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PolicyResearchWorkingPaper10510
PowerConstraintsandFirm-LevelTotalFactorProductivityinDevelopingCountries
AblamEstelApeti
AlphaLy
DevelopmentEconomics
DevelopmentResearchGroup
June2023
ProducedbytheResearchSupportTeam
PolicyResearchWorkingPaper10510
Abstract
theseverityofself-reportedpowerconstraintsorobstaclesbyfirmsandthemagnitudeofrevenue-basedtotalfactorproductivityloss.Theresultsalsoindicatethattheeffectofpoweroutagesonfirm-levelrevenue-basedtotalfactorproductivitycouldbeinfluencedbythestageofeconomicdevelopment(low-incomecountries,lower-middle-incomecountries,upper-middle-incomecountries),andtheabil-ityoffirmstoengageinresearchanddevelopmentandpurchasebackupgenerators.Thesefindingssuggestthattoensureeconomicdevelopment,thegovernmentshouldprovideastablepowersupplythatcanmitigatethenegativeshocksfacedbymanufacturingfirmsandenhancetheirproductivityandcompetitiveness,allowingthemtodriveeconomicgrowth.
Thispaperanalyzestheeffectsofpoweroutagesandcon-
straintsonmanufacturingfirms’revenue-basedtotalfactor
productivityindevelopingcountries.Theempiricalanalysis
isbasedontheWorldBankEnterpriseSurveysdatasetfor
84countriesover2006–2019.Thepaperstartsbyshow-
ingstatisticallythatfirmsfacingpoweroutagesdifferand
operateinverydifferentenvironmentscomparedtofirms
notfacingpoweroutages,underliningapotentialnonran-
domissueofthetreatmentvariable.Thematching-based
approach(entropybalancing)isdesignedtocontainthis
typeofbias.Itshowsthatpoweroutagesnegativelyand
significantlyaffectfirm-levelrevenue-basedtotalfactorpro-
ductivity,witha9percentlowerunconditionalaverage
productivityforexposedfirmscomparedtononexposed
firms.Moreover,theestimatessuggestaconnectionbetween
ThispaperisaproductoftheDevelopmentResearchGroup,DevelopmentEconomics.ItispartofalargereffortbytheWorldBanktoprovideopenaccesstoitsresearchandmakeacontributiontodevelopmentpolicydiscussionsaroundtheworld.PolicyResearchWorkingPapersarealsopostedontheWebat/prwp.Theauthorsmaybecontactedataly6@oraapeti@.
ThePolicyResearchWorkingPaperSeriesdisseminatesthefindingsofworkinprogresstoencouragetheexchangeofideasaboutdevelopmentissues.Anobjectiveoftheseriesistogetthefindingsoutquickly,evenifthepresentationsarelessthanfullypolished.Thepaperscarrythenamesoftheauthorsandshouldbecitedaccordingly.Thefindings,interpretations,andconclusionsexpressedinthispaperareentirelythoseoftheauthors.TheydonotnecessarilyrepresenttheviewsoftheInternationalBankforReconstructionandDevelopment/WorldBankanditsaffiliatedorganizations,orthoseoftheExecutiveDirectorsoftheWorldBankorthegovernmentstheyrepresent.
PowerConstraintsandFirm-LevelTotalFactorProductivityinDevelopingCountries*
AblamEstelApeti†andAlphaLy‡
JELClassification:L94,D24,O10
Keywords:Powerconstraints,Productivity,Developingcountries
*WethankRajaChakir(INRAE),Jean-LouisCombes(LEO-UCA),AnnaCreti(ParisDauphine),CarolynFischer(TheWorldBank-DECSI),MeganElizabethLang(TheWorldBank-DECSI),andAlexandruMinea(LEO-UCA)fortheirhelpfulcommentsandsuggestions.WearegratefultotheWBGAfricaFellowshipProgramorganizingteam.
†AblamEstelApeti:UniversityofGttingen,Gttingen,Germany,UniversitClermontAuvergne,Universitd’Orlans,LEO,TheWorldBankGroup,E-mail:ablamestel.apeti@uca.fr.
