Fuel Cell APU for Commercial AircraftFuel Cell APU for Commercial Aircraft

Joe BreitSystems Concept Center

Boeing Commercial Airplanes(In Conjunction with NASA)

AgendaAgenda

• Background

• NASA

• SOFCo

• Integration Options

• Boeing

Turbine APU Engine

LargeAirplane (777-sized)

NOx Emissions atAirport

Replacing APU with fuel cell will reduce airport emissions

Replacing APU with fuel cell will reduce airport emissions

Fuel Cell

Boeing 777-sized “More Electric Airplane”

Future “More Electric Airplane” is ideally suited for fuel cell APU

Future “More Electric Airplane” is ideally suited for fuel cell APU

Present APU

Future 440 kW Fuel Cell APU Concept

EnvironmentControlSystem

Motor

EnvironmentControlSystem

Motor

Engine

GearLift

Motor

GearLift Motor

DC

AC

DC

AC Starter/Generator

Engine

Starter/Generator

Air

craf

tSy

stem

sA

ircr

aft

Syst

ems AC

DC

Battery

Working with fuel cell industry to obtain future SOFC performance

Working with fuel cell industry to obtain future SOFC performance

- Tech. U. of Munich (i.e. Europeans) 2-year SOFC APU design completed

- SOFCo 1st contract completed, 2nd contract issued

- US & Canadian National Labs- NASA Glenn Feasibility study to Boeing

- GE Contract issued

- University of California, IrvineSOFC model completed

- Delphi Contract issued

- UTRC NASA to issue contract

- Turbine Co. Future Contract?

- Fuel Cell Energy In discussions

AgendaAgenda

• Background

• NASA

• SOFCo

• Integration Options

• Boeing

Concept 440 kW Solid Oxide Fuel Cell in Boeing 777 Airplane Tail Cone

2015 AerospaceSame as industrial plus:• Weight & Size• Altitude Operation• Jet-A fuel• Safety• Vibration & shock

2003 Industrial

Industrial Solid Oxide Fuel Cell Installations

NASA to leverage SOFC R&D for aerospaceNASA to leverage SOFC R&D for aerospace

• Cost• Efficiency• Commercialization• Reliability

2003 2004 2005 2006 2007 2008 2009 2010

NASA/Boeing fuel cell APU timelineNASA/Boeing fuel cell APU timeline

Boeing Fuel Cell Powered AirplaneDemonstrator

NASA FC APUPhase I (feasibility)

NASA FC APUProposed Phase II (proof of concept)

Current 5kW SOFC

Power Current Electrical System

with 5kW unit Hybrid aircraft unit

development

NASA FC APUProposed Phase III (scaled demo)

Boe

ing

IR&

D

N

ASA

/Ind

ustr

y C

olla

bora

tion DOE SECA program

AgendaAgenda

• Background

• NASA

• SOFCo

• Integration Options

• Boeing

SOFCo 1st System Configuration SOFCo 1st System Configuration

Cabin Air

Cathode

Anode

405 kW

36 kW

Comp. TurbineStarter/Generator

JetFuel

Waterto

Filter

Exh.

OutsideAir

Reformer

Recuperator

TrimHeat

Exchanger

FuelHeater

SteamGenerator

SOFCo System Advantages SOFCo System Advantages

Cabin Air

Cathode

Anode

405 kW

36 kW

Comp. TurbineStarter/Generator

JetFuel

Waterto

Filter

Exh.

OutsideAir

Reformer

Recuperator

TrimHeat

Exchanger

FuelHeater

SteamGenerator

SOFC operates near ambient pressure for low vessel weight

Trim Hx for low thermal gradients

Simple, single-stage 2.5 PR impellers

SOFCo System DisadvantagesSOFCo System Disadvantages

Cabin Air

Cathode

Anode

405 kW

36 kW

Comp. TurbineStarter/Generator

JetFuel

Waterto

Filter

Exh.

OutsideAir

Reformer

Recuperator

TrimHeat

Exchanger

FuelHeater

SteamGenerator

Efficiency loss at low pressure

High cost for low weight, reliable recouperator

Waste sulfur results in acidic water, needs filter prior to steam generator

480kW cooling air needed … Yikes!

