Renewable NH3 and Direct NH3 Fuel Cells: Canadian R&D for Clean

Distributed Electricity Generation Presented at

9th Annual NH3 Fuel Conference San Antonio, TX

Andrew McFarlan, Ph.D.

October 1 2012

CanmetENERGY is the R&D branch of Natural Resources Canada, with headquarters and labs in Ottawa ON, and labs in Varennes QC and Devon AB

Ottawa, ON

Devon, AB

Varennes, QC

Introduction Anhydrous ammonia (NH3), the chemical building block for nitrogen fertilizers, is also a carbon-free fuel. Considerable infrastructure is in place to transport and store NH3 due to its extensive use in agriculture. Direct NH3 fuel cells can potentially produce electric power and high grade heat (CHP) efficiently and with zero emissions Like hydrogen, NH3 can be produced from non-fossil renewable electricity sources (hydro, wind). NH3 production from renewable electricity, and NH3 as a renewable fuel is gaining attention worldwide, particularly in the Corn Belt of US Midwest.

Topics:

Conventional NH3 production – energy requirements and GHG emissions Direct NH3 fuel cell development at

CanmetENERGY Direct fuelling of conventional SOFC’s

with NH3 NH3 as a carbon-free renewable fuel R&D needs and opportunities

5

Conventional (Fossil) NH3 Production ~200 million tonnes global capacity annually Production: 67% natural gas-based, 27% coal-based Use: >80% NH3 is used for fertilizer manufacture US imports >50% of its NH3 Canada exports ~50% of its NG to US

Also, NH3 Production from NG or coal produces pure

CO2 byproduct which lowers cost of large scale CCS – and can be used for enhanced recovery of oil or coal-bed methane (NH3 from coal with CCS practiced commercially in Beulah N.Dakota since 2000)

NH3 Production from Natural Gas Reforming

Energy input: 30 million scf NG per tonne NH3 (30 GJ/tonne NH3) CO2 Emissions: 1.8 tonnes CO2 per tonne NH3

Overall Efficiency and CO2 Emissions During Production and Distribution of Hydrogen Energy Carriers

• CO2 capture and sequestration contributes only slightly to the losses in the full hydrogen value chain

• Central hydrogen and ammonia production seem to be the most efficient way to produce CO2-free energy carriers

• Ammonia infrastructure development is easier because truck transport is possible – supply and demand will be in balance through time

• On site natural gas reforming and methanol steam reforming have highest CO2 emissions

(H. Anderson, World Hydrogen Energy Conference, Montreal, 2002) Conclusions drawn from studies done by Norsk Hydro:

Direct NH3 Fuel Cells:

Development of Proton-Conducting Ceramic FC Materials

at CanmetENERGY

What is the concept? • Ammonia is catalytically decomposed

to N2 + H2 at anode • high temperature, low pressure favors

equilibrium limited decomposition • Protons transport across a solid proton

conducting electrolyte. • Removal of hydrogen at the anode

drives decomposition reaction to completion.

• H2/air oxidation at the cathode provides chemical driving force for the fuel cell AND provides the heat of reaction for ammonia decomposition.

• Products of the fuel cell are nitrogen, water, electric power and heat.

Air/Oxygen

Load

H+

H+

H+

H+ H2O

2NH3 N2 + 3H2

N2

3/2 O2

Anode Cathode

Electrolyte Fuel

3H2 6H+ + 6e-

6e-

3O2- 3/2 O2 + 6e-

3H2O 6H+ + 3O2-

N2 + 3H2O 2NH3 + 3/2O2 Overall:

Direct NH3 Fuel Cells:

Cell performance as a function of Pr concentration (700°C).

Optimization at approximately Pr – 0.05 (BaCe0.8Gd0.15Pr0.05).

Related to increased material density and decrease of cell unit volume.

0

10

20

30

40

50

60

70

80

90

0.00 0.02 0.04 0.06 0.08 0.10 0.12Pr content

Opt

imal

Pow

er D

ensi

ty (m

W/c

m2 ) Hydrogen

Ammonia

BCG

First BCGP

Optimal Pr

Fuel Cells, volume 7, issue 4 (2007) 323.

Pt/BCGP/Pt Ammonia Single Cell Fuel Cell

Direct NH3 Fuel Cells:

Mixed ionic and electronic conducting anode

0

5

10

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0 20 40 60 80 100 120 140Current Density (mA/cm2)

Pow

er D

ensi

ty (m

W/c

m2 )

Pt anodeNiO-BCE anode

0.0

0.1

0.2

0.3

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0 100 200 300 400 500 600Time on stream (h)

Volta

ge (V

)

Single cell operating at:100 mA and 46 mW

NiO-BCE anode outperformed Pt anode in a BCGP electrolyte supported fuel cell at 600°C in NH3

Cell was stable for over 500 h on ammonia fuel with very little degradation in performance.

