaning. During machining, the point of the tool penetrates below the original worksurface of the workpart. The point is sometimes rounded to a certain radius, calledthe nose radius.

Multiple-cutting-edge tools have more than one cutting edge and usually achievetheir motion relative to the workpart by rotating. Drilling andmillinguses rotating

multiple-cutting-edge tools. Although the shapes of these tools are different from asingle-point tool, many elements of tool geometry are similar.

Cutting conditions

Relative motion is required between the tool and work to perform a machiningoperation. The primary motion is accomplished at a certain cutting speed. Inaddition, the tool must be moved laterally across the work. This is a much slowermotion, called the feed. The remaining dimension of the cut is the penetration ofthe cutting tool below the original work surface, called the depth of cut.Collectively, speed, feed, and depth of cut are called the cutting conditions. Theyform the three dimensions of the machining process, and for certain operations,their product can be used to obtain the material removal rate for the process

where
http://en.wikipedia.org/wiki/Millinghttp://en.wikipedia.org/wiki/Millinghttp://en.wikipedia.org/wiki/Millinghttp://en.wikipedia.org/wiki/Cutting_speedhttp://en.wikipedia.org/wiki/Cutting_speedhttp://en.wikipedia.org/wiki/Cutting_speedhttp://en.wikipedia.org/wiki/Milling


18/21

the material removal rate in mm3/s, (in3/s), the cutting speed in m/s, (ft/min), the feed in mm, (in), the depth of cut in mm, (in).

Note: All units must be converted to the corresponding decimal (or USCU)units.

Machining operations usually divide into two categories, distinguished by purposeand cutting conditions:

Roughing cuts, andFinishing cuts.

WeldingWelding is a fabricationorsculpturalprocessthat joins materials, usually metalsor thermoplastics, by causing coalescence. This is often done by melting theworkpieces and adding a filler material to form a pool of molten material (the weldpool) that cools to become a strong joint, with pressure sometimes used inconjunction with heat,or by itself, to produce the weld. This is in contrast withsoldering and brazing, which involve melting a lower-melting-point material

between the workpieces to form a bond between them, without melting the

workpieces.

Gas metal arc welding

Many differentenergy sourcescan be used for welding, including a gasflame,anelectric arc, a laser, an electron beam, friction, and ultrasound. While often anindustrial process, welding can be done in many different environments, includingopen air,under waterand inouter space.Regardless of location, however, welding
http://en.wikipedia.org/wiki/United_States_customary_unitshttp://en.wikipedia.org/wiki/United_States_customary_unitshttp://en.wikipedia.org/wiki/Fabrication_(metal)http://en.wikipedia.org/wiki/Fabrication_(metal)http://en.wikipedia.org/wiki/Welded_sculpturehttp://en.wikipedia.org/wiki/Welded_sculpturehttp://en.wikipedia.org/wiki/Welded_sculpturehttp://en.wikipedia.org/wiki/Process_(science)http://en.wikipedia.org/wiki/Process_(science)http://en.wikipedia.org/wiki/Metalhttp://en.wikipedia.org/wiki/Metalhttp://en.wikipedia.org/wiki/Thermoplastichttp://en.wikipedia.org/wiki/Thermoplastichttp://en.wikipedia.org/wiki/Coalescence_(welding)http://en.wikipedia.org/wiki/Coalescence_(welding)http://en.wikipedia.org/wiki/Meltinghttp://en.wikipedia.org/wiki/Meltinghttp://en.wikipedia.org/wiki/Pressurehttp://en.wikipedia.org/wiki/Pressurehttp://en.wikipedia.org/wiki/Heathttp://en.wikipedia.org/wiki/Heathttp://en.wikipedia.org/wiki/Solderinghttp://en.wikipedia.org/wiki/Solderinghttp://en.wikipedia.org/wiki/Brazinghttp://en.wikipedia.org/wiki/Brazinghttp://en.wikipedia.org/wiki/Energy_sourcehttp://en.wikipedia.org/wiki/Energy_sourcehttp://en.wikipedia.org/wiki/Energy_sourcehttp://en.wikipedia.org/wiki/Firehttp://en.wikipedia.org/wiki/Firehttp://en.wikipedia.org/wiki/Firehttp://en.wikipedia.org/wiki/Electric_archttp://en.wikipedia.org/wiki/Electric_archttp://en.wikipedia.org/wiki/Laserhttp://en.wikipedia.org/wiki/Laserhttp://en.wikipedia.org/wiki/Electron_beam_weldinghttp://en.wikipedia.org/wiki/Electron_beam_weldinghttp://en.wikipedia.org/wiki/Friction_Weldinghttp://en.wikipedia.org/wiki/Friction_Weldinghttp://en.wikipedia.org/wiki/Ultrasoundhttp://en.wikipedia.org/wiki/Ultrasoundhttp://en.wikipedia.org/wiki/Underwater_weldinghttp://en.wikipedia.org/wiki/Underwater_weldinghttp://en.wikipedia.org/wiki/Underwater_weldinghttp://en.wikipedia.org/wiki/Outer_spacehttp://en.wikipedia.org/wiki/Outer_spacehttp://en.wikipedia.org/wiki/Outer_spacehttp://en.wikipedia.org/wiki/File:SMAW.welding.af.ncs.jpghttp://en.wikipedia.org/wiki/File:SMAW.welding.af.ncs.jpghttp://en.wikipedia.org/wiki/File:SMAW.welding.af.ncs.jpghttp://en.wikipedia.org/wiki/File:SMAW.welding.af.ncs.jpghttp://en.wikipedia.org/wiki/File:SMAW.welding.af.ncs.jpghttp://en.wikipedia.org/wiki/Outer_spacehttp://en.wikipedia.org/wiki/Underwater_weldinghttp://en.wikipedia.org/wiki/Ultrasoundhttp://en.wikipedia.org/wiki/Friction_Weldinghttp://en.wikipedia.org/wiki/Electron_beam_weldinghttp://en.wikipedia.org/wiki/Laserhttp://en.wikipedia.org/wiki/Electric_archttp://en.wikipedia.org/wiki/Firehttp://en.wikipedia.org/wiki/Energy_sourcehttp://en.wikipedia.org/wiki/Brazinghttp://en.wikipedia.org/wiki/Solderinghttp://en.wikipedia.org/wiki/Heathttp://en.wikipedia.org/wiki/Pressurehttp://en.wikipedia.org/wiki/Meltinghttp://en.wikipedia.org/wiki/Coalescence_(welding)http://en.wikipedia.org/wiki/Thermoplastichttp://en.wikipedia.org/wiki/Metalhttp://en.wikipedia.org/wiki/Process_(science)http://en.wikipedia.org/wiki/Welded_sculpturehttp://en.wikipedia.org/wiki/Fabrication_(metal)http://en.wikipedia.org/wiki/United_States_customary_units