‡AlphaLy(CorrespondingAuthor):ParisDauphineUniversity,ClimateEconomicsChair,ChaireEIEA(MinesParis-PSL&UM6P),EnergyandProsperityChair,TheWorldBank-DECSI,E-mail:aly6@/alpha.ly@dauphine.eu
2
1Introduction
Lowlevelsofinfrastructuredevelopmentandpoorqualityserviceswithinacountrycanincreaseproductioncostsfordomesticfirmsanddiverttheirtechnologicalchoicestosub-optimalsolutions.Thisreducestheirlevelofcompetitivenesscomparedtoforeigncompetitorsingeneral.Furthermore,theeconomicliteraturesuggeststhatbetterpowerinfrastructuresignificantlystimulateseconomicgrowthandimprovesarangeofdevelopmentoutcomes.However,indevelopingcountries,firmsgenerallyhavedifficultyconnectingtothepowergridor,whentheyareconnected,theyfacefrequentscheduledorunscheduledpoweroutages(
Alam
,
2013
).Voltagefluctuationsandthefrequencyofpoweroutagesthereforeleadtomateriallossesandhaveanegativeeffectonmanufacturingcostsandproduction.
Asdriversofeconomicgrowth,amajorpartofthefirmsinthesedevelopingcountriescitepowerasthemajorobstacleoroneofthemainconstraintstotheiractivities(
Asieduetal.
,
2021
).Indeed,poweris
thesecondmostimportantconstraintafteraccesstofinance.Tworegionsareparticularlyaffected,namelySouthAsiaandSub-SaharanAfrica.Infact,about45.9%offirmsinSub-SaharanAfricaand41.2%offirmsinSouthAsiareportthatpowerisamajororsevereconstrainttotheiroperations.Theissueofpowerthusappearstobeofgreaterconcerntothesefirmsthanmanyotherissuessuchascorruptionandtransportinmostoftheseregions.
Giventhemajorroleofmanufacturingfirmsindevelopingcountriesandthegradualimprovementoffirm-leveldataavailabilityandquality,arecentliteratureisemergingontheempiricalassessmentoftheeffectofpowerconstraintsonfirms’performance.However,thisliteratureonpowerconstraintsandfirms’productivityisstillscarceandtheresultsremainratherinconsistentwhencomparedtoeachother.Forexample,somestudiesfindastatisticallysignificantnegativeeffectoftheseconstraintsontheperformanceoffirms(
HardyandMcCasland
,
2021
;
Abebereseetal.
,
2021
),otherstudiesfindastatisticallysignificantbutweakeffect(
GraingerandZhang
,
2017
)andstillothersdonotfindastatisticallysignificantrelationshipbetweenthesepowerobstaclesandtheproductivityoffirms(
Scottetal.
,
2014
).Thislackofconsistencyinthepreviousresultsfromtheliteraturecouldreflectthepotentiallimitationsofthedifferentempiricalapproachesadoptedinthisliteraturesofar.Forexample,
Xiaoetal.
(
2022
)considerpoweroutagesorconstraintsasacompletelyexogenousexplanatoryvariable.Meanwhile,authorslike
Fisher-Vandenetal.
(
2015
);
Allcottetal.
(
2016
);
Coleetal.
(
2018
)or
Elliottetal.
(
2021
)considerthisvariableaspotentiallyendogenousandproposeaninstrumentalvariablestechniquebasedonvariationsinthepowersupplyfromhydroelectricgenerationasaninstrument.
Thispapercontributestotheempiricalliteratureonthepotentialeffectsofpoweroutagesorconstraintsonfirm-levelTFPbyproposinganewmatching-basedapproach(EntropyBalancing)andbyextendingthepreviousresultsfromtheliteraturetothedegreeofseverityofthepowerconstraints.First,contraryto
Xiao
etal.
(
2022
)whopresentthepoweroutagesvariableasanexogenousenergyshock,weshowstatisticallythattheoutagestreatmentvariableisnotrandomformanufacturingfirmsindevelopingcountries.Second,inordertocompensateforthelimitslinkedtotheinstrumentationtechniquebythehydroelectricvariableinsomeanalysisofthisliterature(asin
Fisher-Vandenetal.
,
2015
;
Allcottetal.
,
2016
;
Coleetal.
,
2018
;
Elliottetal.
