Current and Future U.S. Light-Duty Vehicle Pathways: Cradle-to-Grave

Jan 3, 2018 - This article presents a cradle-to-grave (C2G) assessment of greenhouse gas (GHG) emissions and costs for current (2015) and future (2025...
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Current and Future U.S. Light-Duty Vehicle Pathways: Cradle-to-Grave Lifecycle Greenhouse Gas Emissions and Economic Assessment Amgad Elgowainy, Jeongwoo Han, Jacob Ward, Fred Joseck, David Gohlke, Alicia Lindauer, Todd Ramsden, Mary J. Biddy, Mark Alexander, Steven Barnhart, Ian Sutherland, Laura Verduzco, and Timothy J. Wallington Environ. Sci. Technol., Just Accepted Manuscript • DOI: 10.1021/acs.est.7b06006 • Publication Date (Web): 03 Jan 2018 Downloaded from http://pubs.acs.org on January 10, 2018

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Current and Future U.S. Light-Duty Vehicle Pathways:

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Cradle-to-Grave Lifecycle Greenhouse Gas Emissions and Economic Assessment

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Amgad Elgowainy,a* Jeongwoo Han,a Jacob Ward,b Fred Joseck,b David Gohlke,a Alicia Lindauer,b Todd Ramsden,c Mary Biddy,c Mark Alexander,d Steven Barnhart,e Ian Sutherland,f Laura Verduzco,g and Timothy J. Wallingtonh a

Argonne National Laboratory, Argonne, IL 60439, USA United States Department of Energy, Washington, DC 20585, USA c National Renewable Energy Laboratory, Golden, CO 80401, USA d Electric Power Research Institute, Palo Alto, CA 94304, USA e FCA US LLC, Auburn Hills, MI 48326, USA f General Motors, Pontiac, MI 48340, USA g Chevron Corporation, Richmond, CA 94802, USA h Ford Motor Company, Dearborn, MI 48121, USA

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* Corresponding Author: [email protected]

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Abstract

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This article presents a cradle-to-grave (C2G) assessment of greenhouse gas (GHG) emissions and costs for current (2015) and future (2025–2030) light-duty vehicles. The analysis addressed both fuel cycle and vehicle manufacturing cycle for the following vehicle types: gasoline and diesel internal combustion engine vehicles (ICEVs), flex fuel vehicles, compressed natural gas (CNG) vehicles, hybrid electric vehicles (HEVs), hydrogen fuel cell electric vehicles (FCEVs), battery electric vehicles (BEVs), and plug-in hybrid electric vehicles (PHEVs). Gasoline ICEVs using current technology have C2G emissions of ~450 gCO2e/mi (grams of carbon dioxide equivalents per mile), while C2G emissions from HEVs, PHEVs, H2 FCEVs, and BEVs range from 300–350 gCO2e/mi. Future vehicle efficiency gains are expected to reduce emissions to ~350 gCO2/mi for ICEVs and ~250 gCO2e/mi for HEVs, PHEVs, FCEVs and BEVs. Utilizing low-carbon fuel pathways yields GHG reductions more than double those achieved by vehicle efficiency gains alone. Levelized costs of driving (LCDs) are in the range $0.25–$1.00/mi depending on timeframe and vehicle-fuel technology. In all cases, vehicle cost represents the major (60– 90%) contribution to LCDs. Currently, HEV and PHEV petroleum-fueled vehicles provide the most attractive cost in terms of avoided carbon emissions, although they offer lower potential GHG reductions. The ranges of LCD and cost of avoided carbon are narrower for the future technology pathways, reflecting the expected economic competitiveness of these alternative vehicles and fuels.

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1. Introduction

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The transportation sector is one of the largest contributors to greenhouse gas (GHG) emissions globally.

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Light-duty road vehicles are the major contributors to GHG emissions of the U.S. transportation sector.

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Curbing anthropogenic GHG emissions is among the most important long-term challenges facing

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society.1 More than190 countries have submitted an “Intended Nationally Determined Contribution” to

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the United Nations indicating their intention to achieve an economy-wide target of reducing GHG

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emissions.2 At least 18 U.S. states have also committed to GHG reduction targets.3 Concerted efforts by

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all players will be needed to meet these ambitious targets. Such efforts will include thorough

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environmental analysis, coupled with realistic assessments of feasibility, cost, and social impacts.

