Nature Of Hydrogen Demand for Fuel Cells

And NMRL’s Experience on Onsite Hydrogen Generation

S Roy Choudhury, J. RangarajanNaval Materials Research Laboratory, Ambernath-421506

Hydrogen Provision

• Distributed hydrogen retail outlets for mobile / stationary applications– Compressed H2 transport by pipelines like

CNG network– Onsite H2 generation from other feed stocks

• Coal• Hydrocarbons• Alcohols• Ammonia

Hydrogen Provision

• Online/onboard hydrogen generation for mobile systems – Reforming /cracking of hydrocarbon feed

stocks– Reforming/cracking of alcohols– Other inorganic/organic feed stocks

Ammonia cracking

Hydride hydrolysis/cracking

H2 quality

Impurity tolerance increases with increase in operating temperature of fuel cells

Low temperature acid FCs

Phosphoric acid fuel cell• Operates at 130-

2000C• CO tolerance < 2%• S and Cl in ppm level

Polymer electrolyte fuel cells

• Operates at 60-800C• CO tolerance in ppm

level• S & Cl in ppm level

Limits the primary source of fuel

Low temperature alkaline FCs

• Operates around 120-1700C• High CO tolerance

• CO2 tolerance in ppm level

• Cl and S in ppm level

Difficult for terrestrial application

High temperature FCs

Solid Oxide FCs

• Can take CO as fuel

• S & Cl in ppm level

Molten Carbonate FCs

• Can take high CO

• S & Cl in ppm level

The Key issuesThe Fuel Quality

Fuel cells are advanced power generation devices

requires quality feedstock, free from sulfur

The oil refineries have to provide uniform low sulfur fuels.

The Fuel Quality

Fuel cells are advanced power generation devices

requires quality feedstock, free from sulfur

The oil refineries have to provide uniform low sulfur fuels.

The Key issues

The conversion Devices

High cost for CO removal – PEMFC

Low reformer cost – PAFC, SOFC, MCFC

Compact thermal systems to realize mini converters

The conversion Devices

High cost for CO removal – PEMFC

Low reformer cost – PAFC, SOFC, MCFC

Compact thermal systems to realize mini converters

Fuel cell program in NMRL

Fuel cellOur mission

To develop totally indigenous fuel cell for Indian armed forces & commercial use

All necessary subsystems like fuel processor, startup systems etc.

Spin off benefits

Achievements so far …

Catalyst Electrode Acid holder

matrix Graphite gas

distributor plate

Acid management systems

Humidifiers Thermal systems Power conditioners

Online hydrogen generation devicesHydrogen filter systems

Prototypes :- Fuel cell based power packs with all accessories

NMRL’s View

Onsite hydrogen generation is the way to introduce Fuel Cells successfully

• For mobile application – supply purified H2 from onsite local generation center – PEMFCs, PAFCs

• For stationary application – build onsite H2 generation plant – PAFCs, SOFC

NMRL’s experience in onsite hydrogen generation for fuel

cells

Generation of H2 for possible fuel cell applications

From organic feed stocks

From inorganic feed stocks

Alcohols Hydrocarbons

methanol

ethanol

CNG LPG Naptha, diesel etc.

NH3

Hydrazine

NMRL’s interest

Bio H2 using algae

storage of H2 for possible fuel cell applications

Compressed gas Metal hydrideNaAlH4 etc.

Occluded H2C SWNT, Organo-metallic

framework etc.

Chemical hydrides

Low temperature

storage

High pressure light weight

storage

NaBH4 , CaH2

NMRL’s interest

H2 Content & requirement

Material H2 wt % H2 lit/lit @NTP

CH3OH 18.75 5250

CNG 50.00 8

CaH2 9.52 2133**

NaBH4 21.05 4715**

Comp H2

@200atm

100.00 200

** considering powder density=1

1 kWatt power H2 consumption

(lpm @ NTP)

At 100 % efficiency

5.88

At ~65% efficiency (~0.6V cell pot)

9.04

At ~65% efficiency (~0.6V cell pot)

With 70% utilization

13

Hydrogen generation devices

Reformers Online generation of

hydrogen by methanol reforming

Various configurations, for 2lpm (100W), 80 lpm (5kW),900 lpm (60kW) power packs

Output CO level <0.5%

Hydrogen crackers One shot use Suitable for subwatt to 100

watt systems Different options:-

super-corroding alloy /Calcium hydride hydrolysis

NaBH4 in caustic base solution – catalyst induced hydrolysis

Pilot methanol reformer – 8-10 lpm hydrogen output for process design and scale up studies (1997)

Compact reformer 1999 (80 lpm hydrogen)

Bukhari reformer 2003

2-5 lpm of hydrogen

Instrument free, very compact, zero powered / rotating device

Evolution of methanol

reformer at NMRL

Evolution of methanol

reformer at NMRL

High capacity methanol reformer , 50nM3/hr –2003 hydrogen, suitable to ~60kW PAFC power pack

Process design of reformer – NMRL

Detail engineering, control systems and installation – Xytel India

Commissioning - NMRL

Evolution of methanol

reformer at NMRL

Evolution of methanol

reformer at NMRL

Hydrogen generator for small fuel cells

Liquid phase refillable cracker-NaBH4 in caustic •Catalytic (Pt on IRA-100 resin) hydrolysis•Capacity 0-2watt•Protable, orientation free usage,•Floating type

Super corroding alloy, one shot cartridge• Capacity 5-25 watt•Controlled water hydrolysis

CaH2 based, one shot cartridge• Capacity 50-150 watt• Controlled water hydrolysis

Thermal systems• Snadwich type steam heater/cooler for

quick pre-heating and heat removing of PAFC stacks

Bayonet type forced methanol based catalytic heater for compact reformer

Capillary action based natural methanol catlytic burner

Bayonet type natural & fan based hydrogen heater Cartridge type humidifier with hydrogen heater

NMRL’s Fuel Cells – Products available for commercial usage

700-1000 watt PAFC based UPS / generator with built in compact methanol reformer

Delivers 220V AC, 700-1000VA PAFC battery (35 Kg) Nova-1 / 2

Nominal power of 1000 watt

100 watt self contained power pack

•Output :- 12+0.05 V DC upto 100 watt (max)•Size 52x27x25 cm (12Kg)•Hydrogen source by hydride cracking•Hydrogen source by compact catalytic burner based reformer

Conclusion

• Hydrogen source, generation methodology & fuel cell type – critical for successful application

• Available supply infrastructure can be catered for hydrogen application

– This is possible through onsite hydrogen generation

Generally Hydrogen is produced in industry at the expense of utility

For fuel cell application utility is generated at the expense of

hydrogen