Gas doesn’t fully expand to atmospheric pressure – lost power potential

Fuel CellHot Box

Recuperator

ATR

TrimHXTurbo/Comp

Burner

ExhaustOut

SOFCo APU concept fits within tail coneSOFCo APU concept fits within tail cone

APU compartment firewall

777 APU Cavity(aft end of airplane)

Future 2015 Hybrid Solid Oxide Fuel Cell APU

SOFCo says airplane APU achievable but challenging

SOFCo says airplane APU achievable but challenging

Old 2002 Study New 2003 Study

• Pressure/Temperature stack optimization

• Desulfurization & water extraction schemes

• Fuel processing alternatives

• Single (440kW) vs. two (2 ea. 250kw) units?

• 2nd iteration to optimize system

• 0.45kW/kg system density almost met goals

• 58% efficiency

• Fits within space

• Fuel sulfur a problem

• Aspen model identified 1st configuration needs to change

Air In

DepletedAir Out

Stacks (4)

Depleted Fuel Manifolds

Fuel Supply Manifolds

Air In

DepletedAir Out

Stacks (4)

Depleted Fuel Manifolds

Fuel Supply Manifolds

Fuel Cell Hot Box

AgendaAgenda

• Background

• NASA

• SOFCo

• Integration Options

• Boeing

Integration into airplane affects performance Integration into airplane affects performance

Exhaust Cabin airHybrid SOFC Fuel Cell

APU

Airplanetail cone

Option “A”(basic design with POX)

Option #Fuel eff.WeightDragThrust

A

#1 = Best Rating Fuel in

Sulfur Tolerant

Poorest Fuel Efficiency

3

LowestSystemWeight

1

No Drag Impact1

Best ThrustRecovery

1

Integration into airplane affects performance Integration into airplane affects performance

HeatExchanger

Hybrid SOFC Fuel Cell

APU

CathodeExhaust

H20

Cabin air

Anode Exh.

Option #Fuel eff.WeightDragThrustWater

A31113

#1 = Best

B Option “B”(recovers water and has ATR)

Fuel in

Lowest Sulfur

Fuel Req.

2

HighestUnit

Weight

3

High InletDrag3

LowestThrust

3

Recovers H2O to offset weight

1

Integration into airplane affects performance Integration into airplane affects performance

Separator

Hybrid SOFC Fuel Cell

APU

CathodeExhaust Cabin air

Anode Exh.

Fuel in

A31113

#1 = Best

CB23331

Option “C”(recycles water)

H2 & H20

Low Sulfur

Fuel Req. Air, N2, Sulfur, CO2

Option #Fuel eff.WeightDragThrustWater

Best Fuel Efficiency

12

Low Drag122

FuelSavedA

irpla

ne F

uel S

avin

gs

A B CDesign

Trading-Off: Weight, Drag, Thrust & Efficiency

Best Airplane Performance

Design “C” has best airplane value due to lowest drag & highest efficiency

Design “C” has best airplane value due to lowest drag & highest efficiency

Syst

em E

ffici

ency

(%)

Syst

em E

ffici

ency

(%)APU Fuel Efficiency

0.20

0.30

0.40

0.50

0.60

0.70

AgendaAgenda

• Background

• NASA

• SOFCo

• Integration Options

• Boeing

Future 2015SOFC APU

≈75% Efficient(Overall system at cruise)

0.6 litre

=Jet-A

40% less fuel used

40-45% Efficient(Jet-A to electrical

during cruise)

Jet-A

1 litre

=

In-flight fuel saving opportunityIn-flight fuel saving opportunity

Fuel saving opportunity on the ground is very attractive

Fuel saving opportunity on the ground is very attractive

Future 2015SOFC APU

60% Efficient(at std. sea-level conditions)

0.25 litre

=Jet-A

75% less fuel used

15% Efficient(over average operating cycle)

Typical Turbine-powered APU

Jet-A

1 litre

=

?

Cost Pollution(at altitude)

Power Output

DLD

02-3

1

Startup time0

100

200

300

400

500

Fuel

Cel

l Per

form

ance

(% o

f tur

bine

) 4000

Weight Fuel efficiency

Cruise

Ground

Overall, FCAPU looks to be beneficialOverall, FCAPU looks to be beneficial

Turbine APU Baseline

Top 4 aerospace SOFC APU challengesTop 4 aerospace SOFC APU challenges

• Technology ready by 2010 (enables a 2015 entry into service date)

• High system power density (0.5 kW/kg system goal)

• Ability to reform Jet-A fuel (1,000 PPM fuel sulfur level tolerance goal)

• 40,000 hour life in airplane environment

Forever New FrontiersForever New Frontiers