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Reducing GHG emissions from the transportation sector is one of the keys to achieving ambitious

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emissions reduction goals. In the United States, the transportation sector consumed 28 quadrillion British

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thermal units (Btu) of primary energy resources in 2015 — representing 28% of total national energy

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consumption; 92% of U.S. transportation energy was supplied by petroleum.4 The transportation sector is

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now the largest emitter of carbon dioxide in the United States,4 and total GHG emissions from

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transportation (in carbon-dioxide-equivalents, or CO2e) represent over one-quarter of total emissions

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nationally.5 Assessing the cost effectiveness of GHG mitigation technologies in the transportation sector

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is therefore a critical element of a national emissions reduction strategy.

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GHG emissions are commonly evaluated using life-cycle analysis (LCA), which also forms the basis for

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this study. Numerous LCA tools have been used to evaluate the GHG emissions associated with various

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vehicle-fuel technologies, including fossil fuels, biofuels, hydrogen fuel cell electric vehicles (FCEVs),

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hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVS), and battery electric vehicles

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(BEVs).6–13 Creyts et al. (2007) ranked transportation, building, and electricity generation technologies

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by amount and cost of GHG emissions reduction in the United States; the Creyts team was the first to

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publish marginal abatement cost (MAC) charts for a wide range of technologies.14 Sweeney et al. (2008)

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developed MAC curves for emissions reductions in California to guide the implementation of California’s

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Assembly Bill 32, which established a comprehensive program of regulatory and market mechanisms to

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significantly reduce GHG emissions.15 In 2010, Bloomberg New Energy Finance, an energy industry

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research firm, issued a research note on the carbon markets in North America suggesting that previous

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estimates of the carbon abatement cost were too optimistic and developed revised MAC curves

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accounting for new policies and sector-specific discount rates.16 More recently, in 2016, Roland Berger, a

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global strategy consulting firm headquartered in Munich, conducted a study of possible GHG abatement

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measures in the road transport sector for decarbonization through 2030 in the European Union (EU).17

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None of the aforementioned studies conducted a comprehensive cradle-to-grave LCA (including both fuel

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cycle and vehicle cycle) of the U.S. light-duty vehicles (LDVs) to calculate the GHG emissions and costs

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of a wide range of vehicle-fuel technologies — highlighting the need for a comprehensive LCA and

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economic assessment focused on the U.S. transportation sector. To address this research gap, we

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conducted an independent, comprehensive, cradle-to-grave (C2G) (vehicle and fuel cycle) LCA of energy

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consumption, GHG emissions, vehicle and fuel costs, carbon abatement costs, and technological readiness

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for current and future LDV/fuel technology pathways; the data and assumptions in our study were vetted

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by experts from the U.S. automotive and energy industries.

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In this paper, we present the C2G assessment of GHG emissions and costs for current (2015) and future

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(2025–2030) LDVs. The analysis includes gasoline and diesel internal combustion engine vehicles

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(ICEVs), flex-fuel vehicles (FFVs) fueled by E85 (85% corn ethanol blended with 15% gasoline by

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volume), compressed natural gas (CNG) vehicles, HEVs, FCEVs, BEVs, and PHEVs. To ensure a

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comprehensive study, we utilized bottom-up vehicle simulation models, LCA models, and techno-

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economic discounted cash flow models for the C2G analysis. The study resulted in an extensive, self-

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consistent, and transparent dataset to evaluate the effectiveness of different future LDV options in

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reducing GHG emissions. While the analysis focused on LDV road transport in the United States, the

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insights can be applied to other regions.

