Nature Of Hydrogen Demand for Fuel Cells And NMRLs Experience on Onsite Hydrogen Generation S Roy Choudhury, J. Rangarajan Naval Materials Research Laboratory, Ambernath

Hydrogen Provision Distributed hydrogen retail outlets for mobile / stationary applications –Compressed H 2 transport by pipelines like CNG network –Onsite H 2 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

H 2 quality Impurity tolerance increases with increase in operating temperature of fuel cells

Low temperature acid FCs Phosphoric acid fuel cell Operates at C CO tolerance < 2% S and Cl in ppm level Polymer electrolyte fuel cells Operates at C CO tolerance in ppm level S & Cl in ppm level Limits the primary source of fuel

Low temperature alkaline FCs Operates around C High CO tolerance CO 2 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 issues 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 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 cell Our 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 devices Hydrogen filter systems Prototypes :- Fuel cell based power packs with all accessories

NMRLs View Onsite hydrogen generation is the way to introduce Fuel Cells successfully For mobile application – supply purified H 2 from onsite local generation center – PEMFCs, PAFCs For stationary application – build onsite H 2 generation plant – PAFCs, SOFC

NMRLs experience in onsite hydrogen generation for fuel cells

Generation of H 2 for possible fuel cell applications From organic feed stocks From inorganic feed stocks AlcoholsHydrocarbons methanol ethanol CNG LPG Naptha, diesel etc. NH 3 Hydrazine NMRLs interest Bio H2 using algae

storage of H 2 for possible fuel cell applications Compressed gasMetal hydride NaAlH 4 etc. Occluded H2 C SWNT, Organo- metallic framework etc. Chemical hydrides Low temperature storage High pressure light weight storage NaBH 4, CaH 2 NMRLs interest

H 2 Content & requirement MaterialH 2 wt %H 2 CH 3 OH CNG CaH ** NaBH ** Comp H ** considering powder density=1 1 kWatt powerH 2 consumption 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 NaBH 4 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 lpm of hydrogen Instrument free, very compact, zero powered / rotating device Evolution of methanol reformer at NMRL

High capacity methanol reformer, 50nM 3 /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

Hydrogen generator for small fuel cells Liquid phase refillable cracker-NaBH 4 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 CaH 2 based, one shot cartridge Capacity 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

NMRLs Fuel Cells – Products available for commercial usage watt PAFC based UPS / generator with built in compact methanol reformer Delivers 220V AC, VA PAFC battery (35 Kg) Nova-1 / 2 Nominal power of 1000 watt 100 watt self contained power pack Output : 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