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1、SAF85 Technical Brief Aviation SectorW H I T E P A P E RA U G U S T 2 0 2 4In collaboration with Boston Consulting GroupContentsImages:Getty Images 2024 World Economic Forum.All rights reserved.No part of this publication may be reproduced or transmitted in any form or by any means,including photoco

2、pying and recording,or by any information storage and retrieval system.Disclaimer This document is published by the World Economic Forum as a contribution to a project,insight area or interaction.The findings,interpretations and conclusions expressed herein are a result of a collaborative process fa

3、cilitated and endorsed by the World Economic Forum but whose results do not necessarily represent the views of the World Economic Forum,nor the entirety of its Members,Partners or other stakeholders.1 Introduction1.1 Purpose2 SAF85 overview2.1 Understanding the First Movers Coalition aviation sector

4、 commitment2.2 Review of SAF pathways potential to meet FMC threshold3 Deep dive:Power-to-liquids(PtL)3.1 Technology overview3.2 Greenhouse gas emissions from power-to-liquid SAF pathways3.3 Additionality of renewable electricity for power-to-liquids fuels4 Deep dive:Gasification Fischer-Tropsch(bio

5、mass-to-liquids)5 Additional analyses5.1 Impact of carbon capture on SAF pathways5.2 Impact of induced land-use change on SAF emissions calculations5.3 Comparison of CORSIA to other standards and emissions methodologies5.4 Novel SAF pathways not specified in this document5.5 Miscanthus and other fee

6、dstocksContributorsEndnotes33446881011121414151719192021SAF85 Technical Brief:Aviation Sector2Introduction1This document provides guidance on what constitutes SAF85 to FMC members looking to fulfil their aviation commitment.Launched in 2021 by US Special Presidential Envoy for Climate John Kerry and

7、 the World Economic Forum,the First Movers Coalition(FMC)is the leading global public-private partnership to scale emerging climate technologies to decarbonize heavy-emitting industrial sectors,including aviation.FMC aviation sector members have made the ambitious commitment to procure sustainable a

8、viation fuel that has at least 85%lower greenhouse gas emissions than conventional jet fuel SAF85 by 2030.While many FMC aviation members have already managed to secure SAF85,the number and complexity of SAF production pathways and feedstocks on the horizon,as well as significant project-level nuanc

9、es,make it difficult to identify products that meet FMCs high threshold.Each project,pathway,or feedstock can result in significant variations in carbon intensity,which can create confusion and deter action.FMC members have expressed the need for“rules of thumb”and key questions to ask suppliers to

10、identify SAF that meets the FMC threshold.Building on the 2023 FMC Sustainable Aviation Fuels Offtake Manual,this document aims to empower FMC members and companies along the fuel value chain and beyond as they look to purchase SAF85 by helping:SAF buyers understand the typical carbon intensity of d

11、ifferent pathways,criteria to assess a projects potential to meet the FMC threshold and key questions to ask suppliers.SAF producers understand the requirements of FMC members,who represent one of the largest demand signals for sustainable aviation fuel in the world.The broader SAF ecosystem(e.g.air

12、ports,regulators,enabling technology developers)assess where the market is moving and which SAF pathways will be of high interest to ambitious movers over the next 5-10 years.The document provides guidance on SAF pathways likely to meet the FMC commitment threshold,including rules-of-thumb for asses

13、sing SAF projects,based on the latest literature and input from FMC member organizations.However,it does not override the current FMC aviation commitment or serve as a peer-reviewed document.Such guidance is intended to accelerate the procurement of SAF85 by FMC members and other ambitious corporate

14、s.Purpose1.1SAF85 Technical Brief:Aviation Sector3SAF85 overview2Several rules-of-thumb can help members navigate the variety of SAF production pathways and feedstocks to identify supply that meets FMC commitments.In the FMC aviation sector,members are classified as either airlines/airfreights(i.e.f

15、uel purchasers)or airfare/airfreight purchasers and have made commitments as follows in Figure 1.The commitment specifies that the carbon emissions calculation methodology underpinned by CORSIA,the Carbon Offsetting and Reduction Scheme for International Aviation,is the default system through which

16、members should measure carbon emissions.This is because CORSIA has been fully adopted by the International Civil Aviation Organization(ICAO)as the scheme for reducing GHG emissions in international aviation.1 Furthermore,the EU ETS,2 US 40B SAF tax credit3 and Civil Aviation Authority of Singapore(C

17、AAS)4 have adopted CORSIA as a key GHG emissions measurement scheme.However,the commitment language specifies that“similar frameworks”can also be used.For example,in addition to CORSIA,the US 40B SAF tax credit also accepts a new version of the GHGs,Regulation Emissions and Energy Use in Transportat

18、ion(GREET)model,5 which was released in April 2024;however,it only applies to a select few SAF pathways(a comparison of similar frameworks is discussed in detail in section 5.3).Understanding the First Movers Coalition aviation sector commitment2.1First Movers Coalition aviation sector commitment la

19、nguageFIGURE 11.FMC will use default values OR actual lifecycle analysis(LCA)using an eligible Sustainability Certification Scheme from CORSIA(or similar frameworks).2.FMC intends to evaluate and potentially adopt PtL guidance for CO2 and H2 sources from CORSIA(or similar frameworks)once they are re