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2. Methods

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To facilitate technical discussion of the costs of mitigating GHG emissions generated by LDVs, which are

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responsible for approximately 60% of transportation-sector GHG emissions in the U.S.,18 our C2G

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assessment focused on a wide range of current and future vehicle-fuel technologies with potential for

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future deployment in the United States.19 Our analysis addressed every aspect of the vehicle and fuel life

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cycles, including manufacturing, end-of-life disposal (recycling and scrappage), and vehicle operation, as

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well as fuel feedstock production and transportation, fuel production, and fuel distribution. The study

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focused on fuel pathways deemed capable of scaling to 10% or more of the national LDV fleet by 2025–

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2030; these pathways were selected on the basis of availability of fuels and technological readiness19 (see

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also Supporting Information). The study is unique in investigating both the vehicle and fuel cycles of

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technology pathways presented in Figure 1, using a consistent set of system boundaries and an LCA

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method, as well as performance and cost data. The resulting comprehensive C2G assessment examines

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both GHG emissions and costs to determine the relative cost effectiveness of different technology options

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in mitigating GHG emissions. The analysis is also noteworthy because it involved a research

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collaboration among stakeholders in government, industry, and national laboratories. The input data and

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calculations used in the analysis are provided in the Supporting Information.

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Figure 1: Scope of C2G assessment, which includes fuel and vehicle life cycles. Inset table: List of fuels, vehicles using these fuels, and sources of fuels examined in this analysis. Abbreviations: CNG – compressed natural gas; LPG – liquefied petroleum gas; ICE – internal combustion engine; HEV – hybrid electric vehicle; PHEV – plug-in hybrid electric vehicle; FCEV – fuel cell electric vehicle; BEV – battery electric vehicle; E10 – 10% corn ethanol blended with 90% petroleum gasoline by volume; HRD – hydroprocessed renewable diesel; FAME – fatty acid methyl ester; GTL FTD – gas-to-liquid FischerTropsch diesel; E85 – 85% corn ethanol blended with 15% gasoline by volume; SMR – steam methane reforming; CCS – carbon capture and storage; PV – photovoltaics; NG ACC – natural gas advanced combined cycle.

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GHG emissions and energy use were calculated using the Greenhouse gas, Regulated Emissions, and

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Energy use in Transportation (GREET®) model developed at Argonne National Laboratory (Argonne).20

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Vehicle fuel economies and manufacturing costs were estimated using the Autonomie model,21 also

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developed at Argonne, by sizing components of the different vehicle architectures to deliver comparable

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operational performance (e.g., time to accelerate from 0–60 mph, maximum speed), thus eliminating

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important confounding factors. Autonomie cost results were compared to both real-world vehicle costs

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and other modeled costs from recent literature, including NRC 2013 22 and 2015 23, NPC 2010 24, and MIT

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2008 25. Autonomie modeled costs were largely consistent with recent work reported in the literature.

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Future modeled costs from the comparison studies fell within 30% of the Autonomie results, with the

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exception of the BEVs, which were modeled at significantly higher cost in NRC 2015 (BEV70) and NPC

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(BEV210). References to the comparison studies and an overview of comparison results are available in

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the Supporting Information.

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The costs to consumers for established fuels were based on the U.S. Energy Information Administration’s

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(EIA’s) 2015 Annual Energy Outlook,26 while techno-economic analysis models with consistent

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economic assumptions were used to estimate the costs for hydrogen and advanced bio-derived fuels. The

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robustness of the cost modeling was tested by examining multiple sensitivities. This study considered

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different vehicle ownership periods (3, 5, and 15 years), discount rates (3, 5, and 7%), manufacturing

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volumes (low=10,000–100,000 vehicles/year and high=500,000 vehicles/year), and projected ranges for

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future oil and other fuel/feedstock prices (details provided in Supporting Information).

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The fuels or energy carriers in this study included gasoline, ethanol, diesel, CNG, LPG, hydrogen, and

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electricity. For each of these fuels and their feedstocks, we examined the GHG emissions and costs for a

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current technology case and possible future technology production pathways. These fuels were used in

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ICEVs, FFVs fueled by E85, HEVs, hydrogen FCEVs (H2 FCEVs), BEVs with either 90 or 210 miles of

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range (BEV90 or BEV210), and PHEVs with 10 or 35 miles of all-electric range (PHEV10 or PHEV35).