Direct NH3 Fuel Cells:

•Proton conducting ceramics allow lower operating temperatures in H2 and NH3 •They are thermodynamically more efficient than oxygen ion conducting ceramics •X-section of Samarium doped barium cerate (BCS) under scanning electron microscope shows a uniform and dense ~25 micron thickness electrolyte layer, supported by a porous 1 mm thickness anode composed of NiO-BCS cermet •This single fuel cell exhibits correct material properties needed for producing a fuel cell stack.

In-house development of advanced proton conducting ceramic fuel cell electrode/electrolyte materials:

Direct NH3 Fuel Cells

Direct NH3 Fuel Cells:

Testing NH3 on Conventional Precommercial SOFC Stacks at

Acumentrics Canada

Acumentrics Canadian Division was established in 2007 at the Fuel Cell Research Centre in Kingston ON. CanmetENERGY partnered with them to do field testing of their stack using direct NH3 fuel.

RP-20 500W SOFC systems at a well head in Texas (2012)

Source: www.acumentrics.com

Direct NH3 Fuel Cells: Acumentrics SOFC Direct NH3 Field Test Assess the technical feasibility of

using ammonia as a direct fuel source in a SOFC micro CHP generator.

Measure the long term stability and performance of the SOFC to see if the stack materials are degraded by direct NH3 fuel.

Measure level of emissions, especially NOx in the stack effluent gas

Determine the modifications required to a natural gas based system to allow it to operate on ammonia

Objectives:

Acumentrics SOFC stack: • 9x5 array of extruded tubes • NiO/YSZ anode support • YSZ electrolyte • shell (air) side cathode • nominal 1 kW output

Stack/Hot Box

RecuperatorStartup Burner

Anode Inlet

Power Leads

Thermocouple/Voltage Sense Leads

Stack/Hot Box

RecuperatorStartup Burner

Anode Inlet

Power Leads

Thermocouple/Voltage Sense Leads

Direct NH3 Fuel Cells: Acumentrics Custom SOFC Test Stand

Stack

Test Stand

Fuel Cell Module

Temperature profile for CPOX Polarization Curve

Direct NH3 Fuel Cells: Acumentrics SOFC Stack Under Test

CPOX Polarization DataCurrent and Stack Temps During Test

Average Stack Temp = 785 deg C

700

720

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760

780

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820

840

860

10/12/200814:09

10/12/200814:12

10/12/200814:15

10/12/200814:18

10/12/200814:21

10/12/200814:24

10/12/200814:26

10/12/200814:29

Date/Time

Stac

k C

urre

nt

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Stac

k C

urre

nt (A

mps

) 9 T206 Stack Bottom A 10 T207 Stack Bottom B 11 T208 Stack Bottom C 12 T209 Stack Middle A 13 T210 Stack Middle B 16 T213 Stack Top B 17 T214 Stack Top CAvg. Stack Temp Stack Amps

Tem

pera

ture

°C

NH3 Polarization DataCurrent and Temperatures During Test

Average Stack Temp = 835 deg C

700

720

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840

860

08/01/200913:13

08/01/200913:14

08/01/200913:16

08/01/200913:17

08/01/200913:19

08/01/200913:20

08/01/200913:22

Date/Time

Stac

k Te

mpe

ratu

res

(deg

C)

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9 T206 Stack Bottom A 10 T207 Stack Bottom B 11 T208 Stack Bottom C 12 T209 Stack Middle A 13 T210 Stack Middle B 16 T213 Stack Top B 17 T214 Stack Top CAvg Stack Temp Stack Amps

Temperature profile for NH3 Polarization Curve

Direct NH3 Fuel Cells: Acumentrics SOFC Stack Under Test

NH3 Polarization Curve

Direct NH3 Fuel Cells: Acumentrics SOFC Stack Under Test

y = -0.00145x + 1.01483R2 = 0.99876

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0.55

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0.65

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0 20 40 60 80 100 120 140 160 180 200

Current Density (mA/cm^2)

Volts

/Cel

l (VD

C) V1

V2V3V4V5VavgLinear (Vavg)

Direct NH3 Fuel Cells: Acumentrics SOFC Stack Under Test

CPOX (Natural Gas) Operation @20A

CPOX Stack Temperatures @20AAverage Delta T = 131C (Top to Bottom)

650

675

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850

12:12 12:14 12:15 12:17 12:18 12:20 12:21 12:23 12:24 12:25

Date/Time

Stac

k Te

mpe

ratu

res

(deg

C)

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9 T206 Stack Bottom A 10 T207 Stack Bottom B 11 T208 Stack Bottom C 12 T209 Stack Middle A 13 T210 Stack Middle B 16 T213 Stack Top B 17 T214 Stack Top CAvg. Stack Temp Stack Amps

Direct NH3 Fuel Cells: Acumentrics SOFC Stack Under Test

NH3 Stack Temperatures @ 20 AmpsAverage Delta T = 63C (Top to Bottom)

650

675

700

725

750

775

800

825

850

18:59 19:00 19:01 19:03 19:04 19:06 19:07 19:09 19:10 19:12 19:13 19:14

Time

Stac

k Te

mpe

ratu

res

0

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9 T206 Stack Bottom A10 T207 Stack Bottom B11 T208 Stack Bottom C12 T209 Stack Middle A13 T210 Stack Middle B16 T213 Stack Top BAvg Stack Temp Stack Amps

NH3 Operation @20A

Direct NH3 Fuel Cells: Acumentrics NH3 SOFC Field Test

Long term operation (~1400h) showed no adverse effects or drop off in stack performance for conventional SOFC.