20、leased.By 2030,we will replace at least 5%of conventional jet fuel demand with sustainable aviation fuels(SAFs)that reduce life-cycle GHG emissions by 85%or more when compared with conventional jet fuel,1,2 and/or zerocarbon emitting propulsion technologies.Airline/air freight Airfare/air freight pu

21、rchaserBy 2030,we will partner with air transport operators to replace at least 5%of conventional jet fuel used for our air travel/freight with sustainable aviation fuels(SAFs)that reduce life-cycle GHG emissions by 85%or more when compared with conventional jet fuel,1,2 and/or zero-carbon emitting

22、propulsion technologies.SAF85 Technical Brief:Aviation Sector4According to the 2024 CORSIA Handbook,6 the default baseline for fossil jet fuel is 89 grams of CO2 equivalent per megajoule(gCO2e/MJ),which means that for SAF to meet the FMC 85%life-cycle emissions reduction commitment threshold,it must

23、 have a life-cycle carbon intensity at or lower than 13.35 gCO2e/MJ,following CORSIA.CORSIA default lifecycle carbon intensity of sustainable aviation fuels(gCO2e/MJ)FIGURE 2Induced land use change(ILUC)emissionsProcess emissions1.Negative ILUC values due to the high soil carbon sequestration and bi

24、omass carbon from producing cellulosic crops.2.CORSIA also includes default values for HEFA co-processed at petroleum refineries,which is not included here because values are comparable or higherthan their HEFA counterparts listed.FMC threshold:13.35 gCO2e/MJra l po Pssarghct iw Swo l l i WEucalyptu

25、sseud i ser t sero Frevot s nro Cwar t s taeh W)GBN%0(WS Msuhtnacs i Ml i o ml a Pl i o deesepa Rl i o yo Sl i o an i l ema Cwo l l a Tahpor ta Jl i o atan i ra CPFAD2l i o nro Cl i o gn i kooc des Uenacragu Steebragu Sn i arg nro Cssarghct iw Ssessa l o Menacragu Srevot s nro Cseud i ser t sero Fsu

26、htnacs i Mn i arg nro Cssarghct iw Senacragu Sseud i ser g Aseud i ser t sero Fsuhtnacs i Msag et sa Ws3d i uq i l-ot-rewo P9 81 26 12 12 18 8 8 5 2 -7 73 76 69 23 22 22 21 27 1l eu f te j l i sso F4 44 46 89 46 33 39 24 24 110 14 33 35 25 29 9 201-50 2Gasification Fischer-Tropsch(biomass-to-liquid)

27、Hydro-processed esters&fatty acids(HEFA)Isobutanol alcohol-to-jet(AtJ)Ethanol alcohol-to-jet(AtJ)Microbiologic conversionSynthesized iso-paraffins(SIP)3.German Environment Agency(Umwelt Bundesamt).1SAF85 Technical Brief:Aviation Sector5Figure 2 compares the 30+SAF pathways that CORSIA has published

28、default carbon intensity values for.7 Default values are a set of reference values that can be used by airlines for calculating the emissions of SAF in lieu of available project-specific values.It should be noted very clearly that a valid project-level life-cycle analysis using CORSIA or a similar f

29、ramework always takes precedence over these default values.For power-to-liquids(PtL),where CORSIA has not published a specific default carbon intensity value,the value is sourced from the German Environment Agency(Umwelt Bundesamt),which has published one of the most comprehensive power-to-liquids s

30、tudies to date.8There are few pathways where the default CORSIA value meets the threshold for SAF85,primarily concentrated in the Gasification Fischer-Tropsch(GFT,also called biomass-to-liquids or BtL).The German Environment Agency emissions intensity figure for power-to-liquids(PtL)technologies als

31、o meets the threshold for SAF85.The default values for the four other specified pathways hydroprocessed esters and fatty acids(HEFA),ethanol and isobutanol alcohol-to-jet(AtJ),synthesized isoparaffins(SIP)and microbiologic conversion do not meet the FMC SAF85 threshold,with the exception of ethanol

32、AtJ using miscanthus as feedstock(miscanthus is discussed in detail in Section 5.4).However,SAF emissions vary widely from project to project,and due to variations in feedstock cultivation,transport and logistics,land-use change and the addition of technologies like carbon capture,other pathways cou

33、ld still meet the SAF85 threshold(these sensitivities are discussed in detail in section 5.1 and 5.2).For example,while used cooking oil(UCO)HEFA has a CORSIA default life-cycle value of 14 gCO2e/MJ,which is just outside of the FMC threshold,in practice,certain UCO HEFA projects may reduce emissions

34、 by greater than 85%.The IEA Bioenergy report“Comparison of Biofuel Life Cycle Analysis Tools:FAME and HVO/HEFA”cites four different models of cradle-to-pump emissions from UCO HEFA reaching the FMC threshold.9 Despite the CORSIA default value for UCO HEFA suggesting an 85%life-cycle emissions reduc

35、tion may not be possible,the pathway still has some potential to meet the FMC threshold and thus a project-level LCA should be conducted to determine if it meets the threshold.Therefore,CORSIA default values should be considered a helpful reference point and only be used in the absence of a project-

