Solid Oxide Fuel Cell Development at Topsoe Fuel Cell A/S

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Solid Oxide Fuel Cell Development at

Topsoe Fuel Cell A/S

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Briefly on Topsoe Fuel Cell

Fuel

Fuel _componentsMaterials & Fuel_cell stack Fuel cell device End use End

use maintenance_maintenanceService/ Service/

System Integrator

TOFC’s Position in the Value Chain

• Development, marketing and sales of SOFC technology • Founded in 2004

• Subsidiary of Haldor Topsøe A/S (wholly owned) • SOFC research & development since 1989

• Full time employees: 30 (January 2007) 50 (June 2007)

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SOFC Principles

Anode

Catode

Electrolyte

-½O

₂

+ 2e

-

_O

2-H

₂

+ O

2-

_H

2

O + 2e

-O 2-O

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Generic SOFC unit

Desulfur-ization reformerPre- Pre-heat

Filter/

blower Pre-heat

Fuel cell stack DC/AC converter Control CO₂ Water AC electricity Air Natural gas

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1989 – 1997: Electrolyte-supported cells • Operation temperature: 1000°C • Ceramic interconnect • 500 W HTAS/Risø stack (>500 h in 1996) 1997 – 2005: Anode-supported cells • Operation temperature: 700-850°C • Metallic interconnect • 100 W HTAS stack (>12000 h in 2004) • 1 kW+ HTAS stack (in 2003)

2003 and future: Metal-supported cells

• Operation temperature: 500-700°C

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Anode supported planar Cells

Single Cell Performance

375 m

Wide temperature operation window

1.2 1.1 1.0 1.6 0.9 1.2 0.8 0.8 0.7 0.4 0.6 _0.0 0.50 0.0 0.5 1.0 1.5

Current density [A/cm ]2

C el l v ol ta ge [ V] P ow er d en si ty [ W /c m ] 2 2.0 2.5 850°C 750°C 650°C > 1,5 W/cm2

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Manufacture of Anode-supported Cells

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Anode supported Cells

21 cm

24x24 cm2

12x12 cm2

22x50 cm2

Our largest cell to day: 22 x 50 cm2

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The Topsoe Stack Concept

Compact Multilayer Design

120 mm 120 mm

75 mm

75-Cell Stack (750-800

o

_C)

• 1 mm per repeatable unit

• 2.4 kW/liter at 0,38 A/cm

2

• 0,25 kW/ kg

• 60 V at 20A

12x12 cm2 0 0,5 1 1,5 2 2,5 3 3,5 4 4,5 5 0 2000 4000 6000 8000 10000 12000 14000 Hours V ol t

Five cell stack _{13000 hours +}

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Larger Cells: 18 x 18 cm

2

Stack durability

Cost / performance optimization Degradation at high power density

60 cells

18x18 cm

2

Co-flow

75 cells

12x12 cm

2 0 1 2 3 4 5 6 7 8 0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 Current [A] S ta ck V ol ta ge [ V ] 0 100 200 300 400 500 600 700 800 S ta ck P ow er [ W ] Stack Voltage Voltage at 75% F.U. Stack Power Power at 75% F.U. 0.55 W/cm2 0,7 A/cm2

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Flow geometry

Modelling and Experimental

600 650 700 750 800 850 600 650 700 750 800 850 600 650 700 750 800 850 Flow

design gradient Temp. (°°°°C/m) Temp. average (°°°°C) Power density (W/cm2) Counter-flow 2610 750 0.264 Cross- flow 4110 692 0.146 Co- flow 2360 728 0.218 Counter flow Cross flow Co flow

59 60 61 62 63 64 65 12 14 16 18 20 22 24 26 28 30 32 I (Amp) U (V )

75-Cell Stack

Natural Gas FU: 65% 1.8 kW Counter-flow

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Stack Modelling

Cross-flow, 18x18 cm2 _{foot print}

Large temperature gradient

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ceramic support metallic support

1000

o

_C

₈₅₀

o

_C

₇₀₀

o

_C

₆₀₀

o

_C

Improved reliability

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SOFC System

Development

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Product Requirements Comparison (2)

CHP

APU

S.U. time, min.

