Page - 193 - in Short-Term Load Forecasting by Artificial Intelligent Technologies

Energies2018,11, 1948 andanLithiumiron(Li-Fe)battery. Theyshowedthat the integrationof thePEMFCimprovedsystem reliability, and that tuning thePVandbatteryunits greatly reduced the systemcost. Thepresent paper extends these ideas and discusses the impacts of WTs and a hydrogen electrolyzer on systemperformance. AWT convertswind power into electricity. Many factors, such aswind speed, air density, therotorsweptarea,andthepowercoefficientof themotor,affect theamountofpowerextractedfrom WTs. Forexample,Bonfiglioetal. [5]modeledWTsequippedwithdirect-drivepermanentmagnet synchronousgenerators. Theyusedthemodel toexaminethe influencesofactivepower lossonthe effectiveness ofwindgenerator control and appliedDigsilent Power Factory to verify the results. Pedraetal. [6]builtfixed-speed inductiongeneratormodelsusingPSpiceandPSCAD-EMTDCcodes Theycomparedsingle-cageanddouble-cagemodels, andshowedthat the latterwasmoresuitable forfixed-speedWTsimulation. Leeetal. [7]assessed large-scaleapplicationofsolarandwindpower in 143urban areas. Theproposed systemwas shown to lead to a balance of the building energy consumption.Maouedjaetal. [8] constructedasmallhybridsysteminAdrar,Algeria, andconcluded thatwindenergycancomplimentsolarenergy.AlGhaithietal. [9]analyzedahybridenergysystemin MasirahIslandinOman.Thesimulationresults showedthatahybridsystemcomposedofPV,aWT, andanexistingdieselpowersystemis themosteconomicallyviable,andcansignificantly improve voltageprofiles.DevrimandBilir[2]alsofoundthatahybridsystemwithaWTcanperformbetterthan onewithoutaWTinAnkara,Turkey.However,ChenandWang[10] reachedtheoppositeconclusion in their analysis of a green building inMiao-Li county of Taiwan equippedwith a hybridpower systemconsistingofPVarrays,aWT,aPEMFC,ahydrogenelectrolyzer, andbatterysets. Theyfound thatwindandsolarenergyhadsimilarprofiles,andconcludedthataWTwasunsuitablebecause it increasedthecostof thesystembutdidnotsignificantlycompensate therenewableenergyof thePV array. Therefore, the inclusionofWTs inahybridsystemshoulddependonlocalweatherconditions. Hydrogenelectrolyzation isanewmethodofenergystorage,whereredundantenergyisused toproducehydrogen that can thenbeutilizedbyPEMFCs toproduce electricitywhen thepower supply is insufficient. Forexample,Chennoufetal. [11]utilizedsolarenergy toproducehydrogen inAlgeria. Theydemonstratedthathydrogenconversionefficiencywasbestunder lowvoltageand hightemperatureconditions. Tribioli etal. [12]analyzedanoff-gridhybridpowersystemwithtwo energystoragemethods: a lead-acidbatteryandreversibleoperationofaPEMFC.Theycombinedthe systemwithadieselengineandshowedthat theconsumptionof fossil fuels canbegreatly reducedby integratingasuitablerenewablepowerplanttomatchtheloads.Cozzolinoetal. [13]appliedthemodel toanalyzeaparticular case: theTUNeIT (Tunisiaand Italy)Project. The simulationdemonstrated analmostself-sustainingrenewablepowerplant thatconsistedof1MWWT,1.1MWPV,a72kWh battery,a300kWfuelcell,a300kWdieselenginetocopewithpowerdemandatacostof0.522€/kWh. Aouali et al. [14] built a PVarray andhydrogen electrolyzermodel based ondynamic equations. Theyconductedsmall-scaleexperimentsandshowedthat theexperimental responsesfitted themodel responses. Rahimiet al. [15] analyzed theeconomicbenefitsofutilizingwindenergy inhydrogen electrolysis inManjil andBinaloud, Iran. They showed that a stand-alone applicationwasmore expensive thananon-gridonebecause the formerrequired largerWTs. Bianchietal. [16]analyzed ahybridsystemthatutilizedtwostoragemethods: asolarbatterysystemandasolarbattery–hydrogen electrolyzer fuelcell system.Theyfoundthat theconversionefficiencyofstoredenergywasabout90% with theuseofbattery,andabout20%with theelectrolyzerandPEMFC.Bocklischetal. [17]proposed amultistoragehybridsystemthatcombinedshort-termstoragebybatteriesandlong-termstorageby hydrogen. TheyconvertedexcessivePVenergyinsummerintohydrogenandhydrogenintoelectricity andheat inwinter. Thepower exchangedwith thepublic gridwas smaller andmorepredictable comparedwith thatofaconventionalPVbattery–hybridsystem.Asweatherconditionshaveamajor influenceontheperformanceofhybridpowersystems, climatedatamustbe incorporated into the designofanyhybridsystem. For instance, Ikhsanetal. [18] collectedweatherdata toestimate the energyflowintohybridsystemsandtoresize thesystemcomponents. Their resultsdemonstrated 193