2024年全球甲烷追蹤器

ea

GlobalMethaneTracker

DOCUMENTATION

2024VERSION

Lastupdated:19March2024

INTERNATIONALENERGY

AGENCY

TheIEAexaminesthe

fullspectrum

ofenergyissues

includingoil,gasand

coalsupplyand

demand,renewable

energytechnologies,

electricitymarkets,

energyefficiency,

accesstoenergy,

demandside

managementand

muchmore.Through

itswork,theIEA

advocatespoliciesthat

willenhancethe

reliability,affordability

andsustainabilityof

energyinits

31membercountries,

13association

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UnitedStates

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Contents

GlobalMethaneTracker2024

Documentation

IEA.CCBY4.0.

PAGE|3

Contents

Background 4

Methaneemissionestimates 5

Upstreamanddownstreamoilandgas 5

Incompletecombustionofflares 9

Coalminemethane 10

Emissionsfromfuelcombustion(enduse) 11

Wasteandagriculture 13

Methaneabatementestimates 14

Marginalabatementcostcurvesforoilandgas 14

Well-headpricesusedinnetpresentvaluecalculation 19

Marginalabatementcostcurvesforcoalminemethane 20

Energypricesusedinnetpresentvaluecalculation 24

Projectionsofenergy-relatedmethaneemissionsandassessedtemperaturerises.26

Glossary 28

Oilandgasabatementtechnologies 28

Coalminemethaneabatementtechnologies 30

Policyoptions 33

Policyexplorer 34

References 38

Background

GlobalMethaneTracker2023

Documentation

IEA.CCBY4.0.

PAGE|4

Background

TheIEA’sestimatesofmethaneemissionsareproducedwithintheframeworkoftheIEA’s

GlobalEnergyandClimateModel

(GEC).Since1993,theInternationalEnergyAgency(IEA)hasprovidedmedium-tolong-termenergyprojectionsusingthislarge-scalesimulationmodeldesignedtoreplicatehowenergymarketsfunctionandgeneratedetailedsector-by-sectorandregion-by-regionprojectionsfortheWorldEnergyOutlook(WEO)scenarios.Updatedeveryyear,themodelconsistsofthreemainmodules:finalenergyconsumption(coveringresidential,services,agriculture,industry,transportandnon-energyuse);energytransformationincludingpowergenerationandheat,refineryandothertransformation(suchashydrogenproduction);andenergysupply(oil,naturalgasandcoal).Outputsfromthemodelincludeenergyflowsbyfuel,investmentneedsandcosts,greenhousegasemissionsandend-userprices.

TheGECisaverydata-intensivemodelcoveringthewholeglobalenergysystem.Muchofthedataonenergysupply,transformationanddemand,aswellasenergypricesisobtainedfromtheIEA’sowndatabasesofenergyandeconomicstatistics

(/statistics

)andthroughcollaborationwithotherinstitutions.Forexample,fortheNetZeroby2050:ARoadmapfortheGlobalEnergySectorpublication,resultsfromboththeWEOand

EnergyTechnologyPerspectives

(ETP)

modelshavebeencombinedwiththosefromtheInternationalInstituteforAppliedSystemsAnalysis(IIASA)–inparticulartheGreenhouseGas-AirPollutionInteractionsandSynergies(GAINS)model–toevaluateairpollutantemissionsandresultanthealthimpacts.And,forthefirsttime,resultswerecombinedwiththeIIASA’sGlobalBiosphereManagementModel(GLOBIOM)toprovidedataonlanduseandnetemissionsimpactsofbioenergydemand.TheGECalsodrawsdatafromawiderangeofexternalsourceswhichareindicatedintherelevantsectionsofthe

GECdocumentation.

ThecurrentversionofGECcoversenergydevelopmentsupto2050in29regions.DependingonthespecificmoduleoftheWEM,individualcountriesarealsomodelled:16indemand;113inoilandnaturalgassupply;and32incoalsupply(seeAnnexAoftheGECdocumentation).

Methaneemissionestimates

GlobalMethaneTracker2023

Documentation

IEA.CCBY4.0.