480 <20

Lifetime, hours

40000

10000

Efficiency (el),%

>45

>35

Maintenance, h

7000

1200

Cycles

50 5000

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SOFC System Modelling - 250 kW Base Case

Air Blower Catalytic Burner Air SOFC E 3 E 2 A no de C at ho de E 6 E1 E 5 Anode recycle Water for start

up Natural gas Flue Gas Desulphurisation Prereformer E7 Flue Gas Energy Flows (kJ/s) Natural Gas Case El Eff. % Cogen Eff % Base Case – NG Prereform

Stationary 55.5 83.6 Methanol APU application 53.3 84.6 DME APU application 53.0 82.5 Diesel CPO (O2/C = 0.35) 40.7 85.4

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Transient Part Load Cycle

HIL Test System – 1 kW stack

Max. el. eff.: 55%

Total load cycle el. eff.: 37 %

600 0.8 500 _0.6 300 400 0.4 200 0.2 100 0.0 0 60 120 Time [s] E le ct ric p ow er [ W ] E ffi ci en cy [ -] 180 240 0 P_demand P_gross P_net System efficiency

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TOFC Lightweight Hot Box – 1.8 kW

_el

Project for US Air Force

2 x 40 cells (12x12 cm

2

₎

Projected

• Weight

stack + manifold

5,7 kg

• Volume

stack + manifold

2 liters

• Operate on de-sulphurized JP-8/synthetic diesel • 1.5 kW nominal power over 500 hours

• 10 start up/shut down cycles

• Fuel utilization > 80% (nominal power) • System efficiency > 30%

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SOFC Projects supported by Danish Utilities

I) Stack hot box for micro CHP

II) 10 kW test and demo facility

H. C. Ørsted Power Plant / Copenhagen

Air Blower Catalytic Burner Air SOFC E 3 E 2 A no de C at ho d e E 6 E1 E 5 Anode recycle Water for start

up Natural gas Flue Gas Desulphurisation Prereformer E7 Flue Gas

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Carbon Formation - Graphite Data

200 300 400 500 600 700 800 900 1.00 1.25 1.50 1.75 2.00 2.25 2.50 2.75 3.00

O/C ratio

D eg . c

Carbon Formation Region

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Methanation of MeOH for SOFC

Electrical net efficiency = 53 % Electrical net efficiency = 53 % Co

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Carbon Formation - 250 nm Ni Crystals

200 300 400 500 600 700 800 900 0.5 0.75 1 1.25 1.5 1.75 2

O/C ratio

D eg

. C _{Carbon Formation Region} _{No Carbon}

Formation

Carbon whisker

Ni crystal

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TOFC / Wärtsilä Collaboration

Wärtsilä 25 kW -prototype with 24 TOFC Stacks

2006

20 kWe -prototype 2007 - 2008

20 – 50 kWe,

NG, methanol, bio gas 0 10 20 30 40 50 60 70 80 90 50,0 550,0 1050,0 1550,0 2050,0 2550,0 3050,0 Running Hours V ol ta ge [V ] a nd C ur re nt [A ] 0 50 100 150 200 250 300 C ur re nt D en si ty [m A /c m 2]

Average Stack Voltage Average Stack Current Average Current Density

Wärtsilä 5 kW test system

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Secure Channels to Market Diversification & Consolidation

! " #

#

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Conclusion

• New, up-scaled cell and stack manufacturing plant

• Start-up 2008

• Capacity:

• 150,000 – 250,000 cells

• 3,800 standard stacks

• > 4 MW

• Supported by EU with 4.8 m EUR

Standard production of 12x12 cm2 _stacks

18x18 cm2 _{co-flow stacks tested}