Retrofits for Energy Efficient Office Buildings

22 Pages·2017·8.24 MB·English

sustainability
Article
Retrofits for Energy Efficient Office Buildings:
Integration of Optimized Photovoltaics in the Form of
Responsive Shading Devices
HardiK.Abdullah1,2,* ID andHalilZ.Alibaba1,* ID
1 DepartmentofArchitecture,FacultyofArchitecture,EasternMediterraneanUniversity,Famagusta99628,
NorthCyprus,viaMersin10,Turkey
2 DepartmentofArchitecture,CollegeofEngineering,SalahaddinUniversity-Erbil,Erbil44002,
Kurdistan,Iraq
* Correspondence:[email protected](H.K.A.);[email protected](H.Z.A.);
Tel.:[phone](H.K.A.);[phone](H.Z.A.)
Received:11August2017;Accepted:9November2017;Published:15November2017
Abstract: Thisstudypresentsaretrofitstrategy: integratingoptimizedphotovoltaics(PV)intheform
ofresponsiveshadingdevicesusingadual-axissolartrackingsystem. Aprototype-basedmodel
wasfabricatedtocomparetheefficiencyofPVinthisimplementationwiththeconventionalfixed
installation. Theofficebuilding,T1EmpireWorldinErbil,wasselectedasaretrofitcasestudyandfor
theapplicationoftheproposedintegrationsystem.Inordertoassesstheeffectivenessoftheproposed
retrofitmethod,theenergyperformanceofthebasecaseissimulatedtobecomparedlaterwiththe
energyperformancesimulationsaftertheintegrationtechnique. Theamountofgeneratedelectricity
fromthePVsurfacesoftheintegratedshadingelementsiscalculated. Theenergysimulationswere
performedusingOpenStudio®(NREL,Washington,DC,USA),EnergyPlusTM(NREL,Washington,
DC,USA),andGrasshopper/Ladybugtoolsinwhichtheessentialresultswererecordedforthe
baselinereference,aswellastheenergyperformanceoftheretrofittedbuilding.Theresultsemphasize
thatthePV-integratedresponsiveshadingdevicescanmaximizetheefficiencyofPVcellsby36.8%in
comparisontothefixedinstallation. Theintegratedsystemcanprovideapproximately15.39%ofthe
electricitydemandforoperatingthebuilding. Thisretrofitmethodhasreducedthetotalsiteenergy
consumptionby33.2%comparedtotheexistingbuildingperformance. Totalelectricityend-useof
thevariousutilitieswasloweredby33.5%,andthetotalnaturalgasend-useofheatingdemandwas
reducedby30.9%. Therefore, thepercentagereductioninelectricitycoolingdemandinJulyand
Augustis42.7%duetominimizingtheheatgaininsummerthroughblockingthesun’sharshrays
frompenetratingintointeriorspacesofthebuilding. Ingeneral,thissystemhasmultiplebenefits,
startingwithbeingextremelyefficientandviableingeneratingsustainablealternativeenergy—which
istheglobalgrowingconcernoftoday’ssustainabledevelopment—providingthermalcomfortfor
occupants,andgrantingadynamicappearancetothebuildingwhenthePV-integratedelements
rotateaccordingtothesun’spositioninthesky.
Keywords:buildingretrofit;photovoltaicoptimization;responsiveshadingdevices;energyefficiency;
officebuilding
1. Introduction
Sustainability concerns and technological evolution are intent in creating energy-efficient
buildingsandgeneratingelectricityfromsolarenergythroughemergentphotovoltaic(PV)-integrated
techniques. Due to the large glazed façades and the nature of office activities [1], office buildings
consumeagreateramountofenergythanothertypesofcommercialbuildings[2].Theglazedenvelopes
Sustainability2017,9,2096;doi:10.3390/su9112096 www.mdpi.com/journal/sustainability
Sustainability2017,9,2096 2of22
ofexistingofficebuildingsresultinglare,heatgainsinsummer,heatlossesinwinter,andincreasing
coolingandheatingloads,specificallyinhotandaridclimates[3].
Externalshadingdevicesareprofitablyusedtoovercometheshortfallsofglazedfaçadesand
enhancebuildingperformance.Asaretrofitstrategy,multiplerequirementsofbuildingsandoccupants
areachievedthroughtheintegrationofshadingdeviceswithPV,suchaspromotingdaylight,reducing
glare,minimizingheatgainandcoolingloadsinsummer,andgeneratingelectricityfromPVcells.
However,thisimplementationhasnotyetbeenfullyoptimizedandthechallengetocapturemore
solarradiationremains. Thereisaneedtoassessthisintegrationonawholemodelofficebuildingto
examinethepotentialofthistechniqueinreducingenergyend-usesandproducingelectricityfrom
PVcells.
Themainaimofthisstudyistoproposeanenergy-efficientretrofitstrategythatprofitablysuits
officebuildings. ThisresearchattemptstomaximizetheefficiencyofPVinaparticularlocation(Erbil),
andthenintegrateoptimizedPVintheformofexteriorresponsiveshadingdevices. Thepotential
benefitsincludemaximizingtheefficiencyofPVcells,optimizingtheeffectivenessofshadingdevices,
promotingsustainabilitybyreducingmaterialsand,whenproducingelectricityfromtherenewable
solarenergy, decreasingcoolingloadssimultaneouslybyreducingheatgainviasolarradiationin
summer. By lowering total energy consumption and carbon dioxide emissions, this may result in
acleanenvironmentandlesscostlyutilitybills.
1.1. RetrofitsforanEnergy-EfficientOfficeBuilding
Retrofit involves modification to existing buildings, particularly commercial buildings,
which improves energy efficiency and decreases energy demand through the addition of new
technology. Theapplicationofretrofitisultimatelyaffectedbyconsciousnessandthebehaviorof
occupantsconcerningenergysavingstrategies. MentionedbytheEnergyEfficiencyandConversation
CleaningHouse(EECCHI)[4],variousretrofitapproacheshavebeenimplementedondifferentlevels,
suchasarchitecture,structure,electricalandmechanical,interiordesign,andsoforth.Whenretrofitting
anofficebuilding,architecturalaspectsaresubstantiallyconsideredinmodifications,predominantly
thefaçade[5],asitisusedfordiversetechnicalinstallations[6].
Retrofits through the implementation of photovoltaics have grown rapidly in the digital
innovationageduetotheurgentdemandofproducingelectricityfromrenewableenergysources[7].
However,utilizingtheintegrationofPVsolar-trackingtechnologyintheformofresponsiveshading
devicesisrecent,anditisnotobservedwidelythroughtheexperimentsofretrofitting. Inthepast,
the majority of the photovoltaic implementations have generated low power due to using fixed
installations;thus,photovoltaiccellscannotachieveoptimalefficiency.
AccordingtotheU.S.EnergyInformationAdministration(EIA),officebuildingsconsumemore
energy than any other commercial building type, in which the energy use of offices is recorded
as 17% [2]. Therefore, the application of retrofits can be profitably integrated into office buildings.
Thebuildingfaçadeisthemainconcernforarchitectstotargetintheretrofittingprocessduetothe
feasibilityandcapabilityofthefaçadeinenhancingbothaestheticaspectsandenergyperformanceof
buildings. Differentformsofembeddingfaçade-PVhavebeenutilized,suchasapplyingPVpanelsas
cladding,theintegrationofPVpanelsintofaçadewindows,andusingPVasshadingdevices[8].
1.2. IntegrationofPhotovoltaicsasResponsiveShadingDevices
Solar shading devices play a vital role in boosting the interior environment, providing better
comfortforoccupantsandloweringheatgaininsummer,whichresultsinadecreasingcoolingload
andminimizingenergyconsumption[8].Accordingtopreviousresearch[9],thesignificantadvantages
ofshadingdevicesare:
• Thermalcomfort(coolingloadsandartificiallightdemandreduction);
• Visualcomfort(reducingglareandproductivityimprovement);
Sustainability2017,9,2096 3of22
• Daylightcontrolling(maintainadequatedaylightlevel);
• Users’interactionandmorespaceuse(improvingtheenvironment);and
• ESunstvaiinraobnilimty 2e0n17t,a 9l, p20r9i6v acy(protectinginternalspacesfromtheexternalenvironment). 3 of 21
T• heaUpsperlsi’c ainttieornacotifoenx atenrdi omrosrhea sdpiancge udseev (iicmepsrionvtienggr athtee denwviirtohnPmVenht)a;s arnadp idlyemergedinthepast
• Environmental privacy (protecting internal spaces from the external environment).
decade. Thistechniqueperformsmultipletaskssimultaneously,fromcontrollingdaylighttoproviding
thermalaTnhde vaipspulaiclactoiomn foofr etxatenrdiogr esnhaedraintign dgesvoicleasr ienlteecgtrraicteidty .wSitthu dPVie shaesn rcaopuidralyg eemeleercgterdic iinty thper opdasut ction
throudgehcasdhea.d Tinhgisd teevcihcneisqiunet epgerraftoerdmws imthuPltVipl[e8 ,1ta0s–k1s7 ]s.imInupltraenveioouusslye, xfpreormim ceonnttsr,ofillxinegd sdhaaydliginhgt dtoe vices
integrpartoevdidwinigth thPeVrmwael raenads sveissuseadl c[o1m0,f1o1r]t, aanndd gtehneeorapteinragt sioonlaro felceocntrtircoitlyli.n Sgtutdhieesti letnrcootuartaiogne belyecatrciocimtyp uter
production through shading devices integrated with PV [8,10–17]. In previous experiments, fixed
basedonmeasuredenvironmentalconditionswasevaluatedandoptimized[12,13]. Thesestudies
shading devices integrated with PV were assessed [10,11], and the operation of controlling the tilt
reportthatPV-integratedshadingdevicesgenerateaconsiderableamountofelectricityandreduce
rotation by a computer based on measured environmental conditions was evaluated and optimized
coolingloadthroughnovelcontrolofdaylight,therebyloweringenergyconsumption.
[12,13]. These studies report that PV-integrated shading devices generate a considerable amount of
Basedontheaboveassumptions,PV-integratedshadingdevicescanbefurtheroptimizedwhen
electricity and reduce cooling load through novel control of daylight, thereby lowering energy
usingcoansduumapl-taioxni.s tracking system to maximize the efficiency of PV in producing electricity and
optimizinBgassehda donin tghee affbeocvtse oasnsuthmeprtmioanls,c PoVm-finotretg.rated shading devices can be further optimized when
using a dual-axis tracking system to maximize the efficiency of PV in producing electricity and
1.3. Pohpottiomviozlitnagic sahnaddiEnfgfi ceifefencctys oOnp tthimerimzaatli ocnomfort.
In order to maximize the use of renewable energy through retrofitting façades, utilizing
1.3. Photovoltaic and Efficiency Optimization
photovoltaic panels is an efficient method to produce electricity from solar energy [14]. A semi-
In order to maximize the use of renewable energy through retrofitting façades, utilizing
transparent photovoltaic panel has been widely used in re-skinning façades of various types of
photovoltaic panels is an efficient method to produce electricity from solar energy [14]. A
buildings, for instance, the Mataro Public Library in Spain and the De Kleine Aarde Boxtel in the
semi-transparent photovoltaic panel has been widely used in re-skinning façades of various types of
Netherlands. Thiskindofphotovoltaicpanelisusedasare-skinningsolutionforanofficebuildingin
buildings, for instance, the Mataro Public Library in Spain and the De Kleine Aarde Boxtel in the
Shanghai. TheproblemwasthatthebuildinghadaglazedfaçadeandtheclimateofShanghaicity
Netherlands. This kind of photovoltaic panel is used as a re-skinning solution for an office building
ishotinsummerandcoldinwinter;therefore,thefacadewasre-skinnedutilizingsemi-transparent
in Shanghai. The problem was that the building had a glazed façade and the climate of Shanghai city
photoisv hooltta iinc spuamnmelesrt oanrde dcoulcde inth weihneteart; gthaeirnefaonrde, pthreo dfaucacdeee wleacstr riec-istyk.inTnheuds u,ttihliezyinfgo suenmdi-tthraantstphairsesnyt stem
canpprhoodtuovceol7ta%ic opfatnheelsb tuoi lrdeidnugc’es tehnee rhgeyat cgoanisnu amndp tpiornodpuecre yeeleacrtr[i1c5it]y.. TThheuss,a mtheeys ofoluutnido nthuaste tdhiosn the
campsuysstoefmt hceanN porrowduegceia 7n%U onf itvheer bsiutiyldoinfgS’csi eennceergayn cdonTseucmhnpotiloong ype(rN yTeNarU [1)5i]n. TThroe nsdamheei msoltuoticoonv uesregdl azed
façadoens tahned cmamapxuims oizf eththe eNuosrewoegfiraenn Uewniavbelresietyn eorfg Syci[e1n6c]e. aHnodw Teevchenr,oilnogbyo t(hNTaNboUv)e inca Tsreosn,dthheeyimf atiol edto
cover glazed façades and maximize the use of renewable energy [16]. However, in both above cases,
raisetheenergyefficiencyofphotovoltaicpanelsbecausefixedsysteminstallationswereused. Simply
they failed to raise the energy efficiency of photovoltaic panels because fixed system installations
placingalargenumberofPVpanelsonabuildingmayonlykeepthePVcellsperpendiculartothe
were used. Simply placing a large number of PV panels on a building may only keep the PV cells
sun’sraysfor10–15%oftheday’ssunlighthours. Figure1showshowtheefficiencydecreaseswhen
perpendicular to the sun’s rays for 10–15% of the day’s sunlight hours. Figure 1 shows how the
theangleofsun’srayshittingthePVcellfallsawayfrom90◦.
efficiency decreases when the angle of sun’s rays hitting the PV cell falls away from 90°.

