What is a Well-to-Wheel Analysis?

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2 What is a Well-to-Wheel Analysis? A rigorous examination of the entire process of creating and using fuels to provide power to the wheels of a vehicle, resulting in an assessment of requisite energy consumption and corresponding greenhouse gas (GHG) emissions Well-to-Tank (Fuel): Accounting of energy consumption and GHG emissions over the entire fuel pathway, from feedstock to fuel dispenser nozzle Tank-to-Wheel (Vehicle): Accounting of the energy consumption and GHG emissions resulting from moving the vehicle through its drive cycle Well-to-Wheel denotes the combination of the fuel and vehicle portions

3 Two Illustrative Well-to-Wheel Pathways Well-to-Tank Tank-to-Wheel

4 Background Study commissioned by GM Well-to-Tank (Fuel) work conducted by Ludwig Bölkow Systemtechnik (LBST) with input from BP, ExxonMobil, Shell and TotalFinaElf Tank-to-Wheel (Vehicle) work performed by GM Considers 36 fuel pathways and 18 conventional and advanced powertrain systems, targeted to 2010 timeframe North American WTW study unveiled at Hart World Fuel Conference, New Orleans, March 2001

5 Motivation for a European Well-to-Wheel Study As Follow-Up to the North American Study Fuel Related Different crude oil/refining scenarios Different natural gas supply factors at play Different electricity grid mix Affords the opportunity to explore additional renewables-based pathways Vehicle Related Different vehicle and drive cycle Different customer performance requirements ACEA commitment to reduce CO 2 emissions by 2008

6 Well-to-Tank Pathways Analyzed* Feedstock Oil-Based (3) Natural Gas-Based (16) Electricity (6) Biomass-Based (11) Total pathways examined: Fuel Gasoline, Diesel, Naphtha CNG, Methanol, Fischer-Tropsch Diesel and Naphtha (GTL), Compressed Hydrogen, Liquid Hydrogen Electricity, Compressed Hydrogen, Liquid Hydrogen Compressed Hydrogen, Methanol, Ethanol, Hydrocarbon Liquids, Bio-ester, ETBE, MTBE 36 [+ 58 variants] * production potential may be limited for some pathways in 2010 timeframe

7 European Tank-to-Wheel Analysis (Vehicle Pathways) Baseline vehicle: Opel Zafira Duty cycle: European Driving Cycle (EDC) All vehicle concepts modeled to meet same set of European customer performance requirements Technologies targeted for the 2010 time frame Advanced IC engine and transmission technologies Advanced vehicle level technologies Hybrid system technologies Fuel processor and fuel cell systems in hybrid and non-hybrid architectures

8 Vehicle Propulsion Systems Analyzed IC Engine Fuel Cell IC Engine Hybrid Fuel Cell Hybrid Gasoline X X X X +Advanced Powertrain Diesel X X F-T Diesel X X CNG X X (optimized mono-fuel) Methanol X X Ethanol (E100) X X Hydrogen X X X X

9 Consistent Real World Vehicle Performance Requirements European Minivan Class Range (20 km ZEV Range for HEVs) (km) 650 Acceleration Time, km/h (sec) 12 4 Acceleration Time, 0-50 km/h (sec) Top Speed (Continuous) (km/h) Acceleration in Top Gear, (Elasticity) km/h (sec) Gradeability at 90 km/h for 20 minutes (%) 6 30 Maximum Gradeability (%) 4.5 Maximum Acceleration (m/s 2 )

10 Tank-to-Wheel Energy Consumption Conventional (Non-Hybrid Drives)

11 Tank-to-Wheel Energy Consumption Conventional (Non-Hybrid Drives)

12 Parallel Hybrid Powertrain Architecture Battery Inv Inv Excess engine power may be used to charge battery Regeneration Motor Gear Gear Motor can assist engine Vehicle may be launched with battery Engine Multi-Speed Transmission Engine can operate at low speed and high load Engine may be disconnected during standstill, deceleration and launch

13 Tank-to-Wheel Energy Consumption Hybrid Drives

14 Tank-to-Wheel Energy Consumption Hybrid Drives

15 Well-to-Wheel Energy Consumption

16 Well-to-Wheel Energy Consumption

17 Well-to-Wheel Energy Consumption

18 Well-to-Wheel Greenhouse Gas* Emissions * CO 2, N 2 O, CH 4

19 Well-to-Wheel Greenhouse Gas Emissions

20 Well-to-Wheel Greenhouse Gas Emissions

21 Well-to-Wheel Greenhouse Gas Emissions

22 Well-to-Wheel Conclusions (1/2) Findings of the present work are generally consistent with those of the GM-Argonne North American WTW study in terms of relative rankings of the fuel-powertrain combinations; absolute WTW values are lower primarily due to the smaller (lower mass) reference vehicle used in the European Study Hybridization reduces fuel consumption in all propulsion systems, however the benefits are larger for internal combustion (IC) engines than for fuel cells because of the fuel cell s superior part-load efficiency relative to IC engines Hydrogen fuel cell vehicles running on hydrogen from reformed natural gas offer reduced GHG emissions relative to gasoline and diesel IC engine vehicles The source of natural gas feedstock has a large impact on GHG emissions for natural gas-based pathways Fuel cell vehicles offer the potential to greatly reduce or eliminate WTW GHG emissions when fueled with hydrogen from renewable sources

23 Well-to-Wheel Conclusions (2/2) Methanol fuel cell vehicles offer no benefit relative to gasoline or diesel IC engine vehicles or gasoline processor fuel cell vehicles Electrolysis-based hydrogen generates high GHG emissions with electricity from the traditional electric grid mix, and near-zero GHGs when the electricity is produced renewably Optimized CNG engine vehicles provide GHG emission benefits compared with gasoline IC engine vehicles, however, they do not provide a benefit on well-to-wheel energy consumption Biofuels offer reduced GHGs, however, the magnitude of improvement depends on the assumptions about N 2 O emissions from the crops Fischer-Tropsch diesel IC engine vehicles yield higher energy consumption and GHG emissions than oil-based diesel IC engine vehicles IC engine vehicles fueled with liquid hydrogen from natural gas offer zero vehicle CO 2 emissions, but result in higher WTW GHGs than either conventional gasoline or diesel IC engine vehicles

24 Next Steps Finalize and publish European Well-to-Wheel study for public release this summer Study will be available at Participate in Joint European Well-to-Wheel Study (under EUCAR and CONCAWE auspices) Collaborate with other similar efforts Prof. Ishitani, Tokyo University Prof. Heywood, MIT

25 Acknowledgments European Well-to-Wheels Study Working Group Andrew Armstrong, BP Norman Brinkman, GM Jean Cadu, Shell Raj Choudhury, GM David Masten, GM Olivier Dautrebande, TotalFinaElf Martin Fasse, GM Volker Formanski, GM Dieter Hasenauer, GM Daniel Le Breton, TotalFinaElf Moshe Miller, Advanced Development Corp. Stephan Noodt, Fiat-GM Powertrain Joachim Quarg, Fiat-GM Powertrain David Rickeard, Exxon Mobil Jörg Schindler, LBST Christoph Schmidt, GM Trudy Weber, GM Hans Weidner, GM Werner Weindorf, LBST Reinhold Wurster, LBST