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3. Results and Discussion

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3.1 Vehicle Cycle Emissions

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Figure 2 presents vehicle life-cycle GHG emissions by vehicle component for the current and future

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technology cases; additional details are provided in the Supporting Information. Total vehicle-

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manufacturing life-cycle emissions are between 8–12 tonnes CO2e for current vehicle technologies and 6–

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9 tonnes CO2e for the future cases. The decrease between the current and future cases mostly reflects the

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projected reductions in the CO2 burden of average U.S.-generated electricity. The current and future

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vehicle life-cycle emissions of 7.8 and 6.9 tonnes, respectively, for ICEVs correspond to 44 gCO2e/mi and

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39 gCO2e/mi when spread over an average 180,000 miles driven during the vehicle’s lifetime27 (see also

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Supporting Information). BEV210-manufacturing emissions of 9.8 and 7.3 tonnes for the current and

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future cases correspond to 55 gCO2e/mi and 41 gCO2e/mi. Batteries are assumed to last the life of the

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vehicle without replacement, and short-range BEVs (e.g., BEV90s) travel approximately 30% fewer miles

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than conventional vehicles.28 In general, the GHG emissions generated during the vehicle manufacturing

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cycle are one order of magnitude lower than the fuel cycle GHG emissions of the current gasoline ICEV

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(~400 gCO2e/mi).

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The 26% increase in vehicle-manufacturing GHG emissions for the BEV210 versus the gasoline ICEV

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using the current technology can be compared with increases of 27% reported by Notter et al. (2010),

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63% by Hawkins et al. (2013), and 39% by Kim and Wallington (2016).29,30,31 Estimates of the emissions

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burden associated with battery production in the current study, in the Notter et al. (2010) study, and in the

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Kim and Wallington (2016) study are in good agreement at approximately 2–3 tonnes CO2e, while the

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Hawkins et al. (2013) estimate is approximately 5 tonnes CO2e.

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Figure 2: Vehicle life-cycle GHG emissions for current (2015, left panel) and future (2025–2030), right panel) technology pathways.

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3.2 Cradle-to-Grave Emissions

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Figure 3 shows a selection of the calculated life-cycle GHG emissions from current vehicle-fuel

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technology pathways and from those deemed scalable in the 2025–2030 timeframe (following an

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assessment of technological readiness). From a C2G emissions perspective, which includes both fuel and

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vehicle life cycles, a midsize conventional ICEV today emits approximately 450 gCO2e/mi (black

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horizontal line in top left of Figure 3) when using E10. Corresponding GHG emissions from diesel ICEVs

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are approximately 15% lower, while emissions from BEVs operating on the average U.S. grid electricity

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mix in 2014 and H2 FCEVs fueled by hydrogen derived from natural gas reformation are approximately

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20–35% lower (horizontal black lines under H2 FCEV, BEV90, and BEV210 at the right of Figure 3). For

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ICEVs, 9–11% of the total emissions are from the vehicle cycle, for HEVs 13%, and for PHEVs and H2

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FCEVs 16–21%, while the remainder are generated during the fuel cycle.

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Figure 3. Emissions for different vehicle-fuel pathways. The horizontal black lines are emissions from today’s vehicles. Red lines are emissions assuming future vehicle efficiency gains but using current fuels. The vertical arrows show GHG emissions mitigation for vehicle and fuel changes (e.g., the gray arrows represent a conversion from conventional to pyrolysis fuels along with vehicle efficiency gains). Input data and calculations are provided in the Supporting Information.

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Looking to the future, vehicle energy efficiency improvements alone can potentially reduce per-mile C2G

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GHG emissions by up to 30% per vehicle for most vehicle-fuel pathways (comparing the black with the

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red horizontal lines in Figure 3). However, there are physical limits to vehicle energy efficiency gains,32

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and thus a system-level approach requires that advanced low-carbon fuels be used in energy-efficient

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vehicles to achieve deeper reductions in GHG emissions from the LDV technologies. Assuming large-

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scale availability, we find that gasoline produced via pyrolysis of forest residue can reduce C2G GHG

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emissions by nearly 60% relative to E10 gasoline; ethanol produced from fermentation of corn stover can

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reduce emissions by nearly 50%; and carbon-free renewable electricity sources (such as solar or wind)

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can reduce GHG emissions by over 80% for BEVs and H2 FCEVs. Therefore, by combining advanced

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vehicle and fuel technologies, GHG emissions can potentially be reduced by up to 70–90%. However, it

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should be noted that the total quantities of energy produced through these low-carbon pathways may be

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limited by their availability, geographical location, infrastructure and/or market constraints, and/or

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intermittency.