Figure 1. The relation between photovoltaic (PV) cell efficiency and angle of the sun’s rays [2].
Figure1.Therelationbetweenphotovoltaic(PV)cellefficiencyandangleofthesun’srays[2].
Considering that sufficient amounts of the solar radiation reach our planet, Taylor [17] states
Cthoant s“iIdt ehrains gbethena tcsaulcfufilcaiteendt tahmato tuhne tssoolafrt hraedsioatliaornr afadlliiantgio onnr ethaec heaoruthr’ps laatnmeot,spThayerleo re[v1e7ry] shtaotuers that
“Ithacsoublede, nifc afulclluyl aetxepdlotihteadt, tmheeesto tlhaer raandniuaatli oennefraglyli nngeeodns tohf etheea rwtho’rslda”t.m Toos pachheireevee vtherisy ghooaul ranc ould,
iffulliynteexllpigleonitte dso,lmar etertacthkienagn snyusatelmen iesr gnyeendeeedd ssoo fthtahte pwhootroldv”o.ltTaioc accehllise vcaent hciosngvoeartl athnei nmtealxliimgeunmt solar
amount of solar energy to electricity. An intelligent solar tracker has been invented and proposed;
trackingsystemisneededsothatphotovoltaiccellscanconvertthemaximumamountofsolarenergy
however, it has not been implemented as a retrofit strategy of re-skinning façades yet, and all
toelectricity. Anintelligentsolartrackerhasbeeninventedandproposed;however,ithasnotbeen
previous experiments of solar tracking systems were installed for testing purpose or individual use.
implementedasaretrofitstrategyofre-skinningfaçadesyet,andallpreviousexperimentsofsolar
For instance, a single prototype dual-axis solar tracker was used in a pilot project that is located in
trackingsystemswereinstalledfortestingpurposeorindividualuse. Forinstance,asingleprototype
Sarawak, Malaysia, to produce more electricity from photovoltaic cells [7].
Sustainability2017,9,2096 4of22
dual-axissolartrackerwasusedinapilotprojectthatislocatedinSarawak,Malaysia,toproduce
moreelectricityfromphotovoltaiccells[7].
FSursotaminabtihlitey 2a0b17o, v9,e 20l9it6e raturereview,itcanbemerelyobservedthatthereisanobviousg4 aofp 21i nthe
systemofphotovoltaicimplementation: thatis,usingafixedmethod. Thissystemrequireslesscost
From the above literature review, it can be merely observed that there is an obvious gap in the
andlowenergyproductioncomparedtoadual-axissolartracker. Asthedemandformaximizing
system of photovoltaic implementation: that is, using a fixed method. This system requires less cost
theuseofrenewableenergy,morespecificallysolarenergy,increases,theneedtoutilizedual-axis
and low energy production compared to a dual-axis solar tracker. As the demand for maximizing
trackingsystemsforphotovoltaicpanelswillincrease. Hence,answersforseriousquestionswillbe
the use of renewable energy, more specifically solar energy, increases, the need to utilize dual-axis
needed,suchashowmuchextraenergycanbeproducedviausingsuchtrackingtechnologyinstead
tracking systems for photovoltaic panels will increase. Hence, answers for serious questions will be
ofafinxeeeddeidm, spulcehm aesn htoawti omnu.cHh oexwtrma euncehrgeyx ctarna beeffi pcrioednuccyedc avniat uhseinpgh soutcohv torlatcakiicnpg atencehlnsoalocqgyu iirnestbeaydu sing
thistoefc ha nfioxleodg iym?plementation. How much extra efficiency can the photovoltaic panels acquire by using
this technology?
2. MaterialsandMethods
2. Materials and Methods
Toaddresstheresearchobjectives,thisstudyemploysanempiricalmethodologythroughdifferent
approachTeos .aFdidrsrtelsys, ttohem raesxeiamrcihz eotbhjeecetifvfiecsi, etnhcisy sotfudpyh oetmovpololytas icasn, aempproirtiocatyl pmee-tbhaosdeodloegxyp ethrriomuegnht was
different approaches. Firstly, to maximize the efficiency of photovoltaics, a prototype-based
implementedaimingatcollectingreal-timedata. Then,anofficebuildinginErbilwasselectedasacase
experiment was implemented aiming at collecting real-time data. Then, an office building in Erbil
studytoapplytheproposedintegrationsystemandevaluatetheenergyperformanceofthebuilding
was selected as a case study to apply the proposed integration system and evaluate the energy
beforeandafterthesystemintegration. Finally,computermodellingandsimulationswereperformed
performance of the building before and after the system integration. Finally, computer modelling
toinvestigatetheenergyperformanceofthebasecasebuildingandthesituationaftertheintegration
and simulations were performed to investigate the energy performance of the base case building and
ofphotovoltaicintegratedresponsiveshadingdevices. Therefore,theamountofgeneratedelectricity
the situation after the integration of photovoltaic integrated responsive shading devices. Therefore,
throuthgeh atmhiosuanpt opfl igceanteiorant,eda selwecetrlilcaitsy tthhreoruegdhu tchtiiso anppalmicaotuionnt, ians wtheell eans ethrge yreddeumctiaonnd a,mwoeurnet icna ltchue lated
andreenceorrgdye dde.mand, were calculated and recorded.
2.1. A2.P1.r Aot oPtryoptoet-yBpaes-BedasEedx pEexrpiemriemnetnt
AphAy spichaylspicraolt optryoptoetyopfet hoef PthVe- inPtVe-ginratetgedratreedsp roenspsiovnesisvhea sdhinadgindge vdiecveiwcea wsmasa mdeadtoe tteos ttethste tahme ount
amount of efficiency optimization compared to the conventional (fixed) installation system. This
ofefficiencyoptimizationcomparedtotheconventional(fixed)installationsystem. Thisautomated
automated system is characterized by a dual-axis solar tracking ability, by moving the two rotating
system is characterized by a dual-axis solar tracking ability, by moving the two rotating axes
axes simultaneously, which leads the PV panel to track the sun. Hence, the shading element
simultaneously,whichleadsthePVpaneltotrackthesun. Hence,theshadingelementautomatically
automatically rotates to stay at 90° to the sun’s rays for maintaining maximum efficiency of the PV in
rotatestostayat90◦ tothesun’sraysformaintainingmaximumefficiencyofthePVinFigure2.
Figure 2.

