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I. INTRODUCTION
In our present electricity generation system we waste more than half of its resources.Especiallythetransmissionanddistributionlossesarethemainconcernofthepresentpowertechnology.Muchofthispoweriswastedduringtransmissionfrompowerplantgeneratorstotheconsumer.
Theresistanceofthewireusedintheelectricalgriddistributionsystemcausesalossof26-30%oftheenergygenerated.Thislossimpliesthatourpresentsystemofelectricaldistributionisonly70-74%efficient.Wehavetothinkofalternatestate-of-arttechnologytotransmitanddistributetheelectricity.Now-a-daysglobalscenariohaschangedalotandtherearetremendousdevelopmentineveryfield.Ifwedon‟tkeeppacewith the developmentofnewpower technologywehavetoface adecreasingtrendinthedevelopment of powersector.Thetransmissionofpowerwithoutwiresmaybeonenoblealternativeforelectricitytransmission.
Projectionsoffutureenergyneedsoverthisnewcenturyshowanincreasebyafactorofatleasttwoandhalf,perhapsbyasmuchasa factoroffive. Allofthe scenarios indicatecontinuinguseoffossilsources, nuclear,andlargehydro.However,thegreatestincreasescomefrom“newrenewable”andallscenariosshowextensiveuseofthesesourcesby2050.Indeed,theprojectionsindicatethattheamountofenergyderivedfromnewrenewableby2050willexceedthatpresentlyprovidedbyoilandgascombined.Thiswouldimplyamajorchangeintheworld‟senergyinfrastructure.Itwouldbeaherculeantasktoacquirethisprojectedamountofenergy[1].
Wirelesstransmissionofpower,alsocalledwirelesspowertransfer(WPT),isameansofdeliveringpowertoanend-usedevicewithoutwiresorcontacts.Oneoftheoldestknownpowertransmissiontechnologies,WPTisseeingaresurgenceofinterest.Scientistsandengineershaveknownoverthepastcenturythattransferringelectricpowerdoesnotrequirewirestobeinphysicalcontact.Wirestypicallyalloweddevicestoreceivebothpowerandcommunicatewithotherdevices.Aswirelessdatatransmissioneliminatestheneedforwirestocarrydata,thereisagrowingneedtofind waystoprovidepowerwithoutwiresmakingdevicestrulyportableandmobile.Withtheexplosivegrowthinwirelessdataapplications,themarketpotentialforwirelessenergytransfertechnologieshasseenadramaticincrease[2].
TheSolarPowerSatelliteenergysystemistoplacegiantsatellites,coveredwithvastarraysofsolarcells,ingeosynchronousorbit22,300milesabovetheEarth'sequator.Eachsatellitewillbeilluminatedbysunlight24hoursadayformostofthe year.Becauseofthe23"tiltoftheaxis,thesatellitespasseitheraboveorbelowthe
Earth‟sshadow.Itisonlyduringtheequinoxperiodinthespringandfallthattheywillpassthroughtheshadow.Theywillbeshadowedforlessthan1%ofthetimeduringtheyear.Thesolarcellswillconvertsunlighttoelectricity,whichwillthenbechangedtoradio-frequencyenergybyatransmittingantennaonthesatelliteandbeamedtoareceiversiteonEarth.
Itwillbereconvertedtoelectricitybythereceivingantenna,andthepowerwouldthenberoutedintoournormalelectricdistributionnetworkforusehereontheEarth.Asearliermentioned,oneof themajorissueinpowersystemisthelossesthatoccursduringthetransmissionanddistributionofelectricalpower.Asthedemandincreasesdaybyday,thepowergenerationincreasesandthepowerlossisalsoincreased.Theefficiencyofpowertransmissioncanbeimprovedtocertainlevelbyusinghighstrengthcompositeoverheadconductorsandundergroundcablesthatusehightemperaturesuperconductor.But,thetransmissionisstillinefficient.
Accordingto the World Resources Institute (WRI), India‟selectricitygridhas thehighesttransmissionanddistributionlossesintheworld–awhopping27%.NumberspublishedbyvariousIndiangovernmentagenciesputthatnumberat30%,40%andgreaterthan40%.Thisisattributedtotechnicallosses(grid‟sinefficiencies)andtheft.Anyproblemcanbesolvedbystate–of-the-arttechnology.TheabovediscussedproblemcanbesolvedbychoosinganalternativeoptionforpowertransmissionwhichcouldprovidemuchhigherEfficiency,lowtransmissioncostandavoidpowertheft.MicrowavePowerTransmissionisoneofthepromisingTechnologiesandmaybetherighteousalternativeforefficientpowertransmission[3].