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3.3 Cradle-to-Grave Costs

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While Figure 3 shows that advanced vehicle and fuel technologies could clearly lead to deep reductions in

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GHG emissions compared with a conventional gasoline ICEV, impacts on the upfront vehicle purchase

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price and the levelized cost of driving (LCD) are decisive factors in the adoption of these vehicles by

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consumers. Figure 4 shows LCDs for current (2015, dark bars) and future (2025–2030, light bars)

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vehicle-fuel technologies, assuming high production volumes for all vehicle and fuel production

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technology pathways. The LCDs, including vehicle purchase and fuel cost, ranged from 24¢ per mile for

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current conventional gasoline ICEVs to 56¢ per mile for BEV210s, assuming high-volume manufacturing

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(~500k units/year). Low-volume manufacturing (10k–100k units/year) of components that are not

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currently mainstream, such as high-capacity battery packs and hydrogen fuel cell stacks, increases the

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estimated vehicle price by up to 70% (to as high as 93¢ per mile for BEV210s) compared with high-

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volume production. The data in Figure 4 were computed using a 15-year vehicle lifetime, to determine the

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LCD to all owners over the vehicle lifetime, and a 5% discount rate. Maintenance, insurance, parking,

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highway tolls, and other expenses (besides the purchase price of the vehicle and its fuel) were not

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included in the analysis, because these costs were assumed not to be major differentiators between the

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different technologies.

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In 2025–2030, ICEVs using conventional gasoline were determined to be the least expensive vehicle-fuel

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systems for the end user on a per-mile basis. LCDs ranged from 26¢ per mile for conventional gasoline

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ICEVs to 38¢ per mile for long-range BEVs using electricity derived from solar energy. The costs of

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other pathways include 31¢ per mile for corn-stover ethanol ICEVs, 28¢–30¢ per mile for PHEVs and H2

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FCEVs, and 34¢–38¢ per mile for BEVs. The central estimate of the future technology conventional

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ICEV is $2,110 more than the central estimate of the current technology version, due to advancement in

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engine and materials technologies.21

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3.4 Costs of Avoided GHG Emissions

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The costs of avoided GHG emissions for alternative vehicle-fuel pathways were calculated from the

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difference in the per-mile costs (shown in Figure 4) of the conventional gasoline ICEV baseline compared

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with the alternative technology divided by the difference in the per-mile GHG emissions of the alternative

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vehicle compared with the gasoline ICEV (shown in Figure 3). Figure 5 shows the results for selected

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high-volume current (dark bars) and future (light bars) technology pathways. The results for the future

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technology pathways indicate that the lowest-cost ICEV, PHEV, HEV, H2 FCEV, and BEV pathways

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have avoided GHG emission costs in the range of $90–$400/tonne CO2e, relative to an ICEV fueled by

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petroleum gasoline, while current technologies have a GHG emission cost of up to $1,100 for FCEV and

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BEV90, and $2,600 for BEV210. In a sensitivity analysis with a high oil price and a low discount rate, the

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cost of GHG mitigation was negative (money was saved while emissions were reduced at the same time)

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for high-efficiency hybrid vehicles and for PHEVs with a 10- to 35-mile electric range. The success of

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alternative technologies at scale will depend on several factors, including their cost-effectiveness in a

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competitive environment. The results in Figure 5 are based on the lowest-cost fuel for each vehicle type;

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details about these vehicle-fuel pathways, along with other potential and plausible energy-fuel pathways,

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are provided in the Supporting Information.

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Figure 4. Levelized cost of driving for current (2015, dark bars) and future (2025–2030, light bars) technology pathways. Low-volume production is represented by black diamonds. CNG and LPG vehicles are evaluated only for the current technology case.

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The x-axis scale in Figure 5 highlights the costs associated with reducing GHG emissions for future

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vehicle-fuel pathways compared with the incumbent future gasoline ICEV baseline, although with lager

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potential for GHG emissions reduction. To place these costs into perspective, a typical gasoline ICEV

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using current technology emits approximately 80 tonnes of CO2e over its lifetime of approximately

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180,000 miles on a C2G basis, equivalent to ~450 gCO2e/mi. Emissions reductions from the future

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vehicle-fuel pathways described above would have a 6–55% premium (total cost of driving over vehicle’s

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lifetime) compared to the baseline 2025–2030 ICEV using petroleum-based gasoline. As ownership costs

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(represented here in LCD terms) can be significantly higher for advanced vehicle-fuel technologies, GHG

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emissions reduction and other benefits of these advanced vehicle-fuel pathways should be examined with

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consideration to future affordability and the ability of all levels of society to access modes of personal

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transportation. Estimates of significant LCD increases for advanced vehicle-fuel technologies show the

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need for additional research and development to reduce costs.