,
2021
)andtoproperlyaccountforpotentialendogeneitywithrespecttoexposuretopowerconstraints,butalsotoaddressthelackofabalancedpanelstructure(surveydata),weuseamatching-basedapproach(EntropyBalancing).Ouranalysisisbasedontheideathatexposuretoconstraintsrepresents
3
atreatment.Thefirmsexposedtotheconstraintsconstitutethetreatmentgroup,theunexposedfirmsconstituteapotentialcontrolgroup.Third,weestablishastronglinkbetweentheseverityofself-reportedpowerconstraintsorobstaclesbyfirms(minor,moderate,major,severe,andbiggest)andthemagnitudeofproductivitylossforfirms.Inotherwords,thegreaterthelevelofpowerconstraintsself-reportedbyafirm,thegreatertheeffectoftheseconstraintsonitsproductivity,andviceversa.
Broadly,ourapproachshowsthattheoveralleffectofpoweroutagesonrevenue-basedtotalfactorproductivity(TFPR)isnegativeandstatisticallysignificant.Additionally,weshowthatothermechanismssuchastheacquisitionofback-upgenerators,orinvestmentinR&Dallowfirmstofightagainstthesevereconstraintsencounteredinthepowersector.Wealsoshowthatconstraintsinthepowersectoraffectfirmrevenue-basedtotalfactorproductivitymainlythroughthechannelofnon-optimalreorganizationoffirmoperations(reducedcapacityutilization)andthroughthechannelofproductionlossesduetopoweroutages.
Therestofthepaperisasfollows:theliteraturereviewinsection
2
,thetheoreticalframeworkinsection
3
,dataandmodelinsection
4
,empiricalresultsinsection
5
andsection
6
concludes.
2Relatedliterature
Someanalyseshavefocusedontheeffectofinputsmarketconstraintsonproductivity(Prescott
,
2002
;
HsiehandKlenow
,
2009
;
Jones
,
2011
).Theseanalysessuggestthatinputmarketconstraintspreventtheachievementofanefficientallocationofresources,thusreducingtotalfactorproductivity.Inthesamevein,
Brandtetal.
(
2013
)findthatTFPlossesduetoinputmarketconstraintsarestillhighinmanycountries.Morespecificallyinourfieldofresearch,energymarketconstraintsarealsoassessed.Indeed,
Shiand
Sun
(
2017
)findthatenergypriceinstabilitynegativelyaffectsoutputgrowthintheshortandlongrun.Asfor
Bernanke
(
1983
),heshowsthatuncertaintyaboutenergypricescaninducefirmstopostponetheirinvestmentdecisions,thusleadingtoadeclineinoveralloutput.Similarly,
ElderandSerletis
(
2009
)suggestthatoilpriceuncertaintymaytendtoreinforcethenegativeresponseofproductiontooilshocks.Finally,
Chengetal
.(
2019
)showthatanincreaseinoilpricevolatilityreducesrealGDPandinvestment,whileadecreasestimulatestheeconomy.
Withrespecttopowersectorconstraints,
Coleetal.
(
2018
)findthatpoweroutageshaveanegativeandsignificanteffectonfirmsalesin14Africancountries.Theeffectfoundislargerwhenendogeneityistakenintoaccount.
1
Theyalsofindthatpoweroutagesaffectfirmprofitsandtotalfactorproductivity.Furthermore,alsousingahydro-instrumentalvariablestrategy,
Elliottetal.
(
2021
)showthatVietnamesefirmswithlessreliablepowerhavelowerproductivityin2005and2015.Theyconcludethatreducingthelengthofpoweroutagesby1%wouldhaveincreasedoverallrevenuesby4.66billionUSD.Inthesamelineofinstrumentalvariables,
Allcottetal.
(
2016
)alsousechangesinpowersupplyfromhydroelectricgenerationasaninstrumenttoestimatetheeffectofpoweroutagesontheIndianmanufacturingsector.Finally,asimilarapproachistakenby
Fisher-Vandenetal.
(
2015
)whoexaminetheeffectsofpoweroutagesonfirmperformanceinChina.
Meanwhile,theeconomicliteratureremainsrelativelywell-suppliedontheothercommondeterminantsoffirm-levelperformance.Amongthesedeterminants,wecanmentioninternationaldevelopmentaid,fi-nancialinclusion,bankconcentration,financialinnovation,inflation,ortaxation.Internationalaidisakey
1Useofahydro-instrumentalstrategy.