Figure 2. PV-integrated responsive shading device with the dual-axis solar tracking system [18].
Figure2.PV-integratedresponsiveshadingdevicewiththedual-axissolartrackingsystem[18].
The research experiment needed a digital model to validate the physical model that was
Tdehseigrneesdea rinch Gexrapsesrhiompepnert n3eDe d(eRdobaedrti gMitaclNmeeold &el tAosvsaolciidataetse, tWheapshhiynsgitcoanl, mDoCd,e lUtShAat) w[1a8s] d(easni gned
inGraalgssohriothpmpiecr a3nDd g(RenoebreartitvMe mcNodeeelllin&g Aplsusgoicni afoter sR,hWinaos h3Din [g1t9o] na,pDplCic,atUioSnA s)of[t1w8a]r(ea),n wahlgicohr aitlhlomwisc and
generthaeti dviegimtalo mdoedlleinl tgo pbelu cgoninnefcoterdR toh itnheo p3hDysi[c1a9l ]praoptoptlyipcaet tihornousgohf taw sapreec)ia,l wschriipcthinga lGlorwassshtohpepedri gital
mode3lD tpolubge-inc oanndn eacnt eodpetno-sothurecep ehleycstircoanlicps rpolatotftoyrpme. Tthhero purgothotyapsep ceocnisaisltss corfi pa t1i2n5g mGmr a×s 1s2h5o pmpme r 3D
monocrystalline silicon (also called single-crystalline silicon) PV cell, two micro servos 9 g each, 4 ×
plug-in and an open-source electronics platform. The prototype consists of a 125 mm × 125 mm
10,000 LDR (light-dependent resistor) sensors, 4 × 10,000 Ω resistors, jumper wires, breadboard, DC
monocrystalline silicon (also called single-crystalline silicon) PV cell, two micro servos 9 g each,
voltmeter/ammeter, and utility parts. A laser cutter was used to digitally fabricate the utility parts
4×10,000LDR(light-dependentresistor)sensors,4×10,000Ωresistors,jumperwires,breadboard,
and some soldering was applied to attach LDR sensors with the jumper wires. Two LDR sensors
DC voltmeter/ammeter, and utility parts. A laser cutter was used to digitally fabricate the utility
were positioned on the top and bottom of the shading element controlling tilt rotations, while the
other two LDR sensors were placed on the right and left to control azimuth rotations. This prototype
Sustainability2017,9,2096 5of22
partsandsomesolderingwasappliedtoattachLDRsensorswiththejumperwires. TwoLDRsensors
werepositionedonthetopandbottomoftheshadingelementcontrollingtiltrotations, whilethe

Sustainability 2017, 9, 2096 5 of 21
othertwoLDRsensorswereplacedontherightandlefttocontrolazimuthrotations. Thisprototype
ispiso pwoewreedredb ybya ala lpatpotpopv ivaiaU USSBBa anndda ann AArrdduuiinnoo UUnnoo [[2200]] ((aann ooppeenn-s-soouurcrec eeleelcetcrtornoincsic psrportoottyoptyinpgin g
plaptlfaotrfmor)m. I)n. Ino rodredretro tote tsetstt htheev viaiabbiilliittyy ooff tthhee pprroottoottyyppee,, tthhee AArrdduuininoo mmicircorcoocnotnrotrlolelrle arllaolwlosw rsearle-atilm-tiem e
dadtaatfla ofwlowb ebtwetweeenent htehed digigitiatall aanndd pphhyyssiiccaall mmooddeellss tthhrroouugghh FFiriereflflyy [2[12]1 ](a( aseste tofo fcocmomprpehreehnesinvsei ve
sofstowftawrearteo tooloslds eddeidciactaetdedt otob brrididggiinngg tthhee ggaapp bbeettwweeeenn GGrraasssshhooppppere r3D3D, t,hteh AerAdrudinuoin moimcrioccroonctornotllreorl,l er,
andanidn piunpt/uot/uotuptuptudt edveicveicse)ss)c rsicprtipstasn adn,dth, uths,urse, arle-tailm-tiemdea tdaactaa ncabne rbeea drefardo mfrothme LthDeR LsDeRns soernssionrFs iirne fly.
FirTefhlye. prototype was fabricated to collect real-time data and compare the efficiency of both the
automaTtheed p(rreostpotoynpsei vwea)sa nfadbrfiicxaetdeds ytos tceomllse.ctB roetahl-tpimhyes idcaatlaa anndd dciogmitpaalrme othdee lesffhicaivenecbye oenf bcoatlhib trhaet ed
usianugtotmhearteedal -(triemspeodnastiavet)h aantdco fmixeesdf rsoymstetmhes. LBDoRths penhsyosircsa.lT ahneds edvigailtuael smcoodmeilns ghfarvoem betheen lcigalhibtrsaetnesdo rs
using the real-time data that comes from the LDR sensors. These values coming from the light
werereadthroughtheUNOReadcomponentinFirefly.Aftertheprocessesofconstraining,remapping,
sensors were read through the UNO Read component in Firefly. After the processes of constraining,
andsmoothing,thesamedatacanbeusedtofeedtheUNOWritecomponenttocontroltherotationsof
remapping, and smoothing, the same data can be used to feed the UNO Write component to control
theservosinthephysicalmodelandtofeedthedigitalmodelsimultaneously. Therefore,bothmodels
the rotations of the servos in the physical model and to feed the digital model simultaneously.
are interacting together while responding to the real-time data values coming from the four light
Therefore, both models are interacting together while responding to the real-time data values
sensors,asshowninFigure3. Inordertodeterminetheproducedpower(P)ofboththeresponsive
coming from the four light sensors, as shown in Figure 3. In order to determine the produced power
andfixedsystems,andtocalculateanyefficiencyoptimization(%)throughtheautomatedmethod,
(P) of both the responsive and fixed systems, and to calculate any efficiency optimization (%)
the same PV type and size was installed in a fixed manner. Next, the generated power from both
through the automated method, the same PV type and size was installed in a fixed manner. Next, the
photovoltaicinstallationmethods(i.e.,responsiveandfixed)wasrecordedthroughreadingthevoltage
generated power from both photovoltaic installation methods (i.e., responsive and fixed) was
(V) and current (I). Then, the PV cell efficiency optimization of the responsive installation system
recorded through reading the voltage (V) and current (I). Then, the PV cell efficiency optimization of
wascalculated.
the responsive installation system was calculated.

Figure 3. The prototype calibration procedure and real-time data collection.
Figure3.Theprototypecalibrationprocedureandreal-timedatacollection.
2.2. Case Study
2.2. CaseStudy
The case study (Empire World T1) is an office building located in Erbil, Northern Iraq, between
latTituhdeecsa 3se5°s3t0u′ daynd(E 3m7°p1i5r′eNW anodrl dloTng1i)tuisdaens 4o3ffi°2c2e′ banudil d4i5n°0g5l′oEc. aTtheed cilnimEartbei lo,fN Eorrbtihl eisr nchIarraaqc,tebreitzwede en
lataitsu sdeemsi3-a5r◦i3d0 w(cid:48) ainthd lo3n7◦g1, 5h(cid:48)oNt, darnyd sluomngmiteurds easnd43 s◦h2o2r(cid:48)t,a cnodol4 5w◦i0n5te(cid:48)rEs. [T9h].e Tchleim teamtepoefraEtrubriel eisxcceheadrsa c4t3e r°iCz ed
asisne mthie-a hriodttwesitt hmloonntgh,sh iont ,sdurmymsuemr, mwehrislea int ddsrohposr tt,oc o2o °lCw dinutreirnsg[ 9t]h.eT choeldteemst pmeroanttuhrse ienx cweiendtesr4. 3T◦hCe in
theavheortategset hmoounrst hosf itnhes usumnmsheirn,ew pheirl ediatyd arroep asbtoou2t ◦nCinde uhroiunrgs,t hase schooldwenst inm Toanbthles 1i.n winter. Theaverage
hoursofthesunshineperdayareaboutninehours,asshowninTable1.
Table 1. Average annual temperatures and sunshine hours in Erbil [9].
Table1.AverageannualtemperaturesandsunshinehoursinErbil[9].
MONTH Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
AVG MAX TEMP 12 15 19 25 32 39 43 42 38 29 21 14
AVG MMOINN TTEHMP 2 Jan F3 eb M7 ar 1A1 pr 16M ay 21 Jun25 Jul 24 Aug 19S ep 14O ct 8 Nov D4 ec
Cold period Moderate Hot period Moderate Cold
AVGMAXTEMP 12 15 19 25 32 39 43 42 38 29 21 14
AVG HRS
AVGMINTEMP 5 2 6 3 77 8 11 10 16 14 21 14 25 13 24 11 19 8 14 6 8 54
SUNSHINE/DAY
Coldperiod Moderate Hotperiod Moderate Cold
AVGHRS
5 6 7 8 10 14 14 13 11 8 6 5
STUhNeS HEImNEp/iDreA YWorld T1 office building [22] (latitude 36°19′ N, longitude 43°97′ E) is a concrete
structure with glass (outer to inner: 8 mm thick blue-green tempered and heat-soaked, 12 mm
airTsphaeceE,m apnidr e6W mormld tThi1cko fficlceearb uteimldpinegre[d2 2l]ow(la-Eti)t uadned 3c6o◦m19p(cid:48)oNsi,telo anlguimtuidnuem43 ◦(49 7m(cid:48) Em) itshaickconnescsr)e te
cladding for external finishing materials. The building has 27 floors in which the first four floors
structurewithglass(outertoinner: 8mmthickblue-greentemperedandheat-soaked,12mmairspace,
serve as information, office services, a business center, a conference hall, meeting rooms, and a café,
and6mmthickcleartemperedlow-E)andcompositealuminum(4mmthickness)claddingforexternal
while the upper floors constitute offices. The height of each floor is 4 m with a total construction area
finishing materials. The building has 27 floors in which the first four floors serve as information,
of 24,000 m2. The total gross area of each office floors varies between 750 m2 and 1035 m2, as shown in
Figure 4.
Sustainability2017,9,2096 6of22
officeservices,abusinesscenter,aconferencehall,meetingrooms,andacafé,whiletheupperfloors
constituteoffices. Theheightofeachflooris4mwithatotalconstructionareaof24,000m2. Thetotal
grossareaofeachofficefloorsvariesbetween750m2and1035m2,asshowninFigure4.
Sustainability 2017, 9, 2096 6 of 21