PAGE|5

Methaneemissionestimates

TheGlobalMethaneTrackercoversallsourcesofmethanefromhumanactivity.Fortheenergysector,theseareIEAestimatesformethaneemissionsfromthesupplyoruseoffossilfuels(coal,oilandnaturalgas)andfromtheuseofbioenergy(suchassolidbioenergy,liquidbiofuelsandbiogases).Fornon-energysectors–waste,agricultureandothersources–referencevaluesbasedonpubliclyavailabledatasourcesareprovidedtoenableafullerpictureofmethanesources.

Upstreamanddownstreamoilandgas

Ourapproachtoestimatingmethaneemissionsfromglobaloilandgasoperationsreliesongeneratingcountry-specificandproductiontype-specificemissionintensitiesthatareappliedtoproductionandconsumptiondataonacountry-by-countrybasis.OurstartingpointistogenerateemissionintensitiesforupstreamanddownstreamoilandgasintheUnitedStates(Table1).TheUSGreenhouseGasInventory(USEPA,2023)isusedalongwithawiderangeofotherpublicly-reported,credibledatasources.Thehydrocarbon-,segment-andproduction-specificemissionintensitiesarethenfurthersegregatedintofugitive,ventedandincompleteflaringemissionstogiveatotalof19separateemissionintensities.

Table1.CategoriesofemissionsourcesandemissionsintensitiesintheUnited

States

Hydrocarbon

SegmentProductiontypeEmissionstype

Intensity

(massmethane/massoilorgas)

Oil

UpstreamOnshoreconventionalVented

0.36%

Oil

UpstreamOnshoreconventionalFugitive

0.09%

Oil

UpstreamOffshoreVented

0.36%

Oil

UpstreamOffshoreFugitive

0.09%

Oil

UpstreamUnconventionaloilVented

0.72%

Oil

UpstreamUnconventionaloilFugitive

0.18%

Oil

DownstreamVented

0.004%

Oil

DownstreamFugitive

0.001%

Oil

OnshoreconventionalIncomplete-flare

0.06%

Oil

OffshoreIncomplete-flare

0.01%

Oil

UnconventionalIncomplete-flare

0.04%

Naturalgas

UpstreamOnshoreconventionalVented

0.29%

Naturalgas

UpstreamOnshoreconventionalFugitive

0.11%

Naturalgas

UpstreamOffshoreVented

0.29%

IEA.CCBY

PAGE|6

4.0.

Hydrocarbon

Segment

Productiontype

Emissionstype

Intensity

(massmethane/massoilorgas)

Naturalgas

Upstream

Offshore

Fugitive

0.11%

NaturalgasUpstreamUnconventionalgasVented0.43%

Naturalgas

UpstreamUnconventionalgas

Fugitive

0.17%

Naturalgas

Downstream

Vented

0.15%

Naturalgas

Downstream

Fugitive

0.10%

TheUSemissionsintensitiesarescaledtoprovideemissionintensitiesinallothercountries.Thisscalingisbaseduponarangeofauxiliarycountry-specificdata.Fortheupstreamemissionintensities,thescalingisbasedontheageofinfrastructure,typesofoperatorwithineachcountry(namelyinternationaloilcompanies,independentcompaniesornationaloilcompanies)andaverageflaringintensity(flaringvolumesdividedbyoilproductionvolumes).Fordownstreamemissionintensities,country-specificscalingfactorswerebasedupontheextentofoilandgaspipelinenetworksandoilrefiningcapacityandutilisation.

Figure1

Methodologicalapproachforestimatingmethaneemissionsfromoilandgasoperations

IEA.CCBY4.0.

Thestrengthofregulationandoversight,incorporatinggovernmenteffectiveness,regulatoryqualityandtheruleoflawasgivenbytheWorldwideGovernanceIndicatorscompiledbytheWorldBank(2023),affectsthescalingofallintensities.Someadjustmentsweremadetothescalingfactorsinalimitednumberofcountriestotakeintoaccountotherdatathatweremadeavailable(wherethiswasconsideredtobesufficientlyrobust),suchascomprehensivemeasurementstudies.Thisincludesdataonsatellite-detectedlargeemittersand“basin-levelinversions”,whichusesatellitereadingstoassessmethaneemissionsacrossawideroilandgasproductionregion,basedondataprocessingby

IEA.CCBY4.0.