19/21

remains dangerous, and precautions are taken to avoid burns, electric shock, eyedamage, poisonous fumes, and overexposure toultraviolet light.

Until the end of the 19th century, the only welding process was forge welding,which blacksmiths had used for centuries to join iron and steel by heating andhammering them.Arc weldingandoxyfuel weldingwere among the first processes

to develop late in the century, andresistance weldingfollowed soon after. Weldingtechnology advanced quickly during the early 20th century as World War I andWorld War II drove the demand for reliable and inexpensive joining methods.Following the wars, several modern welding techniques were developed, includingmanual methods like shielded metal arc welding, now one of the most popularwelding methods, as well as semi-automatic and automatic processes such as gasmetal arc welding,submerged arc welding,flux-cored arc weldingandelectroslagwelding.Developments continued with the invention of laser beam welding andelectron beam welding in the latter half of the century. Today, the sciencecontinues to advance.Robot weldingis becoming more commonplace in industrial

settings, and researchers continue to develop new welding methods and gaingreater understanding of weld quality and properties.

Shielded metal arc welding
http://en.wikipedia.org/wiki/Electric_shockhttp://en.wikipedia.org/wiki/Electric_shockhttp://en.wikipedia.org/wiki/Ultraviolet_lighthttp://en.wikipedia.org/wiki/Ultraviolet_lighthttp://en.wikipedia.org/wiki/Ultraviolet_lighthttp://en.wikipedia.org/wiki/Forge_weldinghttp://en.wikipedia.org/wiki/Forge_weldinghttp://en.wikipedia.org/wiki/Arc_weldinghttp://en.wikipedia.org/wiki/Arc_weldinghttp://en.wikipedia.org/wiki/Arc_weldinghttp://en.wikipedia.org/wiki/Oxy-fuel_welding_and_cuttinghttp://en.wikipedia.org/wiki/Oxy-fuel_welding_and_cuttinghttp://en.wikipedia.org/wiki/Oxy-fuel_welding_and_cuttinghttp://en.wikipedia.org/wiki/Resistance_weldinghttp://en.wikipedia.org/wiki/Resistance_weldinghttp://en.wikipedia.org/wiki/Resistance_weldinghttp://en.wikipedia.org/wiki/World_War_Ihttp://en.wikipedia.org/wiki/World_War_Ihttp://en.wikipedia.org/wiki/World_War_IIhttp://en.wikipedia.org/wiki/World_War_IIhttp://en.wikipedia.org/wiki/Shielded_metal_arc_weldinghttp://en.wikipedia.org/wiki/Shielded_metal_arc_weldinghttp://en.wikipedia.org/wiki/Gas_metal_arc_weldinghttp://en.wikipedia.org/wiki/Gas_metal_arc_weldinghttp://en.wikipedia.org/wiki/Gas_metal_arc_weldinghttp://en.wikipedia.org/wiki/Submerged_arc_weldinghttp://en.wikipedia.org/wiki/Submerged_arc_weldinghttp://en.wikipedia.org/wiki/Submerged_arc_weldinghttp://en.wikipedia.org/wiki/Flux-cored_arc_weldinghttp://en.wikipedia.org/wiki/Flux-cored_arc_weldinghttp://en.wikipedia.org/wiki/Flux-cored_arc_weldinghttp://en.wikipedia.org/wiki/Electroslag_weldinghttp://en.wikipedia.org/wiki/Electroslag_weldinghttp://en.wikipedia.org/wiki/Electroslag_weldinghttp://en.wikipedia.org/wiki/Electroslag_weldinghttp://en.wikipedia.org/wiki/Laser_beam_weldinghttp://en.wikipedia.org/wiki/Laser_beam_weldinghttp://en.wikipedia.org/wiki/Electron_beam_weldinghttp://en.wikipedia.org/wiki/Electron_beam_weldinghttp://en.wikipedia.org/wiki/Robot_weldinghttp://en.wikipedia.org/wiki/Robot_weldinghttp://en.wikipedia.org/wiki/Robot_weldinghttp://en.wikipedia.org/wiki/File:SMAW.welding.navy.ncs.jpghttp://en.wikipedia.org/wiki/Robot_weldinghttp://en.wikipedia.org/wiki/Electron_beam_weldinghttp://en.wikipedia.org/wiki/Laser_beam_weldinghttp://en.wikipedia.org/wiki/Electroslag_weldinghttp://en.wikipedia.org/wiki/Electroslag_weldinghttp://en.wikipedia.org/wiki/Flux-cored_arc_weldinghttp://en.wikipedia.org/wiki/Submerged_arc_weldinghttp://en.wikipedia.org/wiki/Gas_metal_arc_weldinghttp://en.wikipedia.org/wiki/Gas_metal_arc_weldinghttp://en.wikipedia.org/wiki/Shielded_metal_arc_weldinghttp://en.wikipedia.org/wiki/World_War_IIhttp://en.wikipedia.org/wiki/World_War_Ihttp://en.wikipedia.org/wiki/Resistance_weldinghttp://en.wikipedia.org/wiki/Oxy-fuel_welding_and_cuttinghttp://en.wikipedia.org/wiki/Arc_weldinghttp://en.wikipedia.org/wiki/Forge_weldinghttp://en.wikipedia.org/wiki/Ultraviolet_lighthttp://en.wikipedia.org/wiki/Electric_shock


20/21

Geometries that can be welded

Baisically,in this project wind energy is converted in to electrical and

mechanical energy.we used here a motor from which energy can be usedbut if we connect here a low power generator we can get electrical energy

as well.

This is our hand made project. Actually, this is the rough sketch of windmill

pump. From which many tasks can be taken. e.g Pumping of water

production of electricity etc etc.
http://en.wikipedia.org/wiki/File:Common_Joint_Types_ZP.svghttp://en.wikipedia.org/wiki/File:Common_Joint_Types_ZP.svg


21/21

, Recommendations

Since load shedding is a local problem in South Asia,more specifically inPakistan,we should immitate the measures taken by our neighbour country India tomake use of wind energy as much as possible.India is at no.5 in the list of those

countries which are amongst producing maximum energy from wind.

There is a fair number of sites in Pakistan where the windmill serups can beinstalled.At some places in Balochistan ,they are already in function.But there usein Pakistan is mostly for water pumping.If we install more and more windmills atsites near beaches, hills and valleys ,we can get the best of it.Suitable places forsuch setups may be Gawadar,Pasni,Panjgur,Gaddani,Thattha etc. where windskeep blowing round the year.

These mills can also be used for there secondary purpose i.e pumping the water inareas like Cholistan,Tharr,Kharan where fairly strong winds blow (although thetemperature of winds that blow there is faily high for human beings).General needsof water for human and cattle may be satisfied in this way.

Govt may impose a little amount of tax on the citizens of thar province to collectreveenue for the installation of setups,for a short duration of period (say 6 months).

Documents

Project Report 31