Figure 4. Empire World T1 elevation and the plan of office floors [20].
Figure4.EmpireWorldT1elevationandtheplanofofficefloors[20].
Erbil’s extreme conditions in summer and winter require careful considerations when
desigEnrbinilg’s tehxitsr etmypeec oonf dbiutiioldnisnign; shuomwmeveerra, ntdhiws itnotwererr ehqausi rae claarrgefeu gllcaoznesdid fearcaatdioen sinw ahlle nordieensitgantiionngs
twhiisthtyopuet ohfabvuinilgd ianngy; hexotwerenvaelr ,sthhaidsitnogw seyrshtaemsas.l aDrguee gtola ztheed efaxccaedsseivine aslolloarri egnatiant iionn ssuwmitmheoru tanhdav hinegat
alnoyss exinte rwnianlteshr,a dthinisg osfyfisctee mbsu.iDlduinegt ocothnesuemxceess sai vveesroyl alrarggaei naimnosuunmt mofe realencdtrihceitayt lfoosrs iinndwooinr teari,r
tchoisndofifiticoenibnugi,l dwinhgiccho nissu mthees amvaeirny elanregregaym soouunrcteo foefl etchtrei ciptyrofjoecrti.n dCooonrseaqiruceonntldyi,t iocnarinbgo,nw dhiiocxhidise
tehmemissaiionnesn derrgaymsaotuicraclelyo finthcereparsoej,e cwt.hCicohn sseeqvueerneltyly ,acfaferbctosn tdhieo xciidtye’es meinsvsiioronnsmdreanmt, aatincadl lymiankcerse atshee,
wbhuiicldhinsegv ienreeflfyicaieffnetc itns ttheremcist yo’fs eennevrigryo npmerefonrtm,aanndcem, athkeersmthael cboumilfdoirntg, ainndef sfiucsietanitnianbtileirtmy sstaonfdenaredrgs.y
performance,thermalcomfort,andsustainabilitystandards.
2.3. Computer Modelling and Simulations of Energy Performance and Electricity Generation
2.3. ComputerModellingandSimulationsofEnergyPerformanceandElectricityGeneration
Studies on computer modelling and simulations declare that computer simulations play vital
Studiesoncomputermodellingandsimulationsdeclarethatcomputersimulationsplayvital
roles in building design of resident comfort and energy performance through contributing to solving
rolesinbuildingdesignofresidentcomfortandenergyperformancethroughcontributingtosolving
building performance issues [23,24]. Hence, the present study uses OpenStudio® software (NREL,
buildingperformanceissues[23,24]. Hence,thepresentstudyusesOpenStudio® software(NREL,
Washington, DC, USA) [25], which supports complete building energy modelling using
Washington,DC,USA)[25],whichsupportscompletebuildingenergymodellingusingEnergyPlus™
EnergyPlus™ (NREL, Washington, DC, USA) [26]. Developed by National Renewable Energy
(NREL,Washington,DC,USA)[26]. DevelopedbyNationalRenewableEnergyLaboratory(NREL)of
Laboratory (NREL) of the U.S. Department of Energy (DoE), OpenStudio®, along with EnergyPlus™,
theU.S.DepartmentofEnergy(DoE),OpenStudio®,alongwithEnergyPlus™,isavigorousenergy
is a vigorous energy simulation tool that enables energy performance analysis of low-energy
simulationtoolthatenablesenergyperformanceanalysisoflow-energytechnologiesinresidential
technologies in residential and commercial buildings [27,28].
andcommercialbuildings[27,28].
Computer simulation of energy modelling needs substantial knowledge associated with the
Computer simulation of energy modelling needs substantial knowledge associated with the
physical and operational characteristics of the building, as well as precise input data of the building
physicalandoperationalcharacteristicsofthebuilding,aswellaspreciseinputdataofthebuilding
and climate [24,29]. In order to investigate the impact of the proposed integration system, the
andclimate[24,29]. Inordertoinvestigatetheimpactoftheproposedintegrationsystem,thebase-case
base-case energy simulations were accomplished to serve as a baseline reference for comparative
energy simulations were accomplished to serve as a baseline reference for comparative energy
energy performance. Based on the above assumptions, the general features of the computerized
performance. Based on the above assumptions, the general features of the computerized model
model of the T1 building were established for energy performance simulations, as shown in Tables 2
oftheT1buildingwereestablishedforenergyperformancesimulations,asshowninTables2and3.
and 3. The computer modelling was performed only for the floors that are dedicated to serving as
Thecomputermodellingwasperformedonlyforthefloorsthatarededicatedtoservingasoffices.
offices. Each floor is divided into two different thermal zones: one for the office areas and the other
Eachfloorisdividedintotwodifferentthermalzones: onefortheofficeareasandtheotherforcentral
for central service and the circulation core. The office floors are assigned heating, ventilation, and air
serviceandthecirculationcore. Theofficefloorsareassignedheating,ventilation,andairconditioning
conditioning (HVAC)-packaged rooftop of a direct expansion (DX) variable air volume (VAV) units
(HVAC)-packagedrooftopofadirectexpansion(DX)variableairvolume(VAV)unitswithreheats,
with reheats, office equipment loads, and interior lighting loads. Figure 5 illustrates the modelling
officeequipmentloads,andinteriorlightingloads. Figure5illustratesthemodellingandsimulation
and simulation stages with the details and attributes of each stage.
stageswiththedetailsandattributesofeachstage.
Table 2. ASHRAE (American Society of Heating, Refrigerating and Air-Conditioning
Engineers)-based assigned features to the model.
Building Type Space Type Construction Set Schedule Set
189.1-2009-Office- 189.1-2009-Office-WholeBuilding-
Office Bldg 189.1-2009-CZ2-Office
OpenOffice-CZ1-3 Lg Office-CZ1-3 Schedule set
Sustainability2017,9,2096 7of22
Table2.ASHRAE(AmericanSocietyofHeating,RefrigeratingandAir-ConditioningEngineers)-based
assignedfeaturestothemodel.
BuildingType SpaceType ConstructionSet ScheduleSet
189.1-2009-Office-WholeBuilding-Lg
OfficeBldg 189.1-2009-Office-OpenOffice-CZ1-3 189.1-2009-CZ2-Office
Office-CZ1-3Scheduleset
Sustainability 2017, 9, 2096 7 of 21
Table3.ASHRAE-basedbuildingcomponentfeaturesofthemodelandactualfeatures.
Table 3. ASHRAE-based building component features of the model and actual features.
CCoommppoonneenntNt Namame e ConstruCcotniosntr uNctaimoneName ActAucatlu FaleFaetuatruerses
Glass with aluminum frame
Fixed and operable ASHRAAES 1H8R9A.1E-2108099.1 E-2x0t0.9 WExint.dWoiwnd ow Glasswithaluminumframe(8mmthick
Fixedandoperablewindows (8 mblmue t-ghriecekn btleumep-gerreeden+ t1e2mmpmeraeidr v+a 1cu2u mmm
windows ClimateC Zliomnaete 2Z one2
air +va6cmumumlo w+ -6E mtemm ploerwed-Ec lteeamr)pered clear)
ASHRAAES 1H8R9A.1E-2108099.1 E-2x0t0.9 WExatl.l Wall Composite aluminum cladding
WWaalllsls Compositealuminumcladding(4mmthick)
Mass ClMimasasteC lZimonatee 2Z one2 (4 mm thick)
ASHRAAES 1H8R9A.1E-2108099.1 E-2x0t0.9 REoxot.f Roof ReiRnefoinrfcoerdce cdocnocnrcerteet ewwitithhoouutt iinnssuullaattioionn
RRooooff cceeiliilningg
IEAD CIlEimADateC lZimonatee 2Z one2 (200(2 m00mm mthitchkic)k )
ExtSlabECxatrSplaebtC 1a0r1p.e6t m10m1.6 mm ReiRnefoinrfcoerdce cdocnocnrcerteet e(2(20000 mmmm tthhiicckk))a anndd
FFlloooorr ClimateZone1–8 marbletiles(20mmthick)
ClimateZone 1–8 marble tiles (20 mm thick)