36、specific life-cycle analysis(LCA)that is conducted using the CORSIA methodology or similar frameworks.This document also presents a snapshot in time.As technology improves and evolves,the potential for feedstocks or pathways to meet the FMC threshold may change and expand.The rest of this document w

37、ill explore in more depth how members can think about the potential of each pathway to meet the FMC threshold,including a dedicated section on GFT and PtL,as well as a sensitivities analysis on the potential for additional low-carbon strategies to get the remaining pathways within the commitment thr

38、eshold.It is important to note that FMC is explicitly technology-agnostic in its aviation commitment as long as the fuel in question meets the emissions reduction criteria of the commitment.With this in mind,Figure 3 summarizes the“rule of thumb”conclusions members can reference when assessing offta

39、ke for an SAF project.While the following sections provide guidance on which SAF production pathway is likely to meet the 85%carbon emissions reduction threshold set by FMC,when exploring offtakes,FMC Aviation members should keep in mind other non-carbon criteria that could still impact the overall

40、sustainability of the fuel,for example,competition with food(beyond the impact this will have on carbon stock,captured by land use change figures),water resources,soil and social development.CORSIA and equivalent methodologies underpin a list of criteria that fuels will need to meet to be considered

41、 sustainable.10Review of SAF pathways potential to meet FMC threshold2.2SAF85 Technical Brief:Aviation Sector6Summary of project-level guidance on the potential of SAF pathways to meet the FMC commitment thresholdFIGURE 3What SAF pathway?Power-to-liquidsGasification Fischer-Tropsch(Biomass-to-liquid

42、)HEFA,SIP,non-PtLalcohol-to-jet,otherWhat technology pathway is used?Fischer-Tropsch E-methanol Alcohol-to-JetNot yet ASTM/CORSIA approvedLikelihood to meet FMC thresholdWhat type of feedstock is used?2nd generation(wastes,residues)1st generation(primary crops)Are CCUS or other low-carbon strategies

43、 or feedstocks(e.g.UCO)used?YesNoHydrogen(H2)is green or pink(i.e.,nuclear)CO2 sourced from direct-air capture(DAC)or point-source captureElectricity(for DAC and H2)is carbon neutralAssume high potential if:Conduct project-level LCA using CORSIA or similar framework to confirmConduct project-level L

44、CA using CORSIA or similar framework to confirmFeedstock is 95%biogenicNo/negative land-use changeAssume high potential to meet FMC threshold if:Conduct project-level life-cycle analysis(LCA)using CORSIA or similar framework to confirmSAF85 Technical Brief:Aviation Sector7Deep dive:Power-to-liquids3

45、There is high interest in PtL because of its high carbon abatement potential,and thus likelihood to meet the FMC commitment.Power-to-liquids(PtL)pathways,both Fischer-Tropsch PtL and e-methanol alcohol-to-jet(AtJ)PtL have a very high potential to meet the FMC threshold as long as they use green H2,c

46、lean CO2,and renewable electricity.While the e-methanol AtJ pathway is currently not an ASTM-approved conversion process,it is expected to be approved by 2030.Key questions to ask PtL SAF suppliers:How is hydrogen being produced(e.g.gray,blue,green,pink)and from where is it being sourced(e.g.co-loca

47、ted facility,within same region/country,imported)?Where is the CO2 being sourced from(technology and geography)?Where is the electricity being sourced for DAC and fuel conversion(geography and power generation technology)?Following CORSIA or a similar methodology,is the final life-cycle carbon inten

48、sity at or below 13.35 gCO2e/MJ?For Fischer Tropsch,does the final product comply with ASTM D7566?Power-to-liquids(PtL)fuels,also known as synthetic fuels,e-fuels,or renewable fuels of non-biological origin(RFNBOs),are produced with electricity as the primary energy source.As feedstock,they take hyd

49、rogen(H2)from water and carbon dioxide(CO2)from either the air(via direct air capture)or an industrial waste gas stream(via point-source carbon capture).11 H2 and CO2 are combined to create a sustainable aviation fuel via two potential PtL pathways:Fischer-Tropsch PtL:The Fischer-Tropsch pathway is

50、the same as the second stage of the biomass-to-liquids conversion process,but uses a different feedstock.Rather than gasifying biomass feedstock,PtL Fischer-Tropsch takes a synthesis gas formed from a combined H2 and CO2 stream and forms it into a crude renewable hydrocarbon chain,which can then be

51、upgraded to e-kerosene via hydrocracking,isomerization and distillation.AtJ PtL:Alternatively,e-methanol(methanol formed synthetically through the combination of H2 and CO2)can be upgraded to e-kerosene via the alcohol-to-jet process(olefin synthesis,oligomerization and hydrotreatment).This process

52、is similar to ethanol and isobutanol alcohol to-jet technologies,but uses e-methanol as a feedstock rather than biomass.ASTM approval.For a SAF to be legal and safe to blend into jet fuel at airports,its thermo-chemical properties must comply with fuel specifications issued by ASTM International in

53、the US an internationally adopted standards organization for many materials or by equivalent country-specific standards(e.g.Def-Stan 91-091 in the United Kingdom).These properties are specified in ASTM D7566,12 which includes the technology used to produce the SAF and the maximum volumes it can be b

