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Assessing the Future Performance Characteristics of IC Engines. John B. Heywood Director, Sloan Automotive Laboratory Massachusetts Institute of Technplogy. “Present and Future Engines for Automobiles,” Engineering Foundation Conference Catania, Italy, June 1-5, 2003. 06/01/03. Topics.
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Assessing the Future Performance Characteristics of IC Engines John B. Heywood Director, Sloan Automotive Laboratory Massachusetts Institute of Technplogy “Present and Future Engines for Automobiles,” Engineering Foundation Conference Catania, Italy, June 1-5, 2003 06/01/03
Topics • Assessing the performance of future engine-in- • vehicle combinations • a. Approach and methodology • b. Results and interpretation • Discussion of key issues • Ranking the various options 06/01/03
Two MIT Analyses of Future Automotive Technologies • 1. “On the Road in 2020: A life-cycle analysis of new • automobile technologies, “M.A. Weiss, J.B. Heywood, • E.M. Drake, A. Schafer, and F. AuYeung, MIT Energy • Lab. Report, MIT EL 00-003, October 2000. • http://web.mit.edu/energylab/www/ • “Comparative Assessment of Fuel Cell Cars,” M.A. • Weiss, J.B. Heywood, A. Schafer, and V.K. Natarajan, • MIT Lab. For Energy and Env. Report, MIT LFEE • 2003-001 RP, http://lfee.mit.edu/publications. 06/01/03
2020 Study Objectives • Assess the relative performance of future light-duty • vehicle technology and fuels, some 20 years from now. • Focus on energy consumption, CO2 emissions, and cost. • Do this on a “well to wheels” basis: energy source • through vehicle use and scrappage. • Assess the relative attractiveness of these technologies • and fuels to all the major stakeholders. • Focus on fuel, vehicle, and propulsion system technology • of average U.S. car. 06/01/03
Study Approach • Fuels • - Assess from available data energy consumption, • emissions and costs in delivering fuel to vehicle • Vehicles • - Use propulsion system, vehicle, drive cycle simulation to • predicts performance • - Evaluate a set of promising fuel, propulsion system and • vehicle technology combinations • - Match attributes of current average car (Toyota Camry) • 3. Total system • - Combine fuel production, vehicle production, and vehicle • use costs, energy consumption, CO2 • - Use templates (lists of relevant attributes) for all major • stakeholders to assess likely impact 06/01/03
Technology Options 1. Evolving mainstream technologies ‧Vehicle: better conventional materials (e.g. high strength steel), lower drag ‧Engine: higher power/volume, improved efficiency, lighter weight ‧Transmission: more gears, automatic/manual, continuously variable ‧Fuels: cleaner gasoline and diesel 2. Advanced technologies ‧Vehicle: lightweight materials (e.g. aluminum, magnesium, lower drag ‧Powertrain Hybrids (engine plus energy storage) Fuel cells (hydrogen fueled; liquid fueled with reformer) ‧Fuel: gasoline, diesel, natural gas, alcohols, hydrogen 06/01/03
Gasoline Engine: Future Potential ‧Spread of recently introduced innovations ‧Additional friction reduction opportunities ‧Smart cooling systems for engine temperature control ‧Cylinder cut out at lighter loads ‧Variable valve timing and lift at full and part load ‧Higher expansion ratio engines for increased efficiency ‧Variable compression ratio ‧Individual cylinder mixture and combustion control ‧Effective lean NOx catalysts ‧Gasoline direct-injection engine concepts ‧Boosted/turbocharged engine concepts ‧Engine plus battery hybrid systems ‧Etc. 06/01/03