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Figure 5. Cost of avoided GHGs for current (2015, dark bars) and future (2025–2030, light bars) technology pathways compared with a conventional gasoline ICEV (baseline). Lifetime costs for carbon mitigation using current technologies range from $170 to $2,700 per tonne. The lowest-cost future pathways are shown for each vehicle type, and range from $90 to $410 per tonne.

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3.5 Uncertainties

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Calculations of fuel consumption and vehicle costs were performed using the Autonomie automotive

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control system and simulation tool,21 which provides low, medium, and high (90th, 50th, and 10th

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percentile probability) estimates for future vehicle technology and cost progress. The results in Figures 4

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and 5 are based on the medium technology progress case and the average of the low and high cost

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progress cases (see Supporting Information). The research team investigated sensitivity to future vehicle

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costs using cost ranges that spanned the low and high estimates. As indicated by the lighter color bars in

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Figure 4, inclusion of vehicle cost uncertainties does not alter the relative ranking of the technologies, but

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for the low extremes of the cost ranges, inclusion of these uncertainties would substantially narrow the

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gap between the technologies. Table 1 lists the uncertainties in vehicle costs and their impacts on LCDs.

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Note that Table 1 shows the lowest cost advanced fuel pathway for each powertrain, see Supporting

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Information for costs of other fuels.

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Table 1. Range of future incremental vehicle costs, sensitivities of levelized cost of driving to vehicle costs, and sensitivity of abatement costs to vehicle cost and oil price.

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Incremental vehicle Sensitivity of Abatement cost & Abatement cost and Future vehicle cost relative to future LCD ($/mi) to sensitivity to vehicle sensitivity to oil type gasoline ICEV ($) a vehicle cost b cost ($/ton CO2e) price ($/ton CO2e) Gasoline ICEV ±780 ±0.006 240±30 c 240+75-220 Diesel ICEV 2350±1090 ±0.009 255±40 c 255+70-210 HEV 2070±1100 ±0.009 95±35 c 95+65-190 d PHEV10 2660±760 ±0.006 90±25 90+65-185 PHEV35 6390±1480 ±0.012 145±40 d 145+60-165 FCEV 6770±1990 ±0.016 210±65 e 210+65-210 BEV90 3570±2290 ±0.026 290±85 f 290+55-155 f BEV210 19,600±7430 ±0.057 410±185 410+50-150 a: medium value with range spanning high and low values from Autonomie model, relative to medium value for future ICEV; b: sensitivity of LCD to range of vehicle costs; c: pyrolysis liquid fuel; d: pyrolysis liquid fuel, wind electricity; e: SMR with CCS; f: wind electricity, see text and SI for details.

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The results shown in Figure 4 were obtained using future fuel costs from the reference case in the EIA’s

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2015 Annual Energy Outlook26 with a crude oil cost of $82/barrel corresponding to a fuel cost of

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$0.071/mi for gasoline ICEVs (shown in the bottom bar in Figure 4). The low- ($57/barrel) and high-oil

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price ($158/barrel) cases from EIA correspond to fuel costs of $0.055 and $0.117/mi. The high oil price

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extreme would add $0.046/mi to the LCD for the future conventional gasoline ICEV, and increase it to

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$0.30/mi, which is higher than the future HEV and PHEV10 pathways and comparable to the lowest cost

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future PHEV35 and FCEV pathways. It is well established that high oil prices make alternative

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technologies more attractive.

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For the high-oil-price case, several of the pathways have negative abatement costs (money saved and

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emissions reduced). We note that large-scale use of alternative technologies would reduce oil demand,

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making an assumption of high oil prices questionable. For further discussion of uncertainties, see the

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Supporting Information.