Figure5.Thestructureofthemodellingandsimulationprocess.
Figure 5. The structure of the modelling and simulation process.
TThhee iinntteeggrraatteedd rreessppoonnssiivvee sshhaaddiinngg ddeevviiccee iiss aa pphhoottoovvoollttaaiicc ttrraacckkiinngg ssyysstteemm tthhaatt rreessppoonnddss ttoo tthhee
ssuunn’’ss mmoovveemmeenntt ttoo mmaaxximimizizee ththee PPVV efeffificiceinencyc.y .TThhe esisdied elelnegntght hofo tfhteh gelgaslas sesnevnevloeploep oeno enaceha cfhlofloro oisr
2is2.202 m.0. mTh.eT shteusdtyu dexyaemxianmesin tehse tshoeustho,u etahs,te, aasntd,a wnedswt oersitenotraietinotnasti aonnds aenxcdluedxeclsu tdhees ntohrethn foarctahdfea,c daduee ,
tdou ietst omiitnsimmuinmim suomlars oraladriartaidonia tiino nthien stthuedsyt uldocyatloiocna.t iTonh.e Ttwheo-tawxios- atrxaiscktirnagck sinhgadsihnagd dinegvidceesv iacrees
ianrteeginratetegdra twedithw PitVh PcVellcse lolsf omfomnoocnroycsrtyaslltianleli nseilisciolinco tnyptyep ethtahta tisi schchaararcatcetreirziezded bbyy 1155%% mmoodduullee
eeffffiicciieennccyy aanndd aa −−00.4.477%%/°/C◦C tetmempepreartauturer ecoceofeffificiceiennt toof fppoowweer,r ,aass pprreesseenntteedd iinn TTaabbllee 44.. TThhee ddiimmeennssiioonnss
ooff oonnee mmoodduullee aarree sseett ttoo bbee aa ssttaannddaarrdd 11..6644 mm ((ll)) ×× 00..9999 mm ((ww)) aanndd,, ffoorr tthhee ppuurrppoosseess ooff mmiinniimmiizziinngg
mmeecchhaanniiccaall aanndd tteecchhnniiccaall rreeqquuiirreemmeennttss,, ttwwoo PPVV mmoodduulleess aarree mmeerrggeedd ttoo ccoonnssttrruucctt oonnee aauuttoommaatteedd
sshhaaddiinngg eelleemmeenntt..A Ag agpaopf 1o.0f 81m.08is mlef tibs etlwefet ebnettwwoeerens ptownos ivreessphoandsinivge dsehvaicdeisn,gth edreevbiycems,i ntihmeirzeibnyg
mthienirmiskizoinfgs etlhfe-s rhiaskd ionfg sseblfe-tswhaedenineglse mbeetnwtse.enFi geluermee6nmtsa. nFiifgeusrtse t6h emPaVnifoepsatsq utheea PreVa oapnadqgulea sasreaar eaanodf
gelaacshs flaroeoar oofn etahceh sftluodorie odno trhiee nsttautdioiends. oTrhieenrteaftoiroen,st.h TehteorteafloPrVe, athreea tofotarla PllV2 3aroefafi fcoerfl aollo 2rs3 iosfcfiaclec uflloaoterds
iass c1a5lc6u8l.a4tmed2 ,aass 1s5h6o8w.4 nmi2n, aFsi gsuhroew7n. in Figure 7.
TTaabbllee 44.. MMoodduullee ttyyppee ooppttiioonnss aanndd ffeeaattuurreess [[3300]]..
Type Approx. Efficiency Module Cover Temperature Coefficient of Power
Type Approx.Efficiency ModuleCover TemperatureCoefficientofPower
Standard (crystalline silicon) 15% Glass −0.47%/°C
PrSetmaniduamrd (c(rcyrysstatalllilinnee ssiilliiccoonn)) 1195%% Anti-refGlelcatsivse −0−.305.%47/%°C/ ◦C
Premium(crystallinesilicon) 19% Anti-reflective −0.35%/◦C

Figure 6. Photovoltaic opaque area of each floor on the south, east, and west orientations.
Sustainability 2017, 9, 2096 7 of 21
Table 3. ASHRAE-based building component features of the model and actual features.
Component Name Construction Name Actual Features
Glass with aluminum frame
Fixed and operable ASHRAE 189.1-2009 Ext. Window
(8 mm thick blue-green tempered + 12 mm
windows Climate Zone 2
air vacuum + 6 mm low-E tempered clear)
ASHRAE 189.1-2009 Ext. Wall Composite aluminum cladding
Walls
Mass Climate Zone 2 (4 mm thick)
ASHRAE 189.1-2009 Ext. Roof Reinforced concrete without insulation
Roof ceiling
IEAD Climate Zone 2 (200 mm thick)
ExtSlabCarpet 101.6 mm Reinforced concrete (200 mm thick) and
Floor
ClimateZone 1–8 marble tiles (20 mm thick)

Figure 5. The structure of the modelling and simulation process.
The integrated responsive shading device is a photovoltaic tracking system that responds to the
sun’s movement to maximize the PV efficiency. The side length of the glass envelope on each floor is
22.0 m. The study examines the south, east, and west orientations and excludes the north facade, due
to its minimum solar radiation in the study location. The two-axis tracking shading devices are
integrated with PV cells of monocrystalline silicon type that is characterized by 15% module
efficiency and a −0.47%/°C temperature coefficient of power, as presented in Table 4. The dimensions
of one module are set to be a standard 1.64 m (l) × 0.99 m (w) and, for the purposes of minimizing
mechanical and technical requirements, two PV modules are merged to construct one automated
shading element. A gap of 1.08 m is left between two responsive shading devices, thereby
minimizing the risk of self-shadings between elements. Figure 6 manifests the PV opaque area and
glass area of each floor on the studied orientations. Therefore, the total PV area for all 23 office floors
is calculated as 1568.4 m2, as shown in Figure 7.
Table 4. Module type options and features [30].
Type Approx. Efficiency Module Cover Temperature Coefficient of Power
SustainSatbainlidtyar2d0 1(c7r,y9s,t2a0ll9in6e silicon) 15% Glass −0.47%/°C 8of22
Premium (crystalline silicon) 19% Anti-reflective −0.35%/°C

Figure 6. Photovoltaic opaque area of each floor on the south, east, and west orientations.
Figure6.Photovoltaicopaqueareaofeachflooronthesouth,east,andwestorientations.

