• Performance model• Mass →Power demand model → Acceleration energy and

total energy loss → Gas-equivalent fuel economy• Sensitivity of gas-equivalent fuel economy with respect to

vehicle mass

Optimal Design of Fuel Cell Vehicle and Impact of Public Policy on CO2 Emission

Future Work

Acknowledgements

Project Objectives• Create a method to optimize fuel cell vehicle (FCV) design

incorporating uncertainty of exogenous variables such as public policy and gasoline price

• Investigate the effects of public policy on FCV design and CO2 emission in transportation sector

Student: Swithin Samuel RazuDepartment of Mechanical and Aerospace Engineering

Faculty Advisors: Dr. Shun Takai Dr. Ming C. Leu

Department of Mechanical and Aerospace Engineering

• Vehicle emissions account for up to 95% of city CO2 emissions creating smog, climate change, health risks and damage agricultural infrastructure

• U.S government requires automobile manufacturers to meet Corporate Average Fuel Economy (CAFE) standards of 35.5 mpg by 2016 and 54.5 mpg by 2025 and emission targets of 250 g CO2/mile by 2016 and 163 g CO2/mile by 2025

Background

42.5%

HYDROGEN

INPUT

2.22 MJ

FC LOSSES

FUEL

CEL

L SY

STEM

REGENERATIVEBRAKING

ACCESSORIES

BRAKING

0.57 MJ

ENERGY

LOSSDRIVE-TRAIN

ACCELERATION

1.4 MJ1.1 MJ

7.8%

1%

VEHICLE

DR

IVE-

TRA

IN

BATTERY

AND BATTERY LOSSDC/DC CONVERTOR

POWER BUS LOSS GENERATOR LOSS

17%

5% 33%

35%

LOSS

DC/DC

ELECTRIC ENERGY

FC OUTPUTP

OW

ER B

US

1.27 MJREGENERATIVE

0.34 MJTOTAL

1.62 MJ

40

50

60

70

80

90

100

900 1000 1100 1200 1300 1400 1500 1600 1700 1800 1900

MP

G

Vehile mass (Kg)

Vehicle mass Vs Fuel economy (NYCC)

Honda Clarity

$4/gal. $5/gal.Aggregate $2/gal. $3/gal.

90 MPG

60 MPG

0

0.2

0.4

0.6

0.8

1

$10,000 $20,000 $30,000 $40,000

Dem

and

Price of Fuel Cell Vehicle

GV HV EV FCV

0

0.2

0.4

0.6

0.8

1

$10,000 $20,000 $30,000 $40,000

Dem

and

Price of Fuel Cell Vehicle

GV HV EV FCV

0

0.2

0.4

0.6

0.8

1

$10,000 $20,000 $30,000 $40,000

Dem

and

Price of Fuel Cell Vehicle

GV HV EV FCV

0

0.2

0.4

0.6

0.8

1

$10,000 $20,000 $30,000 $40,000

Dem

and

Price of Fuel Cell Vehicle

GV HV EV FCV

0

0.2

0.4

0.6

0.8

1

$10,000 $20,000 $30,000 $40,000

Dem

and

Price of Fuel Cell Vehicle

GV HV EV FCV

0

0.2

0.4

0.6

0.8

1

$10,000 $20,000 $30,000 $40,000

Dem

and

Price of Fuel Cell Vehicle

GV HV EV FCV

0

0.2

0.4

0.6

0.8

1

$10,000 $20,000 $30,000 $40,000

Dem

and

Price of Fuel Cell Vehicle

GV HV EV FCV

0

0.2

0.4

0.6

0.8

1

$10,000 $20,000 $30,000 $40,000

Dem

and

Price of Fuel Cell Vehicle

GV HV EV FCV

0

0.2

0.4

0.6

0.8

1

$10,000 $20,000 $30,000 $40,000

Dem

and

Price of Fuel Cell Vehicle

GV HV EV FCV

0

0.2

0.4

0.6

0.8

1

$10,000 $20,000 $30,000 $40,000

Dem

and

Price of Fuel Cell Vehicle

GV HV EV FCV

• Step 2: Vehicle performance model for fuel economy• Gasoline equivalent fuel economy (

= Energy content of gasoline = Gasoline density = Total distance covered in the NYCC cycle = Acceleration energy Total energy loss

• Acceleration energy (

• is obtained from the vehicle model • Total energy loss ()

• FCV sub-system models

Deceleration power demand [

Acceleration power demand [

Current Progress

• The FCV vehicle mass needs to be reduces by 26% to increase the FE from 60 to 90 gas-equivalent mpg

Approach• Focus on two FCV performance variables that impact

demand: Fuel economy and 0-60 mph acceleration• Decompose FCV to four sub-systems: Fuel cell, Battery,

Motor, and Power demand

• Step1: Create market model relating performance variables and profit

• Step 2: Create FCV performance model and FCV sub-system models relating design variables and FCV performance variables

• Step 3: Optimize design variables such that FCV profit is maximized

• Step1: Market model

Profit = (Price – Unit Product Cost) x Units Sold = (Price – Unit Product Cost) x Market Size x Market Share

Unit Product Cost Conditioned on FCV DesignMarket Share Conditioned on FCV Design, Price, Customer

preference and Fuel Price

• Complete linking performance variables to design variables• Optimize design variables to maximize profit• Incorporate vehicle cost and CO2 emissions into the market

model• Model acceleration as a performance variable• Integrate dynamic competition between other alternative

fuelled vehicles

• This research is supported by the Intelligent System Center at the Missouri University of Science and Technology

Exogeneous variables

-Form-Tech-Specs-Emissions

Profit

Market size

Price Revenue

Cost

Market share

Unit sold

FCV design

Product cost

Regulation Policy

Customer survey

Customer preference

Gasoline Price

Fuel Cell

DC/DC Battery

Motor

Po

wer

Dem

and

Power Demand Model

Design Variables

Vehicle Parameters

Battery Model

Design Variable

Battery Parameters

Fuel Cell Model

Design variables

Fuel Cell Parameters

Motor Model

Design Variable

Motor Parameters

• Market model• Data: Choice survey result comparing gasoline, hybrid,

electric and fuel cell vehicle (GV, HV, EV, FCV)• Result: Choice probability (demand) of GV, HV, EV, FCV as

a function of FCV price, FCV fuel economy, gasoline price, government subsidy, and availability of fuel stations

• For lower gasoline prices ($2,3/gal), the FCV demand is sensitive to FCV price and for higher gasoline prices ($4,5/gal), the FCV demand is less sensitive to FCV price

• Increased fuel economy (60mpg to 90mpg) can compensate for higher FCV price• At FCV price of $20,000 demand increases from 58.6% to

68.9%• At FCV price of $30,000 demand increases from 24% to

33%