PAGE|7

Kayrros,anearthobservationfirm(seeBox1.6).Italsoincludesspecificpolicyeffortstocontrolmethaneemissionsfromtheoilandgassectors,astrackedinthe

IEAPoliciesDatabase.

Table2providestheresultantscalingfactorsinthetopoilandgasproducers(thecountrieslistedcover90%ofglobaloilandgasproduction).ThesescalingfactorsaredirectlyusedtomodifytheemissionsintensitiesinTable1.Forexample,theventedemissionintensityofonshoreconventionalgasproductionintheRussianFederation(hereafter“Russia”)istakenas0.29%×1.7=0.49%.Theseintensitiesarefinallyappliedtotheproduction(forupstreamemissions)orconsumption(fordownstreamemissions)ofoilandgaswithineachcountry.

Table2.ScalingfactorsappliedtoemissionintensitiesintheUnitedStates

Country

Oil&gas

production

in2023

OilGas

mtoeUpstreamDownstreamUpstream

Downstream

UnitedStates

17241.01.01.0

1.0

Russia

10782.31.31.7

1.1

SaudiArabia

6430.80.40.6

0.4

Canada

4521.00.51.0

0.5

Iran

4253.10.91.4

0.9

China

4091.50.91.1

0.8

UnitedArabEmirates

2491.40.71.2

0.6

Iraq

2311.40.50.8

0.5

Qatar

2271.10.61.0

0.6

Norway

2010.00.00.0

0.0

Brazil

1961.71.31.7

1.3

Kuwait

1631.40.71.1

0.7

Algeria

1584.71.42.1

1.4

Australia

1520.80.50.6

0.5

Mexico

1331.60.91.1

0.8

Kazakhstan

1162.81.42.5

1.4

Nigeria

1063.81.82.4

1.8

Oman

911.60.71.0

0.7

Malaysia

902.21.11.5

1.1

Indonesia

853.21.52.1

1.5

Egypt

852.41.01.3

1.0

Turkmenistan

7715.84.56.6

4.5

Argentina

752.51.11.8

1.1

Libya

723.71.01.7

1.0

India

673.21.62.1

1.5

Methaneemissionestimates

GlobalMethaneTracker2023

Documentation

IEA.CCBY4.0.

PAGE|8

Box1Integratingemissionsestimatesfromsatellites

TheGlobalMethaneTrackerintegratesresultsfromallpublicly-reported,crediblesourceswheredatahasbecomeavailable.Thisincludesemissionsdetectedbysatellites.Changesintheatmosphericconcentrationofmethanecanbeusedtoestimatetherateofemissionsfromasourcethatwouldhavecausedsuchachange.Thisisdonebasedondataprocessingby

Kayrros,

anearthobservationfirm,toconvertreadingsofconcentrationstoidentifylargesourcesofemissionsfromoilandgasoperations.Reportedemissionsencompassmethanesourcesabove5tonnesperhour.

OilandgasemissionsdetectedbysatellitesarereportedasaseparateitemwithintheMethaneTracker.Theseestimatesarebasedonaconservativescalingupofemissioneventsdirectlydetectedtotakeintoaccounttheperiodwithintheyearwhenobservationscouldbemade.Thisiscarriedoutforallregionswhereobservationswerepossibleforatleast20daysintheyear.

Theincreasingamountofdataandinformationfromsatelliteswillcontinuetoimproveglobalunderstandingofmethaneemissionslevelsandtheopportunitiestoreducethem.However,satellitesdohavesomelimitations:

.Existingsatellitesstruggletoprovidemeasurementsoverequatorialregions,northernareas,mountainranges,snowyorice-coveredregionsorforoffshoreoperations.Thismeansthattherearealargenumberofmajorproductionareaswhereemissionscannotbeobserved.

.Existingsatellitesshouldbeabletoprovidemethanereadingsgloballyonadailybasisbutthisisnotalwayspossiblebecauseofcloudcoverandotherweatherconditions.During2023therewerearound70countrieswheremethaneemissionsfromoilandgasoperationscouldbedetectedforatleast20days.Largeemissioneventswereobservedin20ofthesecountriesin2023.CoveragetendstobebestintheMiddleEast,AustraliaandpartofCentralAsia,whereadirectmeasurementcouldbemadeevery3-5days.Ontheremainingdays,cloudcoverageorotherinterferencepreventedmeasurementoperations.