54、lended into jet fuel mix to produce safe drop-in jet fuel.Fischer-Tropsch PtL is approved via the FT-SPK pathway,currently approved for up to 50%blends with conventional jet fuel.However,while AtJ via ethanol and isobutanol are approved,AtJ via e-methanol has yet to be approved and given a blend rat

55、io from ASTM.However,ICAO has indicated that this pathway is under evaluation by ASTM13 and there are multiple e-methanol PtL plants planned to be operational before 2030,14 indicating some confidence that this may change in the coming years.Technology overview3.1EXECUTIVE SUMMARYSAF85 Technical Bri

56、ef:Aviation Sector8Diagram of power-to-liquids technical production pathwaysFIGURE 41.Hydrocracking,isomerization and distillation.2.Alcohol-to-jet process:Olefin synthesis,oligomerization and hydrotreatment.Source:Adapted from Umwelt Bundesamt(German Environment Agency),Power-to-Liquids Report,Jan

57、2022.3PtL SAF production via Fischer-Tropsch processASTM-approved pathway(ASTM D7566)specified at a 50%blend ratioCO2 captureElectrolysisFischer-Tropsch synthesisUpgrading1Transport&distributionReverse water gas shiftCO2CO2/airHeatHeatPtlCxHyCrude PtlH2H2COElectricityWater2143PtL SAF production via

58、e-methanol alcohol to jet processCO2 captureElectrolysisMethanol synthesisConversion&upgrading2Transport&distributionCO2CO2/airHeatHeatPtlMeOHH2ElectricityWater214Not yet an ASTM-approved pathwayCORSIA has not released default life-cycle carbon intensity values for either PtL pathway.However,in part

59、 1 of their report“CORSIA Eligible Fuels:Life Cycle Assessment Methodology”released in June 2022,ICAO lays out the process for adding default values,which requires sufficient scale and data to conduct a reliable LCA.15In lieu of this,we reference a comprehensive report on PtL,which was published in

60、January 2022 by Umwelt Bundesamt(the German Environment Agency).16 The report estimates the life-cycle carbon intensity of PtL SAF to be between 5-10 gCO2e/MJ,falling well within the FMC commitment threshold.While the majority of emissions are coming from the heat and electricity required for these

61、processes,emissions in PtL pathways come from four stages throughout the fuel production process(see Figure 4):1.Hydrogen production(electrolysis).When the H2 produced is green,this stage accounts for 50-55%of total emissions,which primarily depends on the carbon footprint of the electricity used.No

62、te:If the project in question is using H2 that is not green,this will definitely increase the life-cycle emissions.If the project uses gray H2(hydrogen produced from steam-reforming natural gas),it is unlikely to meet the FMC emissions threshold,and if it uses blue H2(gray H2 with carbon capture)its

63、 carbon intensity likely depends on the capture rate of blue H2 and a project-specific LCA should be conducted to determine the carbon intensity of the SAF.Pink H2(i.e.H2 produced using nuclear power)should be treated similarly to green H2 because it still uses the water electrolysis process and the

64、 energy source has a low carbon footprint.17 While no SAF PtL projects announced to date have specified plans to use non-green H2 as a feedstock,18 attractiveness of blue H2 due to economics and policy incentives(e.g.potentially restrictive standards on green H2 for the United States 45V tax credit1

65、9)may increase the likelihood of this in the future.2.CO2 supply(capture).This accounts for 30-35%of total emissions,primarily from electricity.Note:CO2 can be sourced from either direct air capture(DAC)or from point-source carbon capture(i.e.from industrial waste gases)to fulfill FMC commitments.Th

66、is is in line with the European Unions Renewable Energy Directive(RED II)20 as well as the UK SAF Mandate.21 Point-source capture includes the capture of biogenic CO2(e.g.carbon captured from a biomass power plant,or BECCS)or fossil CO2(e.g.carbon captured from a refinery).Fossil CO2 as a feedstock

67、is inherently less sustainable than DAC or biogenic CO2 because the carbon that will eventually be burned as jet fuel is still coming from a fossil source,while the carbon from DAC or biogenic CO2 was originally removed from the air.Therefore,beyond 2030 and the scope of the current FMC commitment,p

68、erspectives on this point are likely to change.*However,in the short term,one tonne of PtL jet fuel produced with point-source capture as a feedstock is still displacing one tonne of fossil jet fuel.Because DAC is more expensive and less available today,and in the long term,it is relatively easy to

69、switch CO2 feedstocks,point-source capture should be considered a viable feedstock for PtL,though non-biogenic point source CO2 must still be accounted for(i.e.by the point-source emitter,PtL fuel producer,aircraft owner,etc).If the project does source CO2 from DAC,it should ensure the electricity s

70、ource is low-carbon(e.g.renewable,nuclear).3.Synthesis and conversion.This accounts for 5-15%of total emissions,primarily from heat and electricity Note:The carbon intensity of PtL fuel does not assume any process synergies that could be realized from co-locating steps in the process(e.g.reuse of wa

71、ste heat),which have additional potential to reduce carbon intensity.4.Distribution.This accounts for 95%biogenic and has no or negative attributed land-use change.GFT using first-generation(1G)biomass feedstocks(e.g.primary crops like poplar,switchgrass)has some potential to meet the FMC threshold;