Sustainability 2017, 9, 2096 8 of 21

Sustainability 2017, 9, 2096 8 of 21

Figure 7. Schematic view of the case-study building with PV-integrated responsive shading devices.
Figure7.Schematicviewofthecase-studybuildingwithPV-integratedresponsiveshadingdevices.
Figure 7. Schematic view of the case-study building with PV-integrated responsive shading devices.
Utilizing the EnergyPlus™ energy management system (EMS), multiple overlapping surfaces
are dUeUftiitnliielzidzini n(gSght htahedeiE nEngne: reBgrugyyiPlPdluliuns™sg™: De neenetraegirlgyeydm )m ainna natgahgeeme smaemnentets ylsoysctseatmetimo(n E(, EMbMuSt)S ,)w,m imtuhul tlditpiifplfeleeor evonevtre ltraillpatp papinnidng gas uzsuirmfrafucaetchse s
aaanrergeld edesfie (fnFiniegdeud(r Se(hSs ha8da adinnidngg :9:B) .Bu EuiMlidldiSni n(gSg:u:D rDfeaetcateai liEelexddt) )Si noinlta htrh eBese saaammme Cel ooloscicanateitoi oonfn, ,Ib nbucutidtw ewnitichteh d Adifniffgeferleer)en nitnttd itliitcltaa tnaendsd ta hzaeizm mimuoutshtth
apanenrgpgleelesnsd( (FiFcigiuguluarrre esssu 88r faaanncdde 99t)o).. EtEhMMeS Ss (uS(nSuu rafranfacdec e EthExrtxo StuoSglohalr a oBrveBearemrai mdCionCsgio ntsehi neoeifr IontfrcaIindnsecpindacereen AncecnygA lsenc)g hilneedd)uiicnlaedt,e itsch atethe esm mtohosets t
mppeoresprtpepneendrdipcieucnuladlrai rcs uuslruafrarfcsaeuc ceraf atnoc eb tetho seet hts aeusns fu uanlnlaydn odtphtarhqoruuogeu hag nhodov tvehreerri rrdiedisnitng ag st thfhueeilrilry t ttrrraaannnssspppaaarrreeennncctyy a tss ccthhheee ddmuuolleem,, tethnhete.m Tmohosists t
psipemreprupelanetndedisc iuctuhlaelar ris nsufurlurffaeacncecee cc aaonnf bbtehe ess eeatt uaatsso fmufulallytley odop psahqaaquduei eanngad nd dtehvtehi rceeesrset soatsn a fulsolfwluye ltlrryianntgrsa ptnhasrepe ancrote oantlt itnhaget tmlhoaoedmmse onomtf. eTthnheti. s
Tbsuhiiimlsdusiinlmagt ueisnla ttthhesee tsihunemfliunmeflneurc eesn eocaefs ootnhf.et h aeuatuotmomateadte dshsahdaidnign gddeveivciecse soonn lloowweerriningg tthhee ccoooolliinngg llooaaddss oofft hthee
bbuuilidldininggi nint hthees usummmmerers esaesaosnon. .

Figure 8. Defined tilt and azimuth angles for each orientation.
FFigiguurere8 .8.D Defiefninededt itlitlta nandda zaizmimuuththa nangglelsesf ofrore aecahcho roireinetnattaitoino.n.

Figure 9. Simulated optimal tilt and azimuth angles for the south, east, and west façades.
Figure 9. Simulated optimal tilt and azimuth angles for the south, east, and west façades.
To avoid complicated EMS scripting for calculating the generated electricity from the
PV-intTeog raatveodi dtw coo-maxpisli ctaratecdk inEgM eSle mscerniptst,i nLga dfyobr ucga l[c3u1l]a t(ionpge nt-hseo ugrceen eernavteirdo nemleecntrtiacli tpyl ufgrionms fothr e
GPrVas-sinhtoepgpraetre 3dD t)w iso u-asxeids . tTrhacek minogd eellleimnge notfs a, uLtaodmyabtuedg p[3a1n]e l(so wpeans- csoonudrcuec teendv uirsoinngm Genrtaasls hpolupgpienrs 3 fDo r
aGndra, stshhroopupgehr 3eDm)p ilso uysinedg . LThade ymboudge lRliennge owfa abuletos,m tahtee da pmaonuelnst woafs gcoennedruactetedd eulseicntgri cGitrya sfsrhoomp peear c3hD
oarinedn,t atthioronu cgahn beem ppelorcyeiinvge dL. aIdn yebauchg oRreiennetwataiobnle,s 1, 0t hdeif faemreonut notp toimf agle annegraletes dw eerleec rtreiacliitzye df rfoomr beoathch
orientation can be perceived. In each orientation, 10 different optimal angles were realized for both
Sustainability 2017, 9, 2096 8 of 21

Figure 7. Schematic view of the case-study building with PV-integrated responsive shading devices.
Utilizing the EnergyPlus™ energy management system (EMS), multiple overlapping surfaces
are defined (Shading: Building: Detailed) in the same location, but with different tilt and azimuth
angles (Figures 8 and 9). EMS (Surface Ext Solar Beam Cosine of Incidence Angle) indicates the most
perpendicular surface to the sun and through overriding their transparency schedule, the most
perpendicular surface can be set as fully opaque and the rest as fully transparent at the moment. This
simulates the influence of the automated shading devices on lowering the cooling loads of the
building in the summer season.

Sustainability2017,9,2096 9of22
Figure 8. Defined tilt and azimuth angles for each orientation.