4
factorinimprovingtheperformanceoffirmsbyalleviatinginfrastructureandfinancingconstraintsinde-velopingcountries.Inthissense,
ChauvetandEhrhart
(
2018
)findapositiveeffectofforeignaidonthegrowthoffirms’sales.Furthermore,
ChauvetandJacolin
(
2017
)findthatfinancialinclusion,i.e.thedis-tributionoffinancialservicesinfirms,hasapositiveeffectonfirmgrowth.Thispositiveeffectisamplifiedwhenthereisgreatercompetitionbetweenbanks.Inthesamevein,
Leeetal.
(
2020
)showthatfinancialinclusionhelpsfirmstoincreasetheirsalesgrowth.Ontheotherhand,theyparadoxicallyfindthatfinan-cialinnovationhasanegativeeffectonthegrowthrateoffirms’sales.Intheirpaper,
Bambeetal.
(
2022
)showthatinflationtargetingincreasesthegrowthandproductivityoffirmsintargetedcountriescomparedtonon-targetedcountries.Indeed,inflationtargetingimprovestheperformanceofdevelopingcountriesbyreducingthelevelandvolatilityofinflation(
LinandYe
,
2009
).Finally,
ChauvetandFerry
(
2021
)showthattaxrevenuesboosttheperformanceoffirmsthroughthefinancingofessentialinfrastructureforbusinessdevelopment.
Inthispaper,wemainlycontributetothisliteratureontheeffectsofpoweroutagesorconstraintsbyproposinganewmatching-basedapproach(EntropyBalancing)andbyextendingthepreviousresultsfromtheliteraturetothedegreeofseverityofthepowerconstraints.
3Theoreticalframework
Themainpurposeofthistheoreticalframeworkistwofold.First,wehighlightthedifficultyofdirectlydrawingconclusionsabouthowenergyshockswouldaffectfirm-leveltotalfactorproductivityfromathe-oreticalframework.Thesecondmainobjectiveistoestablishtheoreticallythatproductivitylossincreaseswiththeseverityofenergyconstraintsfacingmanufacturingfirms.
Althoughsomeofthestudiesinthisliteraturepointoutthateconomicgrowth,forinstance,decreasesintheeventofanenergyshock(
Chengetal
.,
2019
;
Sadorsky
,
1999
),weshowinthistheoreticalframe-workthatthiscouldhaverathercontrastingeffectsonthetotalfactorproductivityofmanufacturingfirmsdependingonthemarketstructure.Sincepowerconstraintsareanimportantmanifestationofinputmarketdistortion,ourtheoreticalframeworkiscloselyrelatedtotheliteratureontherelationshipbetweeninputmarketdistortionandfirm-leveltotalfactorproductivity.
Thistheoreticalframeworkofintermediategoodsandoutputpriceadjustmentcausedbyanenergyshockisbasedonthatof
HsiehandKlenow
(
2009
)and
Xiaoetal.
(
2022
).Wederivetheexpressionfortotalfactorproductivityatthefirm-levelandanalyzetheeffectofenergyshocksonfirm-levelTFP.
Weassumemonopolisticcompetitionwithheterogeneousfirmsthatfacedifferentdegreesofenergyconstraints.Indeed,thereareseveralreasonswhyweconsiderpowerconstraintstobefirm-specificratherthansector-specificinthisframework.First,thepowerinfrastructureofacountryorregioncanvaryconsiderablyintermsofreliabilityandquality.Somefirmsmaybelocatedinareaswithbetterpowerinfrastructure,whileothersmaysufferfrequentconstraintslikeoutagesduetoinadequateinfrastructureormaintenance.Second,somefirmsmayhaveinvestedinbackupgeneratorsoralternativepowersourcestomitigatetheimpactofpowerconstraints.Thesefirmswouldbelessaffectedbygeneraldisruptionstothepowersupplythanthosewithoutsuchback-upsystems.Third,firmsinthesamesectormayhavedifferentoperationalrequirementsandproductionprocesses.Somefirmsmaybehighlydependentonacontinuouspowersupply,suchasthoseinvolvedinrefrigerationorotherelectricity-intensiveoperations.Ontheother
5
hand,somefirmsmayhavemoreflexibleproductionprocessesthatcanadapttotemporarypowersupplyinterruptions.Finally,firmsmayadoptdifferentmechanismstocopewithpowerconstraints.Forinstance,somefirmsmayadjusttheirproductionschedules,switchtooff-peakhoursorimplementenergy-savingmeasuresduringoutages,helpingthemtominimizethenegativeimpactofpowerdisruptions.