.Theprocessofusingchangesintheatmosphericconcentrationofmethanetoestimateemissionsfromaparticularsourcecanrelyonalargelevelofauxiliarydataandbesubjecttoahighdegreeofuncertainty.

ThesatellitereadingsincludedintheGlobalMethaneTrackercurrentlyprovidedataonlyforlargeemittingsources.Thisis,ofcourse,subjecttoahighdegreeofuncertainty,butensuresthatcountry-by-countyestimatesprovideacomprehensivepictureofallmethaneemissionssources.Asadditionaldatabecomesavailablefrommeasurementcampaigns–whetherrecordedfromgroundoraerialprocessesorbysatellites–thesewillbeincorporatedintotheGlobalMethaneTrackerandestimatesadjustedaccordingly.

IEA.CCBY4.0.

PAGE|9

Incompletecombustionofflares

Ourapproachtoestimatingmethaneemissionsfromflaringreliesongeneratingcountry-specificandproductiontype-specificcombustionefficienciesthatareappliedtoflaringdataonacountry-by-countrybasis.GlobalestimatesofflaredvolumesofnaturalgasarebasedonreporteddatafromtheWorldBank’sGlobalGasFlaringReductionPartnership.ThesedataaretakenfromtheNationalOceanicandAtmosphericAdministration(NOAA)andthePayneInstitute(WorldBank,2023).

Combustionefficienciescanreduceasaresultoflowerproductionrates,highandvariablewinds,andpoormaintenanceresultingfromlackofregulatorypolicy,enforcementorcompanypolicy(Johnson,2001;Kostiuk,2004).Weestimatecombustionbaseduponarangeofauxiliarycountry-specificdata:

.Oilproductiontype(unconventionalonshore,conventionalonshoreandoffshore),companytypeandproductionstart-upyear,basedonRystadEnergyUCubedata.CompanytypeisgroupedinMajors(ExxonMobil,Chevron,BP,RoyalDutchShell,EniSpA,TotalEnergies,andConocoPhillips),NationalOilCompanies(NOCs)andOther(e.g.Independent,PrivateEquity).MaintenancelevelstoimproveflaringcombustionefficiencieswereappliedseparatelybycompanytypeassumingthatmorescrutinyfrominvestorsandthepublicisplacedontheMajorsascomparedtoNOCsorOther.

.FlaringdesignstandardsAPI521andAPI537wereconsideredgaugeflarestacksizes,assumingbest-casedesignandoptimalflareparametersduringearlyproductiontime(API,2014;API,2017).

.TheimpactofwindspeedwasincorporatedusingNASA’sPredictionofWorldwideEnergyResources(POWER)MeteorologyDataAccessViewer(NASA,2021).Onshorewindspeedswereassessedat10mandoffshorewindspeedsat50mtoreflectclosestheightofflarestacksinactualfacilitydesign.Windspeedvariabilityanditsimpactoncombustionefficiencywasincorporatedcorrespondingtothelocationofproduction.

.TheWorldBank’sWorldwideGovernanceIndicatorsdatabase(2023)wasusedasthebasistoassessthegeneralstrengthofregulatoryoversight.

Adjustmentsaremadetoconsiderdataonsatellite-detectedlargeemittersandspecificpolicyeffortstocontrolmethaneemissionsfromtheoilandgassectors,astrackedintheIEAPoliciesDatabase.Countrieswithstrongerflaringregulationandstrongregulatoryoversightarecalibratedassumingcompaniesweremandatedtoquicklyinspectandrepairanymalfunctioningorpoorperformingflaresites.Countrieswithweakflaringregulationandlowlevelsofoversightareassumedtoperformlittletonoadditionalmaintenance.

IEA.CCBY4.0.

PAGE|10

Coalminemethane

TheIEA’sestimatesofcoalminemethane(CMM)emissionsarederivedfrommine-specificorregion-specificemissionsintensitiesforAustralia,thePeople’sRepublicofChina(hereafter“China”),IndiaandtheUnitedStates(whichcollectivelyaccountedforaround75%ofglobalcoalproductionin2022).EmissionintensitiesforcoalminesintheUnitedStatesarebasedonthelatestUSEnvironmentalProtectionAgency’s

GreenhouseGasReportingProgramand

USGreenhouseGasInventory.