72、however,a project-level LCA should be conducted to determine carbon intensity.Key questions to ask GFT SAF suppliers:What feedstock is being used to produce the SAF?Is it a primary crop(1G)or a waste,byproduct,residue(2G)?If the feedstock is a mixed waste stream(e.g.,municipal solid waste(MSW),wood/

73、yard waste),what percentage biogenic content is it?Following CORSIA or a similar methodology,are there land-use change emissions attributed to the SAF?Following CORSIA or a similar methodology,is the final life-cycle carbon intensity at or below 13.35 gCO2e/MJ?Does the final product comply with ASTM

74、 D7566?EXECUTIVE SUMMARYDiagram of Gasification Fischer-Tropsch technical production pathways26FIGURE 51.Hydrocracking,isomerization and distillation.Source:Adapted from European Technology and Innovation Platform,Fischer-Tropsch Synthesis Bioenergy Fact Sheet,2021.ASTM-approved pathway(ASTM D7566)s

75、pecified at a 50%blend ratioTransport&distributionUpgrading1Fischer-Tropsch synthesisCultivationGasification&syngas conditioningCO2 impuritiesCxHyCrudeSAFSyngasBiomassOxygen/steamfeedstockSAFSAF production via biomass-to-liquid GFT pathwaySAF85 Technical Brief:Aviation Sector12Fischer-Tropsch is a p

76、rocess of converting(synthesis gas or syngas)composed of CO and H2 into SAF.It was developed in the 1920s by Franz Fischer and Hans Tropsch and theoretically can take any feedstock that can supply CO and H2 components(including fossil fuels,biomass,and synthetic H2 and CO2 which were discussed in th

77、e PtL deep dive).26 This section is focused on converting biomass sources into SAF,also known as biomass-to-liquids.The technical process is laid out in Figure 5.The most important factor determining whether a project will meet the FMC threshold is feedstock.Biomass feedstocks for GFT fall into two

78、categories:first-generation(1G)and second-generation(2G).“First-generation feedstocks”refer to primary crops grown for the purpose of using as feedstock for biofuel production.This includes poplar,switchgrass,willow,eucalyptus and miscanthus.“Second-generation feedstocks”,on the other hand,refer to

79、waste products,byproducts and other residues,including 95%biogenic municipal solid waste(MSW),forest residues,corn stover and wheat grass.The main difference in emissions lies in feedstock cultivation,where 1G feedstocks tend to have 2-3x the emissions of 2G feedstocks,and in land-use change,where 2

80、G feedstocks typically have no significant associated emissions.For MSW,which typically has a wide range of biogenic content,CORSIA has published a formula for calculating the default value by percentage of non-biogenic content.The reason this formula exists is that fuel combustion emissions must be

81、 counted for SAF produced using non-biogenic content.As this content goes up,counted fuel combustion emissions rise proportionally.However,while unlikely,if the MSW is 95%biogenic,its default value is within the FMC threshold.While it is not included in the default value,CORSIA additionally allows c

82、redits for avoided emissions from landfills(LECs)and credits for additional material recovery(RECs),which can be understood in detail in the“CORSIA Methodology for Calculating Actual Life Cycle Emissions Values”document.27Emissions profile of first-generation vs second-generation feedstocks(gCO2e/MJ

83、)FIGURE 61.Includes poplar,switchgrass,willow,eucalyptus;excludes miscanthus as an outlier,which is covered separately.2.Includes MSW(95%biogenic),forest residues,corn stover,and wheat straw.3.Bar totals 99%due to rounding error.4.Combustion emissions only counted from non-biogenic content,primarily

84、 from MSW.Feedstock cultivation and collectionFeedstock transportationFeedstock-to-fuel conversionFuel transportationFuel combustion4Land-use change 23%5%7%17%48%First generation(1G)feedstocks 1Second generation(2G)feedstocks 2,3 5%9%19%39%27%10-205-10SAF85 Technical Brief:Aviation Sector13Additiona

85、l analyses5Other factors affect compliance with the FMC commitment,including carbon capture and carbon accounting methodologies.Figure 7 shows the potential of each pathway to meet the FMC commitment threshold if carbon capture is used throughout the fuel conversion process,assuming a 90%capture rat

86、e,28 which the IEA describes as typical for industrial plants operating today.In this analysis,carbon capture was only symbolically applied to the fuel conversion emissions(i.e.emissions from feedstock cultivation,transportation and land-use change would not be eligible for carbon capture).The resul

87、ts show that many HEFA and AtJ pathways have the potential to meet the FMC commitment threshold if carbon capture is used;however,SIP remains beyond the threshold.No analysis was conducted on the technical feasibility of carbon capture on these processes,and there are no SAF plants today using carbo

88、n capture.For a new SAF project claiming to use carbon capture,these values should not be taken as default and a project-level LCA should still be conducted by the supplier.Impact of carbon capture on SAF pathways5.1SAF85 Technical Brief:Aviation Sector14Theoretical impact of carbon capture on SAF p

89、athways potential to meet FMC commitment threshold(gCO2e/MJ)FIGURE 7DefaultCarbon capture(90%capture rate)Commitment thresholdWaste gasesSugarcaneSugarbeet662923222221171444443330294Corn grainSwitchgrassSugarcaneAg residuesForest residuesMiscanthusCorn grainSwitchgrassMolassesSugarcaneCorn stoverFor