Figure 9. Simulated optimal tilt and azimuth angles for the south, east, and west façades.
Figure9.Simulatedoptimaltiltandazimuthanglesforthesouth,east,andwestfaçades.
To avoid complicated EMS scripting for calculating the generated electricity from the
PV-inTtoegaravtoeidd twcoom-apxliisc attreadckiEnMg Selesmcreipnttisn, gLafdoyrbucagl c[u3l1a]t i(nogpetnh-esougercnee reantevdiroenlmecetnritcailt yplfurgoimns tfhoer
GPVra-isnshteogprpateerd 3Dtw) ois- auxsiesdt.r Tahckei mngodeelellminegn otsf, aLuatodmybautegd[ p31a]ne(olsp wena-ss ocounrcdeucetnevdi ruosninmge Gntraalssphloupgpinesr 3foDr
aGnrda,s sthhorpopuegrh 3eDm)pislouysiendg. LTahdeymbuogd eRlleinngewoafbaluetso, mthaet edampoaunnelts owf agsecnoenrdatuecdt eedleucstirnicgitGy rfarsosmho peapcehr
o3Drieanntadt,iothn rcoaung bhee pmeprcloeiyviendg. LIna deyacbhu gorRieennteawtioanb,l e1s0, dthifefearmenotu onpttiomfagle annegraletesd weelreec trreiaciltizyefdr ofmor ebaocthh
orientationcanbeperceived. Ineachorientation,10differentoptimalangleswererealizedforbothtilt
(between0◦ and90◦)andazimuth(east: between0◦ and180◦;south: between90◦ and270◦;andwest:
between180◦ and360◦)anglesusingLadybug_TiltandOrientationFactor(TOF),asdemonstratedin
Figures8and9.Figure10manifeststheprocessofdefiningtheoptimalanglesandthesimulatedangles
foreachorientation. UsingtheLaybug_PhotovoltaicsModule(PhotovoltaicsModule),themodule
settingsweredecidedtobeanormalcrystallinesiliconwith15%moduleefficiencyand−0.47%/◦C
temperature coefficient (Table 4). Then, the system size was defined through feeding EnergyPlus
WeatherFilesdata(Tabriz.epwisutilizedastheclosestavailableweatherstationtoErbil),theintended
orientation, the PV surface, the available optimal tilt and azimuth angles, and the PV module
to the Ladybug_PV SWH System Size (PV_SWH_SystemSize). The Ladybug_Sunpath Shading
(SunpathShading)componentcalculatestheannualshadingofPVmodulesduetothebuildingand
shadingdevices. Thiscomponenttakes.epwFile,analysisGeometry,context,andACenergyPerHouras
inputsandoffersseveralcriticaloutputssuchasShadedSolarRadiationPerHour,Sep21toMar21Shading,
Mar21toSep21Shading, annualShading, hours, and so on. Therefore, the building geometry and
all shading elements were fed to the Context input to define any obstacles that may cause
shadings. To calculate total losses of the system and DC to AC derate factor, the annualShading
outputoftheSunpathShading(SunpathShading)componentwasfedtotheannualShading_input
of Ladybug_DCtoACderateFactor (Figure 10). Then the DCtoACderateFactor output was fed to
Photovoltaics Surface (Photovoltaics Surface) component to calculate amount of electrical energy
(kWh/year)thatcanbeproducedbythePVsurfacesofeachfaçade. Figure11manifeststheSunpath
Shadingdiagramof,respectively,south,east,andwestorientationsandtheirannualshadingstatus.
Sustainability 2017, 9, 2096 9 of 21
tilt (between 0° and 90°) and azimuth (east: between 0° and 180°; south: between 90° and 270°; and
west: between 180° and 360°) angles using Ladybug_Tilt and Orientation Factor (TOF), as
demonstrated in Figures 8 and 9. Figure 10 manifests the process of defining the optimal angles and
the simulated angles for each orientation. Using the Laybug_Photovoltaics Module
(PhotovoltaicsModule), the module settings were decided to be a normal crystalline silicon with 15%
module efficiency and −0.47%/°C temperature coefficient (Table 4). Then, the system size was
defined through feeding EnergyPlus Weather Files data (Tabriz.epw is utilized as the closest
available weather station to Erbil), the intended orientation, the PV surface, the available optimal tilt
and azimuth angles, and the PV module to the Ladybug_PV SWH System Size
(PV_SWH_SystemSize). The Ladybug_Sunpath Shading (SunpathShading) component calculates
the annual shading of PV modules due to the building and shading devices. This component takes
.epwFile, analysisGeometry, context, and ACenergyPerHour as inputs and offers several critical
outputs such as ShadedSolarRadiationPerHour, Sep21toMar21Shading, Mar21toSep21Shading,
annualShading, hours, and so on. Therefore, the building geometry and all shading elements were
fed to the Context input to define any obstacles that may cause shadings. To calculate total losses of
the system and DC to AC derate factor, the annualShading output of the Sunpath Shading
(SunpathShading) component was fed to the annualShading_ input of
Ladybug_DCtoACderateFactor (Figure 10). Then the DCtoACderateFactor output was fed to
Photovoltaics Surface (Photovoltaics Surface) component to calculate amount of electrical energy
S(kusWtaihna/ybieliatyr)2 0t1h7a,t9 ,c2a0n96 be produced by the PV surfaces of each façade. Figure 11 manifests the Su1n0poaft2h2
Shading diagram of, respectively, south, east, and west orientations and their annual shading status.
Figure 10. Grasshopper and Ladybug definition of the PV-integrated shading devices.
Figure10.GrasshopperandLadybugdefinitionofthePV-integratedshadingdevices.

Sustainability 2017, 9, 2096 10 of 21

Figure 11. Ladybug_Sunpath Shading diagram for the (a) south, (b) east, and (c) west façades.
Figure11.Ladybug_SunpathShadingdiagramforthe(a)south,(b)east,and(c)westfaçades.
3. Results and Discussions
3. ResultsandDiscussions
The findings of this research were obtained from four sequencing study phases. Accordingly,
Thefindingsofthisresearchwereobtainedfromfoursequencingstudyphases. Accordingly,
the results are presented and discussed. The first stage involved maximizing the efficiency of PV
the results are presented and discussed. The first stage involved maximizing the efficiency of PV
through the integration method. In the second stage, the base case building was modelled and
through the integration method. In the second stage, the base case building was modelled and
simulated to be used as reference data. Then, the building performance simulation was repeated
simulated to be used as reference data. Then, the building performance simulation was repeated
after the system integration of PV-integrated responsive shading devices to explore the impact of
after the system integration of PV-integrated responsive shading devices to explore the impact of
this integration system on energy consumption. Finally, the amount of produced electricity from the
application of the PV-integrated system on the case study building was calculated.
3.1. Calculation of the PV Efficiency
The initial objective of this study was to maximize the output efficiency of photovoltaic cells. A
prototype-based model was developed to address this intention. In order to compare the output
power (P) produced from both the dual-axis tracking (responsive) technique and the fixed system
(non-adjustable), both methods were tested with real-time data. Using the same PV type
(monocrystalline silicon) and size (125 mm × 125 mm) as the automated method, the south-facing
fixed installation was tilted at 54° as an optimum annual average tilt angle for the experiment
location [32]. This experiment was conducted in the specific climatic conditions of Erbil from the
time period between 07:00 and 18:00 on 16 July 2016. The current (I) and voltage (V) produced by
both methods were measured through the DC ammeter/voltmeter. Then the power (P) is calculated
and recorded for both installation systems in Table 5.
(cid:1842)((cid:1875))=(cid:1835)((cid:1853))×(cid:1848)((cid:1874)) (1)
A comparative graph was designed to show the difference in efficiency between the responsive
and fixed systems, as shown in Figure 12. Using the relative difference equation (Equation (2)), the
calculation results of the total produced power (P) from both installation methods indicate that the
responsive tracking system is more efficient by approximately 36.8% in comparison to the fixed
installation, considering the location of the experiment (Erbil). The graph manifests that the fixed
installation is only efficient at noontime when the sun is perpendicular to the panel. Conversely, the
tracking system is efficient during nearly the whole day as it keeps the panel perpendicular to the
sun at all times.
|∆(cid:1842)|
(cid:1831) = ×100(%)
∑(cid:1842) (2)
2
where E is the PV efficiency and P is the different amount of power generated from both fixed and
responsive installation systems.