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3.6 Cost-effectiveness

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To assess cost effectiveness, the costs of the technologies in Figure 5 need to be compared with the

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benefits. The costs in Figure 5 can be compared to the social cost of CO2,33 which has been estimated by

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the U.S. Environmental Protection Agency to be $14–$152 per tonne in 2025–2030.34 The costs estimated

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for avoiding GHG emissions from LDVs shown in Figure 5 are higher than the externalities estimated for

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the social cost of CO2. Furthermore, while these alternative vehicle-fuel systems provide large GHG

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emissions reductions, they require further research and development to compete against the conventional

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systems available in the market today.

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This contextualization highlights the utility of the cost of avoided emissions as a metric for comparing

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different technologies. However, using the cost-of-avoided-emissions metric has limitations; the

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technologies considered in the analysis differ not only in terms of their lifetime GHG emissions but also

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in other important attributes, such as local air-quality-related emissions, reliance on different energy

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sources and fuels (e.g., petroleum, natural gas, ethanol, hydrogen, electricity), and functionality (e.g.,

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more limited range and longer refueling times for BEVs).

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The current work represents a comprehensive analysis of life-cycle GHG emissions and associated costs.

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While several well-to-wheel fuel-cycle assessments of the emissions abatement costs associated with

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LDVs have been published, the results from these previous assessments diverge widely. As an example, a

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McKinsey report concludes that carbon abatement costs in the U.S. LDV sector are generally negative,35

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while the report from Roland Berger finds positive abatement costs for LDV technologies in the EU in the

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range of 100–800 EUR/tonne.17 The figures from Roland Berger are broadly consistent with our results

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for the United States, although further work is needed to compare and contrast the key assumptions across

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studies. As mentioned earlier, details regarding input data, assumptions, and calculations for the present

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work are provided in the Supporting Information.

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To achieve large-scale GHG emissions reductions in the United States, emissions reductions will be

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required in all sectors: electric power generation, residential, commercial, industrial, and transportation.

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The findings presented here highlight the challenges in achieving large GHG emissions reductions from

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LDVs and can help policymakers develop a more informed approach to addressing GHG emissions

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reductions.

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Acknowledgements and Disclaimer

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The research effort was supported by the Fuel Cell Technologies Office and the Vehicle Technologies

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Office of the U.S. Department of Energy’s Office of Energy Efficiency and Renewable Energy under

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Contract Number DE-AC02-06CH11357. The views and opinions of the authors expressed herein do not

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necessarily state or reflect those of the U.S. Government or any agency thereof. Neither the U.S.

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Government nor any agency thereof, nor any of their employees, makes any warranty, expressed or

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implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of

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any information, apparatus, product, or process disclosed, or represents that its use would not infringe

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privately owned rights. U.S. DRIVE Cradle-to-Grave Working Group members contributed to this report

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in a variety of ways, ranging from full-time work in multiple study areas, to research or analysis on a

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specific topic, to drafting and reviewing proposed materials. Involvement in these activities should not be

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construed as endorsement or agreement with all of the assumptions, analyses, statements, and findings in

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the report. Any views and opinions expressed in the report are those of the authors and do not necessarily

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reflect the views of Argonne National Laboratory, Chevron Corporation, Electric Power Research

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Institute, Exxon Mobil Corporation, FCA US LLC, Ford Motor Company, General Motors, National

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Renewable Energy Laboratory, Phillips 66 Company, Shell Oil Products US, or the U.S. Department of

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Energy. Ford Motor Company (Ford) does not expressly or impliedly warrant, nor assume any

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responsibility, for the accuracy, completeness, or usefulness of any information, apparatus, product, or

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process disclosed, nor represent that its use would not infringe the rights of third parties. Reference to any

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commercial product or process does not constitute its endorsement. This article does not provide

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financial, safety, medical, consumer product, or public policy advice or recommendation. Readers should

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independently replicate all experiments, calculations, and results. The views and opinions expressed are

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of the authors and do not necessarily reflect those of Ford. This disclaimer may not be removed, altered,

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superseded or modified without prior Ford permission.

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Supporting Information

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The supporting information include the following supporting material:

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- Vehicle scale assumptions by technology

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- Fuel production pathways considered in the cradle-to-grave analysis

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- Annual vehicle mileage assumptions

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- Vehicle fuel economy

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- Summary of fuel cost inputs

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- Summary of vehicle costs compared with other studies

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- The levelized cost of driving calculation formula

349

- Uncertainty analysis

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