90、est residuesMiscanthus10134332525671628769-98649363329242054233027108-6Palm oilHEFAIsobutanol AtJEthanol AtJSIPMicrobiologic conversionRapeseed oilSoy oilCamelina oilTallowJatrophaCarinata oilPFADCorn oilUsed cooking oil777366625417141191054Source:CORSIA,FMC analysis and IEA.Another variable that is

91、 project-specific and makes up a large portion of emissions for certain pathways is induced land-use change(ILUC).CORSIA defines ILUC to include three major sources of emissions:291.Emissions due to changes in vegetative living biomass(natural vegetation and average agricultural landscape)carbon sto

92、ck2.Emissions due to changes in soil carbon stock3.Emissions debt equivalent to forgone carbon sequestrationImpact of induced land-use change of SAF pathways5.2SAF85 Technical Brief:Aviation Sector15CORSIA has triangulated the results of two models that estimate ILUC at both global and regional leve

93、ls for SAF pathways that have available data.CORSIA also labels some pathways as“low risk”for ILUC,30 particularly:1.Feedstocks that do not result in expansion of global agricultural land use for their production 2.Wastes,residues and by-products3.Feedstocks that have yields per surface unit signifi

94、cantly higher than terrestrial crops(e.g.some algal feedstocks)Because the FMC commitment specifically includes ILUC in its calculation,it is necessary to calculate or estimate land-use change at the project level for any SAF pathway that has a non-zero ILUC default value.Impact of ILUC on SAF pathw

95、ays potential to meet FMC commitment threshold(gCO2e/MJ)FIGURE 8DefaultNo land-use changeCommitment thresholdWaste gasesSugarcaneSugarbeet6629232222211714444433322929Corn grainSwitchgrassSugarcaneAg residuesForest residuesMiscanthusCorn grainSwitchgrassMolassesSugarcaneCorn stoverForest residuesMisc

96、anthus101343325256629242525998649363329242056432724292420Palm oilHEFAIsobutanol AtJEthanol AtJSIPMicrobiologic conversionRapeseed oilSoy oilCamelina oilTallowJatrophaCarinata oilPFADCorn oilUsed cooking oil777337474029232222211714Source:CORSIA,FMC analysis and IEA.Figure 8 shows the impact of elimin

97、ating ILUC(i.e.if assumed ILUC was zero unless the default ILUC value is negative)for each SAF pathway.SAF85 Technical Brief:Aviation Sector16As Figure 8 demonstrates there are no SAF pathways that were previously low likelihood of meeting the FMC commitment threshold that,with the minimization of I

98、LUC,are able to meet the FMC threshold.Many values do not change because those pathways did not have attributed land-use change to begin with.This analysis does not consider a situation where a pathway has negative ILUC emissions(that was not already negative in the default value).If a project claim

99、s to have negative ILUC,a project-specific LCA is needed to assess the carbon intensity of the SAF.Please note that different carbon emissions methodologies may treat direct and indirect land-use change differently as well.CORSIA is not the only standard and emissions calculation methodology that ex

100、ists today.Other similar frameworks include the European Unions recast Renewable Energy Directive(RED II),the UK Renewable Transport Fuel Obligation(RTFO)and the US Greenhouse Gases,Regulated Emissions&Energy Use in Transportation(GREET)models.Comparison of CORSIA to other standards and emissions me

101、thodologies5.3Comparison of relevant standards and emissions methodologiesFIGURE 91.EU baseline is not for SAF specifically,but rather generally for advanced biofuels(e.g.biodiesel,ethanol).Carbon Offsetting and Reduction Scheme for International AviationICAO,US 40B SAF credit,EU ETS,CAASAdopted byW

102、hat qualifies as a SAFMethodologyReduction of 10%or more from 89 gCO2e/MJ baselineTotal emissions Emissions from feedstock cultivationEmissions from feedstock harvesting,collection and recoveryFeedstock processing and extractionFeedstock transportationFeedstock-to-fuel conversionFuel transportation&

103、distributionFuel combustionLand use changeTotal emissions Extraction or cultivation of raw materialsCarbon stock changes caused by land-use changeProcessingTransport and distributionFuel useSoil carbon accumulation via improved agricultural mgmtCarbon capture and geological storageCarbon capture and

104、 replacementExcess electricity from cogenerationTotal emissions Extraction or cultivation of raw materialsCarbon stock changes caused by land-use changeProcessingTransport and distributionFuel useSoil carbon accumulation via improved agricultural mgmtCarbon capture and geological storageCarbon captu

105、re and replacementFuel production,transport between intermediate facilities,and transport to blending terminals and airportsCombustion(i.e.non-CO emissions from SAF combustion)Indirect effectsValorized co-productsTotal emissions Feedstock growing,harvesting,transporting and processing of primary fee

106、dstock materialCarbon capture and sequestration(for ethanol only)Induced land use changeOther cropsLivestockRice methaneCORSIARenewable Energy DirectiveRefuelEU AviationReduction of 70%or more from 94 gCO2e/MJ baseline1RED IIGHGs,Regulated Emissions,&Energy Use in TransportationUS 40B SAF creditRedu

107、ction of 50%or more from 89 gCO2e/MJ baselineGREETUK aviation industry(expected to begin 2025)Reduction of 40%or more from 89 gCO2e/MJ baselineUK SAF Mandate2SAF85 Technical Brief:Aviation Sector17The Renewable Energy Directive underpins a methodology for calculating emissions of biofuels that have