Inafullycompetitivefinaloutputmarket,thereisasinglefinalproductY,anditisaggregatedfromtheoutputYsofSmanufacturingindustries(orbranches)bythefollowingproductionfunction:
SS
s=1s=1
Y=∏Ysθs,where∑θs=1(1)
whereθsisanoutputelasticityparameterforindustrys.Minimizingproductioncostsimplies:
PsYs=θsPY(2)
PsisthepriceoftheoutputYsoftheindustrys,andthepriceofthefinalproductisP≡∏=1()θs.The
outputYsoftheindustrysistheCESaggregateofMstypesofdifferentiatedproducts:
σ
(3)
Ys=(Ysiσ1)σ−1
whereσistheelasticityofsubstitutionbetweenthedifferentiatedproductswithintheindustrys.
TheproductionfunctionofeachdifferentiatedproductisgivenbyaCobb-Douglasfunctionofthefirm’sTFPandthreeproductioninputs,includingcapital,laborandenergy:
Ysi=AsiKsLE−αs−βs
(4)
whereαsdenotesthecapitalshareofindustrys,βsdenotesthelaborshareofindustrys,(1−αs−βs)denotestheshareofintermediateproductsortheshareofenergyofindustrys,andAsidenotesthelevelofTFPoffirmi.Notealsothatthisframeworkallowsinputsharestodifferbetweendifferentindustriesbutnotbetweenfirmsinthesameindustry.
TheprofitmaximizationprogramformonopolisticallycompetitivefirmswithrespecttoKsi,Lsi,andEsi
isasfollows:
maxπsi=PsiYsi−rKsi−wLsi−(1+τEsi)PEEsi
(5)
s.t.Ysi=AsiKsiαsLsiβsEsi1−αs−βs
whererrepresentsthepriceofcapital,wrepresentsthelabourcost,PErepresentsthecostofintermediateinputs,i.e.energy.τEsirepresentstheenergyconstraints(increaseinthecostofenergy,poweroutagesleadingtoadditionalcostsforback-upgenerators,increaseinlossesforfirms,etc.)facingarepresentativefirmi.
Themaximizationoftheprofit(
5
)usingtheLagrangianmethodofoptimizationcombinedwiththefirstorderconditionsyields:
6
TheanalysisoftheeffectofenergyconstraintsτEsiontheequation(
10
)revenue-basedTFPleadsto:
'''λAsiαsKsiαs−1LsiβsEsi1−αs−βs−r=0
〈Ksi=rβs×Lsi
w1−αs−βs1
wαs
'(Esi=PEβs(1+τEsi)×Lsi
whereλ=Psi
(6)
(7)
(8)
Bysubstitutingtheequations(
7
)and(
8
)intotheequation(
6
),weobtainthestandardconditionthatthefirm’soutputpriceisafixedmarkupoveritsmarginalcost(r,w,PE):
Psi=()αs()βs×()1−αs−βs×
(9)
TheoutputpriceisincreasingwiththeenergyconstraintsτEsifacingtherepresentativefirm.Undertheassumptionthattheoutputpriceincreaseswiththelevelofenergyconstraintfacingtherepresentativefirm,thiscouldleadtoageneralizedpriceincreaseintheoutputmarketifasignificantnumberoffirmsfaceenergyconstraintsintheeconomy.Indeed,manyanalysespointoutthatenergyshocksgenerateoutputpricesadjustmentbyproducersintheeconomy(
BarthIIIandRamey
,
2001
;
Bodensteinetal.
,
2011
;
Choi
etal.
,
2017
).