EmissionintensitiesforcoalproductioninAustraliaarebasedonitslatest

NationalInventoryReports.

ThisissupplementedbydatasourcesthatprovideddisaggregatedCMMdataforChina

(Wangetal.,

2018;

Zhuetal.,2017

)andIndia

(SinghA.K.andSahuJ.N.,2018)

(IndiaMinistry

ofCoal,2018)

.

Themine-levelCMMestimatesgeneratedinthiswayareaggregated,verifiedandcalibratedagainstcountry-levelestimatestakenfromsatellitesandatmosphericreadings(e.g.

Shenetal.,2023;

Dengetal.,2022;

Milleretal.,2019

).Methaneemissionsarecalculatedseparatelyforthethreemaincoaltypesinthe

Global

EnergyandClimateModel

:steamcoal;cokingcoal;andlignite(see

Table3

forasummaryofintensities).Methaneemissionsfrompeatminingarelikelytoberelativelysmallandarenotincludedinthisanalysis.

Basedonthesedata,coalquality,minedepth,andregulatoryoversightareusedtoestimateCMMemissionintensitiesforminesinothercountriesforwhichtherearenoreliablemeasurement-basedestimates.TheWorldBank’sWorldwideGovernanceIndicatorsdatabase(2023)wasusedasthebasistoassessthegeneralstrengthofregulatoryoversightalongsidepoliciesrelatedtocoalminemethanetrackedintheIEA’s

PoliciesDatabase.

Theemissionsintensitiesalsoconsiderestimatesfromsatellite-detectedlargeemittersandbasin-levelemissionsforcoalproducingregions,basedondataprocessingby

Kayrros.

Thedepthandtype(surfaceorunderground)ofindividualminesinoperationaroundtheworld,aswellastheassociatedcoalresource(thermalormetallurgical)andmethanegascontent,isbasedonthe

GEMGlobalCoalMine

Tracker

andthe

CRUdatabase

.Deepercoalseamstendtocontainmoremethanethanshallowerseams,whilecoalofhigherrank(e.g.anthracite)hashighermethanecontentthancoaloflowerrank(e.g.lignite).Intheabsenceofanymitigationmeasures,methaneemissionstotheatmospherewillthereforetendtobehigherforundergroundminesthanforsurfacemines.Minesthathavebothsurfaceandundergroundoperationsareclassifiedasunderground.Minesthatproduceboththermalormetallurgicalcoalareclassifiedonacountry-by-countryleveltomatchIEAcountry-leveldataoncoalproduction.

Methaneemissionestimates

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Table3.Emissionsintensitiesofmajorcoalproducers(kgCH4/tonneofcoalequivalent)

Region

Steamcoal

Cokingcoal

Lignite

Australia

3.7

5.6

0.4

China

5.0

10.3

-

India

4.3

12.8

0.4

Indonesia

3.1

6.2

-

Russia

8.8

18.0

0.9

SouthAfrica

8.1

15.7

-

UnitedStates

3.2

14.2

0.3

Note:Cokingcoalisthesameasmetallurgicalcoal.Intensitiesreflectaverageminecharacteristicsineachregion(minedepth,coalquality,regulatoryoversight,includingavailableprovinceorstate-levelinformation).

ResultingestimatesofglobalCMMemissionsamounttojustunder40Mt(for2023),withintherangeof

othermodelling

efforts.Methaneintensitiesforcokingcoalaregenerallyhigherbecauseproductioncomesfromdeepermineswithcoaldepositsofhigherrank.DifferencesbetweeninputsourcesandIEAestimatescanresultfromauxiliarydata(e.g.satellite-basedmeasurements)oractivitydata.Forexample,theIEAestimateforAustralianCMMemissionsisabout1.7Mt(for2023),abovetheofficialsubmissiontotheUnitedNationsFrameworkConventiononClimateChange(UNFCCC)of1.0Mt(for2020),thisdifferenceismostlydrivenbyauxiliarydata,includingdatafromstudiesindicatinghigherfossilemissionsbasedon

satelliteinversions.

Intensitiesvarysignificantlyaccordingtominecharacteristicswithineachcountry(e.g.Australia’scokingcoalmethaneintensityisestimatedtoberelativelysmallasmostofitsproductioncomesfromlow-depthmineswithlowermethanecontent).