108、been adopted by the ReFuelEU Aviation SAF mandate.31 Whereas CORSIA only requires a GHG emissions reduction above 10%from fossil fuels,RED II requires a reduction above 70%.This has no implications for FMC specifically because the FMC commitment threshold is higher,at 85%.RED II does publish default

109、 values.However,these do not include SAF specifically,but rather other biofuels including biodiesel,biogas and ethanol.Therefore,they cannot be directly compared to CORSIA.Finally,while the exact language of the calculation methodology differs from CORSIA,both largely include the same components.The

110、 main differences lie in RED IIs subtraction of emissions from carbon capture,soil accumulation,and excess electricity from cogeneration,and the lack of a standalone entry for indirect land use changes.*CORSIA does not have specific guidance about the application of carbon capture or excess electric

111、ity and it includes soil accumulation emissions in its calculation of ILUC.Additionally,both methodologies specifically exclude emissions from equipment/machinery manufacturing.The UK SAF mandate is a regulatory measure to deliver UK GHG emissions reductions from the aviation sector in line with the

112、 UK governments 2022 Jet Zero Strategy.32 SAF certificates in the UK have been tradeable under the Renewable Transport Fuel Obligation(RTFO)since 2018,however,the UK SAF mandate,for which detailed guidance was released in April 2024,will replace this initiative.It is set to begin in 2025 and will ke

113、ep the RTFOs emissions calculation methodology.This methodology follows very similarly to RED II.33 The most important difference is that the UK SAF mandates calculation methodology does not include a subtraction for emissions from excess electricity from cogeneration.The UK government has decided t

114、hat while total default values will not be provided,disaggregated default values will be provided for downstream emissions,which will be published in upcoming mandate guidance.GHGs,Regulated Emissions and Energy Use in Transportation(GREET)is a collection of life-cycle emissions calculation methodol

115、ogies and models developed by the Argonne National Laboratory for companies to assess the emissions intensity of sustainable fuels.34 In April 2024,the Argonne National Laboratory released a new GREET model for SAF,which has been approved for companies to use to capture the 40B SAF tax credit laid o

116、ut in the Inflation Reduction Act(IRA).35 There are also voluntary certifications from RSB and ISSC,such as the use of CORSIA or any similar methodology.The new GREET model has now been approved as a similar methodology.36 GREET does not supply or plan to supply default values for SAF pathways,but d

117、oes provide an emissions calculator Excel file that can be used to estimate the LCA of a specific project.It also at this point only covers seven SAF pathways:1.US soybean HEFA2.US and Canadian canola/rapeseed HEFA3.Tallow HEFA4.Used cooking oil(UCO)HEFA5.US distillers corn oil HEFA6.US corn AtJ eth

118、anol7.Brazilian sugarcane AtJ ethanolThe implication of this is that for other SAF pathways(notably GFT and PtL which are of high interest for the FMC threshold),CORSIA remains the primary emissions calculation methodology to access the 40B SAF tax credit.While the language of GREET is considerably

119、different than CORSIA,RED II,or the UK SAF mandate,in practice,these methodologies remain very similar.The key difference is that GREET allows for the subtraction of emissions from valorized co-products.This means that if a co-product(e.g.distillers corn oil from ethanol AtJ)of SAF production is sol

120、d by the oil,ethanol,or SAF producer or otherwise productively used,it can qualify for a credit towards the SAFs total emissions.The implications are that,in the United States,a SAF plant that can produce approved co-products(list available in the GREET user manual)37 may have a lower carbon intensi

121、ty using the GREET methodology than using CORSIA.Beyond government-driven methodologies like RED II,the UK SAF mandate and GREET,there are other GHG methodologies and certification frameworks developed by non-governmental organizations,including certifications developed by the Roundtable on Sustaina

122、ble Biomaterials(RSB)38 and the International Sustainability and Carbon Certification(ISCC).39 Both offer multiple certifications including RSB Global Fuels Certification and ISCC PLUS,that are based on sustainability principles developed by these organizations as well as certifications that specifi

123、cally meet the underlying criteria for CORSIA(internationally)and RED II(in the EU).*RED II however sets limits on the use of biofuels that present high ILUC risks or a potentially significant expansion in land with high carbon stock.SAF85 Technical Brief:Aviation Sector18RSB EU RED Fuel Certificati

124、on and ISCC EU Certification ensure compliance with EU sustainability criteria and traceability requirements for biofuels and bioliquids.It is important to note that ISCC EU is already formally recognized by the EU while RSB EU RED Fuel Certification is currently in the process of being recognized.A

125、dditionally,RSB CORSIA Certification and ISCC CORSIA Certification ensure eligibility under CORSIA,and both are formally recognized by ICAO.The FMC commitment language specifies that“CORSIA or similar frameworks”can be used.GREET,RED II and the UK SAF Mandate and other methodologies that ensure comp

126、liance with either CORSIA or these frameworks should therefore be considered acceptable to calculate life cycle emissions for the geographies and pathways they include in scope.This document has focused on SAF pathways that are officially recognized by CORSIA or are otherwise of high interest to mem