2
Thisiscalledcost-pushinflationoroutputmarketdistortion.Dependingonthestrengthoftheinteractionsbetweenthedifferentsectorsoftheeconomy,adistortionoftheoutputmarketasaresultofenergyconstraintsmayleadtodistortionsofthelabor,capitalandevenenergymarketsagain,thusleadingtoadangerousviciouscircle.
Now,letusrecallourdefinitionoftheTFP.Weoptedfortherevenue-basedTFP(TFPR).Here,theTFPismeasuredbyrevenueproductivityorrevenue-basedproductivitysuchthatTFPRsi=AsiPsi(asin
Hsieh
andKlenow
,
2009
).Fromequation(
9
),wecanthereforeexpresstheTFPRsioffirmiinthesectorsas
TFPRsi=()αs()βs×()1−αs−βs×(1+τEsi)1−αs−βs
follows:
(10)
=()αs()βs×()1−αs−βs×
(11)
Basedonthevaluetakenbytheelasticityofsubstitutionσinmonopolisticcompetition,thefinalexpressionobtainedinequation(
11
)iseithernegative(whenσ<1),positive(whenσ>1),orindefinite(whenσ→1).Therefore,itisnotpossibletodrawhereanyconclusionabouthowenergyshockswillaffecttotalfactorproductivityatthefirm-levelfromatheoreticalperspective(H1).Thatmeansforinstance,theanalysisoftheeffectofpowerconstraintsontheproductivityoffirmsthusremainsanempiricalquestionthatwewill
analyzeinthenextsection
4
.
Furthermore,asthelimτEsi→+∞?convergestowardzero,wecanalsohypothesizethatthegreatertheenergyconstraintsfacingfirms(τEisislarge),themorethereverseeffectsofpowerconstraintsonTFP
aresignificant(H2).Forinstance,thiswouldmeanthatthegreaterthelevelofpowerconstraintsfacedbyafirm,thegreatertheeffectoftheseconstraintsonitsproductivity,andviceversa.
2Forexample,for
Choietal.
(
2017
),a10%increaseininternationaloilpricesraisesinflationby0.4percentagepointsonaverage.
7
Themainpurposeofourfollowingempiricalapproachwillbetotestthesetwomainhypotheses(H1andH2)putforwardthroughthistheoreticalframework.
4Empiricalstrategyanddata
4.1Empiricalstrategy
Oneofthemainchallengesinquantifyingtheeffectofpowersectorconstraintsonfirmperformanceisthatfacingornotpowerconstraintsmightbenon-random(
Alam
,
2013
;
Coleetal.
,
2018
;
Elliottetal.
,
2021
).In-deed,thepowerconstraintsfacedbyfirmsinacountrycanbeexplainedbythemacroeconomic/institutionalphenomenaofthecountryinquestion(lowqualityofregulation,lackoffinancing,politicalinstability,etc.)and/orfirmcharacteristicssuchassize,maturity,qualityofmanagementorevenownership(publicorpri-vate,domesticorforeign).Theserealitiescanalsoexplainthelowlevelofperformanceoffirmsoperatinginthatcountry.Evenwithinthesamecountry,wecanmentiontargetedpublicinvestmentinenergyinfras-tructurenearthebestperformingfirmstosupporttheiroperations,andpublicinvestmentininfrastructure(roadsandrailways)thatcanbothimprovethereliabilityofpowersupply(easeofmaintenanceofpowertransmissionlines)andthetransportationofproductsforfirms.
Todealwiththisidentificationissue,someauthorsinthisliteraturehaveoptedfortheinstrumentalvariablestechniquebasedonvariationsinthepowersupplyfromhydroelectricgenerationasaninstrument(
Fisher-Vandenetal.
,
2015
inChina;
Allcottetal.
,
2016
inIndia;
Coleetal.
,
2018
in14selectedSub-SaharanAfricancountries;
Elliottetal.
,
2021
inVietnam).Meanwhile,webelievethatthisidentificationstrategymightpotentiallyhavethreemajorlimitations:
First,itisnotapplicabletoalargersample,asnotallcountrieshaveanenergymixbasedmainlyonhydropower.Asaresult,studiesusingthisidentificationstrategyfrequentlyfocusonasinglecountry,oronasmallnumberofcountriessimilarintermsofenergymixmainlybasedonhydro-generationoftheelectricity,thusreducingtheexternalvalidity
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