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

1. Assessing the performance of future engine-in-

vehicle combinations

a. Approach and methodology

b. Results and interpretation

2. Discussion of key issues

3. 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/

2. “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

1. Assess the relative performance of future light-duty

vehicle technology and fuels, some 20 years from now.

2. Focus on energy consumption, CO2 emissions, and cost.

3. Do this on a “well to wheels” basis: energy source

through vehicle use and scrappage.

4 Assess the relative attractiveness of these technologies

and fuels to all the major stakeholders.

5. Focus on fuel, vehicle, and propulsion system technology

of average U.S. car.

06/01/03

Study Approach

1. Fuels

- Assess from available data energy consumption,

emissions and costs in delivering fuel to vehicle

2. 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

Electric

Motor

Combustion

Engine

Battery

Fuel

Comsumption

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

Table 7. Overall Fuel Cell System Efficiencies

Net Output

Energy, %

Of Peak

100 X Net DC Output Energy / Fuel LHV

100% Hydrogen Fuel Gasoline Reformate Fuel

Components Integrated Components Integrated

5

10

20

40

60

80

100

76

75

74

69

65

61

53

71

71

70

65

61

58

50

46

50

49

46

44

41

36

42

45

44

42

39

37

33

06/01/03

Fuel Cycle Energy Use and CO2

Fuel Energy Use

MJ/MJ Efficiency

GHG

gC/MJ

Gasoline 0.21 83% 4.9

Diesel 0.14 88% 3.3

CNG 0.18 85% 4.2

F-T Diesel 0.93 52% 8.9

Methanol 0.54 65% 5.9

Hydrogen 0.77 56% 36

Electric Power 2.16 32% 5406/01/03

Costs of Fuels, Ex-Tax, in 2020

Gasoline

Diesel

CNG

F-T Diesel

Methanol

Hydrogen

Electric Power

Ex-Tax Cost of Delivered Fuel, S/GJ

Key Assumptions/Sensitivities

Crude Oil: $12-32/B

Crude Oil: $12-32/B

Piped Nat. Gas: $5.3 – 6.1 / GJ

Remote Gas: $0 – 1/GJCapital Cost: $ 20-40k/B/D

Remote Gas: $0 – 1 / GJCapital Cost: $ 65-105k/T/D

Piped Nat. Gas: $5.7 / GJ

US Grid @ 5.1¢/kWhIncl. 30% Off-Peak Reduction

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

Vehicle Energy, % of Total GHG, % of Total

Operation Fuel

Cycle

Vehicle

Mfg.

Operation Fuel

Cycle

Vehicle

Mfg.

2001 Reference 75 16 9 74 18 8

2020 Baseline 74 15 11 71 18 11

Gasoline ICE 73 15 12 72 18 10

Gasoline ICE Hybrid 69 14 17 67 17 16

Diesel ICE 75 10 15 74 12 14

Diesel ICE Hybrid 70 10 20 70 11 19

Hydrogen FC 45 34 21 0 81 19

Hydrogen FC Hybrid 44 35 21 0 79 21

Gasoline FC 67 14 19 66 16 18

Gasoline FC Hybrid 66 14 20 65 16 19

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)

Implementation

Stage

Gasoline DI

Spark-

Ignition

Boosted

Downsized

Engine

High Speed DI

Diesel with

Particulate

Trap, NOx

Catalyst

Gasoline SI

Engine/

Battery-Motor

Hybrid

Fuel Cell

Vehicle

On board

Hydrogen

Storage

Market competitive

vehicle1

~ 3 years ~ 3 years ~ 3 years ~ 10 – 15 years2a

Penetration across

new vehicle

production3

~ 10 years ~ 10 – 15 years ~ 15 years ~ 25 years2b

Major fleet

penetration4

~ 10 years ~ 10 – 15 years ~ 10 – 15 years ~ 20 years2c

Total time required ~ 20 years ~ 25 years ~ 30 years ~ 50 years

Earliest year of

significant impact

2025 2030 2035 2050

05/07/04