No residual NH3, or NOx was detected in the stack effluent gas, or effectively zero emissions operating on ammonia.

NH3 performance surpasses natural gas due to lower stack temperature gradient

There is potential to simplify the system design considerably by using NH3, lowering cost to build the system

Independently in 2010, Topsoe Fuel Cells (Denmark) presented similar findings using their near commercial SOFC’s

Knowledge Gained:

Production and Use of Renewable “Green” NH3

NextHydrogen Study

NEXT HYDROGEN Economical Clean Hydrogen, at Scale Innovation in Water

Electrolysis™

NEXTHydrogen is a Canadian clean technology company who is developing MW scale electrolyzers as well as “green” applications of this technology

Renewable NH3 (by water electrloysis, air separation, Haber Bosch synthesis) from low cost hydroelectricity ($0.02/kWh -$0.35/kWh) can be competitive with fossil NH3 in the near future. Windfarms with low installed costs and good to very good wind availability may also compete.

Renewable (green) NH3 addresses energy security – for both energy and food production by reducing the industry’s dependency on Canada’s NG, heavy oil and coal resources.

Green NH3 is an emerging decentralized (off grid) energy resource. It has the potential to reduce the GHG emissions related to fossil NH3 production.

Demonstration ready technologies for using green NH3 as a fuel are available today. They include NH3 in internal combustion engines, and solid oxide fuel cell combined heat and power systems. NH3 production technology based on electrolysis is also at demo stage of development.

Canadian Opportunity for “Green” NH3: NextHydrogen Study

Economics of Natural Gas and Coal Based NH3 Production

0100200300400500600700800900

1000

0 5 10 15 20

NG Cost $/MMBtu

NH3

Cost

$/to

nne

NGNG + $30/tonne CO2

0100200300400500600700800900

1000

0 50 100 150Coal Cost $/tonne

NH3

Cost

$/to

nne

Coal

Coal + 30$//tonne CO2

Fig.1 and Fig. 2 show that low-cost NG and/or coal based NH3 production remain economical for large scale production. Carbon Capture adds incrementally to production cost, more so for coal than NG.

Fig.1 Fig.2

Economics of “Green NH3”

Fig. 3 shows that renewable NH3 from low cost hydroelectricity ($0.02-$0.35 /kWh) can be competitive with fossil NH3 in the near future. Hydrogen costing $1.50-$2.50 /Kg from wind energy will also be competitive.

Fig.3

0100200300400500600700800900

1000

0.00 1.00 2.00 3.00 4.00

Hydro, cents/kWh; Hydrogen, $/Kg

NH3

Cost

$/to

nne

HydroelectricityHydrogen

Economics of “Green NH3”

Fig. 4 shows the strong influence of wind farm installed cost and wind capacity factor (CP) on renewable NH3 cost. Wind farms require an installed cost approaching ~1000/kW, good wind (CP=0.35) or even very good wind (CP=0.45) to be competitive in today’s NH3 market.

Fig.4

0100200300400500600700800900

1000

0 1000 2000 3000 4000

Windfarm Cost $/KW

NH

3 C

ost $

/tonn

e CP=0.45CP=0.35

Pursue renewable NH3 production and technology demonstration tailored to match economic advantages of a given region.

Pursue new applications for green NH3, e.g. farm vehicles, SOFC for CHP and refrigeration in regions where existing NH3 infrastructure can be leveraged.

Pursue R&D on proton conducting ceramic electrolyte materials for efficient solid state electrochemical synthesis of ammonia.

Nurture emerging Canadian expertise and technology development in related areas, and strengthen linkages nationally and internationally with entities having similar interests.

R&D to advance biomass gasification for green NH3

Next Steps

Potential for Green NH3 Production From Biomass Gasification ENERKEM (right) and NEXTERRA (below) are two Canadian companies who are developing syngas technologies based on biomass residues and MSW. These syngas processes could be utilized to produce liquid fuels, RNG, and green ammonia.

“Green” NH3 – An option for distributed clean energy and distributed NH3 production in Canada ?

Thank You

Contact information: Andrew McFarlan, Ph.D. Manager, Bioenergy R&D Natural Resources Canada CanmetENERGY, 1 Haanel Dr. Ottawa K1A 1M1 Ph: 613-995-2376 E-mail: andrew.mcfarlan@nrcan.gc.ca

Acknowledgements: Nicola Maffei, Ph.D., CanmetENERGY Luc Pelletier, formerly CanmetENERGY now at Health Canada