Calculation logic: ICE – battery electric parallel drivetrain Driving Cycle Vehicle Resistance Logic Control Transmissiion Combustion Engine Fuel Comsumption Electric Motor Battery 06/01/03
IC Engine Model and Assumptions 1. IC engine indicated efficiency assumed constant: - Current, 38% SI engine; 48% diesel - Future, 41% SI engine; 52% diesel 2. Engine friction assumed constant: - Current tfmep = 165 kPa SIE; 180 kPa diesel - Future 25% reduction, SIE; 15% diesel 3. Brake efficiency obtained from indicated efficiency and friction data. 4. Maximum torque and power scaled by extrapolating historical trends (e.g. 20% increase in max. power) 06/01/03
Fuel Cycle Energy Use and CO2 06/01/03
Costs of Fuels, Ex-Tax, in 2020 Key Assumptions/Sensitivities Crude Oil: $12-32/B Gasoline Diesel Crude Oil: $12-32/B Piped Nat. Gas: $5.3 – 6.1 / GJ CNG Remote Gas: $0 – 1/GJ Capital Cost: $ 20-40k/B/D F-T Diesel Remote Gas: $0 – 1 / GJ Capital Cost: $ 65-105k/T/D Methanol Hydrogen Piped Nat. Gas: $5.7 / GJ US Grid @ 5.1¢/kWh Incl. 30% Off-Peak Reduction Electric Power Ex-Tax Cost of Delivered Fuel, S/GJ 06/01/03
FIGURE 1. RELATIVE CONSUMPTION OF ON-BOARD FUEL ENERGY ■ MJ(LHV)/km as percentage of baseline vehicle fuel use ■ All other vehicles (except 2001 “reference”) are advanced 2020 designs ■ Driving cycle assumed is combined Federal cycles (55% urban, 45% highway) ■ Hatched areas for fuel cells show increase in energy use in integrated total system which requires Compromises in performance of individual system components 2001 REFERENCE 2020 BASELINE GASOLINE ICE GASOLINE ICE HYBRID DIESEL ICE DIESEL ICE HYBRID HYDROGEN FC HYDROGEN FC HYBRID GASOLINE FC GASOLINE FC HYBRID 06/01/03
FIGURE 2. RELATIVE CONSUMPTION OF LIFE-CYCLE ENERGY ■ Total energy (LHV) from all sources consumed during vehicle lifetime ■ Shown as percentage of baseline vehicle energy consumption ■ Total energy includes vehicle operation and production of both vehicle and fuel 2001 REFERENCE 2020 BASELINE GASOLINE ICE GASOLINE ICE HYBRID DIESEL ICE DIESEL ICE HYBRID HYDROGEN FC HYDROGEN FC HYBRID GASOLINE FC GASOLINE FC HYBRID 06/01/03
Table 10. share of Life-Cycle Energy & GHG Note: Percentages for FCs are averages for “Component” and “Integrated” systems. Neither system varies more than about 1% from average. See Tables 8 & 9. 06/01/03
Summary: Future Powertrain and Vehicle Technologies 1. Significant potential for improving gasoline-engine vehicle energy consumption through continuing evolutionary changes (1-2% per year). 2. Diesel energy consumption benefit relative to equivalent gasoline technology is ~15%, longer-term (add 11% for miles per gallon), but cost is significantly higher. 3. Parallel ICE hybrid could provide about 30% lower energy consumption than non-hybrid equivalents in urban driving, at 20% increase in cost above baseline. 4. Fuel-cell vehicle projections underline importance of fuel supply. Direct hydrogen-fueled fuel cell hybrid vehicle energy consumption could be about 30% better than that of an equivalent ICE hybrid. Adding the fuel cycle for hydrogen removes this potential benefit. 06/01/03
Lessons from On the Road in 2020 1. Key question : Selecting the appropriate baseline: ‧Technology, vehicle, performance, drive cycle 2. Must compare alternatives on “well-to-wheels” and “cradle-to-grave” basis. 3. If hydrogen is the “fuel,” source of energy to produce the hydrogen is critical. 4. Many methodology challenges: e.g. double counting of benefits, realism of projections, rate of ongoing technology developments. 5. Costs will be critical. Costs for new technology alternatives are clearly speculative! 06/01/03
Time Scales for Significant U.S. Fleet Impact (see notes) 05/07/04