Emissionsfromabandonedminesarenotincludedinourestimatesasrelatedmeasurementstudiescoveralimitednumberoffacilitiesandregions.Likewise,thereislimiteddataavailableonclosedmines(e.g.yearofclosure,conditionofthemine,areacovered).Thesesourcescouldrepresentanimportantsharesofoverallmethaneemissionsfromcoaloperations.Forexample,theUnitedStates

EnvironmentalProtectionAgency

indicatesthatabandonedminesareresponsibleformorethan10%ofCMMintheUnitedStates.Referencesandsuggestionsregardingthistopicarewelcomeasthiscouldbeanareaoffuturedevelopment.

Emissionsfromfuelcombustion(enduse)

Methaneemissionsareassociatedwithfueluse,eitherduetoincompletecombustionorasfugitiveemissions.Methanecanleakfromstoragevessels,pipelinesorenduseappliances(e.g.stovetops).Itcanalsoescapewithoutcombustionfrommobileapplications(e.g.naturalgasfuelledvehicles)orstationaryapplications(e.g.powergenerators).

Methaneemissionestimates

GlobalMethaneTracker2023

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IEA.CCBY4.0.

PAGE|12

Weestimatethataround10Mtofmethaneemissionscomesduringtheincompletecombustionoftraditionaluseofbiomassforcookingorheatinginemergingmarketanddevelopingeconomies.Withregardstofossilfuels,weestimatethatabout3Mt(2%ofenergy-relatedmethaneemissions)comesfromtheenduseofcoal,oilproductsandnaturalgas.ThisestimateisbasedontheemissionsfactorspublishedbytheIntergovernmentalPanelonClimateChange(IPCC)forenergyconsumptioninhomes,industriesandinthetransportsector.

EstimatesformethaneemissionsfromtheuseoffuelsinstationaryandmobileapplicationsarefromtheIEA

GreenhouseGasEmissionsfromEnergy

forthelatestyearavailableforeachregion.TheTier1methodologyfromthe2006IPCCGuidelinesforGHGinventorieshavebeenadoptedforthepurposeofestimatingthenon-CO2emissionsfromfuelcombustion.UnlikeCO2,thenon-CO2greenhousegasemissionsfromfuelcombustionarestronglydependentonthetechnologyused.Sincethesetoftechnologies,appliedineachsectorvaryconsiderably,theguidelinesdonotprovidedefaultemissionfactorsforthesegasesonthebasisoffuelsonly.Sector-specificTier1defaultemissionfactorscanprovideareasonableestimatefortheseemissions.

Somemeasurementcampaignshavesuggestedthattheseemissionsfactorscouldsignificantlyunderestimateactualemissionsacrossdifferentend-useenvironments,includinginindustries(Zhouetal.,2019),cities(Sargentetal.,2021)andhouseholds(Lebeletal.,2022).Emissionlevelsmightalsohavechangedinrecentyears.Theseareareaswithveryhighlevelsofuncertaintyandourestimateswillcontinuetobeupdatedastheevidencebasegrows.

Forestimatingtheemissionscorrespondingtostationarycombustion,thedefaultTier1non-CO2emissionfactorsprovidedinthe2006IPCCguidelinesassumeeffectivecombustioninhightemperature.TheemissionfactorsprovidedforCH4arebasedonthe1996IPCCGuidelinesandhavebeenestablishedbyalargegroupofinventoryexperts.However,duetotheabsenceofsufficientmeasurementsandsincetheconceptofconservationofcarbondoesnotapplyinthecaseofnon-CO2gases,theuncertaintyrangeassociatedwiththeseestimatesaresetatafactorofthree.

Similarlyformobilecombustion,thenon-CO2emissionfactorsaremoredifficulttoestimateaccuratelythanthoseforCO2,astheywilldependonvehicletechnology,fuelandoperatingcharacteristics,mainlythecombustionandemissioncontrolsystemofthevehicles.Thus,defaultfuel-basedemissionfactorsarehighlyuncertain.However,theTier1methoddoesallowusingfuel-basedemissionfactorsifitisnotpossibletoestimatefuelconsumptionbyvehicletype.

Formoredetailsontheunderlyingmethodologyandassumptionspleaserefertothe

IEAGHGemis