127、bers based on future viability and/or potential to meet the 85%commitment threshold(e.g.PtL).However,it is likely that in the future other SAF pathways will continue to be developed.One example that is very nascent,but with high potential,is renewable natural gas(RNG)to SAF via Fischer Tropsch synth

128、esis or Methanol-to-Jet conversion.40 RNG,also known as biomethane,is a refined biogas,which can be produced through anaerobic digestion of biomass waste,and is an established,scalable technology today.41 Due to its nature as a waste feedstock(i.e.minimal ILUC and feedstock cultivation emissions)and

129、 use of power-to-liquids conversion processes RNG to SAF could have the potential to meet the FMC threshold,but it has not been explored in depth given the nascency of the pathway.As a general guideline,a project-level LCA should be conducted using CORSIA or similar methodology on any novel SAF path

130、way that is not specified in this document to confirm that it meets the FMC threshold.Additionally,it should be confirmed that the novel SAF pathway in question is approved under ASTM 7566.Novel SAF pathways not specified in this document5.4CORSIA default values for miscanthus attribute to it the hi

131、ghest negative ILUC emissions of all other feedstocks.This suggests that miscanthus AtJ SAF would well be within the FMC commitment threshold,and miscanthus GFT SAF could even reach a negative emissions value,despite the rule of thumb framework provided(Figure 3).Miscanthus could achieve negative IL

132、UC emissions due to its unique ability to“store roughly half of the carbon it removes from the air below ground,building extensive root and microbial systems that enrich soil.”42 This means that for every tonne of CO2 in harvested miscanthus biomass,another tonne of CO2 could be stored underground.O

133、ther feedstocks like jathropa,carinata and brassica may also reach high negative ILUC emissions according to the CORSIA default values.There are very few cases to date of such feedstocks being used for SAF,primarily in the United States,however,they do claim over 100%GHG emissions reduction compared

134、 to conventional jet fuel.While these early findings indicate there may be promising and unique feedstocks for multiple SAF technology pathways with a high potential to meet the FMC threshold,FMC recommends that a more detailed assessment of the ILUC implications is conducted when fulfilling the SAF

135、85 FMC commitment through fuels produced from such feedstocks.Miscanthus and other feedstocks5.5SAF85 Technical Brief:Aviation Sector19ContributorsProductionAuthor Zachary KaplanConsultant,Boston Consulting GroupWorld Economic ForumGiorgio ParoliniLead,Aviation Decarbonization,Net ZeroRosa Esi Ennis

136、onSpecialist,Freight Decarbonization,First Movers CoalitionBoston Consulting GroupCiara CorbeilPrincipal Martin FethManaging Director&Partner Ilshat HarisManaging Director&Partner Cornelius PieperManaging Director&Senior PartnerAnna TempleAssociate DirectorBianca Gay-FulconisDesigner,1-Pact EditionT

137、anya KorniichukIllustrator,1-Pact EditionMark SchulmanEditor,World Economic ForumSAF85 Technical Brief:Aviation Sector20Endnotes1.Carbon Offsetting and Reduction Scheme for International Aviation(CORSIA).(2023,July).International Civil Aviation Organization.Retrieved from https:/www.icao.int/environ

138、mental-protection/CORSIA/Pages/default.aspx.2.Reducing Emissions from Aviation.(n.d.)European Commission.Retrieved from https:/climate.ec.europa.eu/eu-action/transport/reducing-emissions-aviation_en#:text=The%20Carbon%20Offsetting%20and%20Reduction,of%20their%20emissions%20after%202020.3.Treasury,IR

139、S issue guidance on Sustainable Aviation Fuel Credit.(2023,December 15).Internal Revenue Service.Retrieved from https:/www.irs.gov/newsroom/treasury-irs-issue-guidance-on-sustainable-aviation-fuel-credit.4.AVIATION SPECIFICATIONS 3 VERIFICATION BODY.(2023,January 1).Civil Aviation Authroity of Singa

140、pore.Retrieved from https:/www.caas.gov.sg/docs/default-source/corsia/aviation-specifications-3-verification-body_final.pdf.5.Guidelines to Determine Life Cycle Greenhouse Gas Emissions of Sustainable Aviation Fuel Production Pathways using 40BSAF-GREET 2024.(2024,April).U.S.Department of Energy.Ret

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143、 scalable and sustainable fuel supply perspective for aviation.(2022,June).Umwelt Bundesamt.Retrieved from https:/www.umweltbundesamt.de/sites/default/files/medien/376/publikationen/background_paper_power-to-liquids_aviation_2022.pdf.9.Bonomi,A.,Klein,B.C.,Chagas,M.F.,&Souza,N.R.D.(2018,December).Te

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151、ing the UK SAF Mandate.(2024,April).United Kingdom Department for Transport.Retrieved from https:/assets.publishing.service.gov.uk/media/662938db3b0122a378a7e722/creating-the-UK-saf-mandate-consultation-response.pdf.22.Section 45V Credit for Production of Clean Hydrogen;Section 48(a)(15)Election To

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169、evaSwitzerland Tel.:+41(0)22 869 1212Fax:+41(0)22 786 2744contactweforum.orgwww.weforum.orgThe World Economic Forum,committed to improving the state of the world,is the International Organization for Public-Private Cooperation.The Forum engages the foremost political,business and other leaders of society to shape global,regional and industry agendas.