Cutting Carbon Emissions with Polymer Electrolyte Membrane ... · •Zero-carbon or net-zero carbon...

Cutting Carbon Emissions with Polymer Electrolyte Membrane Fuel Cells

M.A.Sc, Mechanical Engineering

Research AssistantThermofluids for Energy and Advanced Materials (TEAM) LaboratoryDepartment of Mechanical and Industrial Engineering Faculty of Applied Science & EngineeringInstitute for Sustainable EnergyUniversity of Toronto

Nov 29, 2017

Daniel Muirhead

Thermofluids for Energy and Advanced Materials Laboratory

Outline

• CO2 emissions in transportation sector

• Electrifying mobile power applications

• Hydrogen as an energy carrier

• Fuel cell background

• Fuel cell market penetration (forklifts, hydrail and hydrogen buses)

• PGM cost challenge

• Research: improving PGM catalyst utilization

Daniel Muirhead ([email protected]) 2


Greenhouse gas emissions by sector (Canada)

• Transportation sector responsible for 24% of GHG emissions in Canada

• 23% of global energy-related GHG emissions from transportation sector (IEA Global EV outlook, 2017)

• 95% of transportation energy derived from liquid fuels


Source: Environment and Climate Change Canada (2017), National Inventory Report 1990-2015: Greenhouse Gas Sources and Sinks in Canadahttps://www.canada.ca/en/environment-climate-change/services/environmental-indicators/greenhouse-gas-emissions/canadian-economic-sector.html

https://www.canada.ca/en/environment-climate-change/services/environmental-indicators/greenhouse-gas-emissions/canadian-economic-sector.html


Reducing CO2 emissions in transportation and mobile power applications

• Requires high density stored energy or continuous electrical supply (catenary rail)• Zero-carbon or net-zero carbon fuels (e.g. Biofuels) or electrification

• Electrification can be achieved with batteries or fuel cells• Li-ion battery: energy carrier permanently encased in battery

• In fuel cell: energy carrier is a fuel stored externally, supplied continuously to electrode (i.e. hydrogen gas)


Toyota Mirai (https://ssl.toyota.com/mirai/fcv.html) Nissan Leaf (nissan.ca)Alstom Coradia iLint (alstom.com/press-centre)


Caveat: Carbon intensity of electrical production

• Electrification of transport GHG reduction only if electrical generation is low-carbon

• Ontario, Quebec, BC, Manitoba, Newfoundland & Labrador dominated by hydro and/or nuclear power• Electrification of transit enables GHG reduction

• Saskatchewan, Alberta, Nova Scotia, New Brunswick rely heavily on coal and/or natural gas


Generation capacity info available from NRCAN (http://www.nrcan.gc.ca/energy/electricity-infrastructure/18792)

http://www.nrcan.gc.ca/energy/electricity-infrastructure/18792


• Ontario’s electricity supply is not carbon intensive• Predominantly nuclear and hydro

• Embedded generation projects (local distribution companies) – mostly solar and wind (>2500 MW total)

Ontario’s Energy Mix


Source: ieso power data http://www.ieso.ca/en/power-data/supply-overview/transmission-connected-generation

Ontario’s 2016 Transmission-Connected Energy Output


Hydrogen as an energy carrier


With H2 Production & Storage

Benefits:

1. Storing energy from intermittent energy sources

2. Localization or elimination of pollutants

With No Storage

WindHydro

SolarNuclear

Geothermal

Continuous IntermittentBackstop / Demand Response

Coal

Natural Gas

Consumption

WindHydro

SolarNuclear

Geothermal

Continuous Intermittent

Consumption

Electrolyzer

Fuel Cell




Source: NREL (USDOE) H2 at Scale Presentation https://www.nrel.gov/docs/fy16osti/66246.pdf

• Hydrogen production enables greater penetration of intermittent wind and solar generation

• Hydrogen can provide large scale, long-term storage for electricity




• Hydrogen production enables greater penetration of intermittent wind and solar generation

• Hydrogen can provide large scale, long-term storage for electricity

Source: IEA technology roadmap: Hydrogen and Fuel Cells (2015)https://www.iea.org/publications/freepublications/publication/TechnologyRoadmapHydrogenandFuelCells.pdf


Fuel Cells and Electrolyzers



Polymer Electrolyte Membrane (PEM) Fuel Cells:

• Produce electricity from H2 and air

• Do not generate CO2 at point of use

• No combustion• Direct H2 (< 90°C)

Background: Polymer electrolyte membrane fuel cells

11

O2

GDLPEMGDL

H2

e-DC circuit

H2O

H2O

H+Anode

H2 2H+ + 2e-

Cathode

½ O2 + 2H+ + 2e-

H2O

Catalyst Layer

Gas diffusion layer (GDL)

Catalyst-coated membrane (CCM)


PEM Electrolyzers:

• Water + H2 and O2

• Do not generate CO2 (unlike SMR)• Preferred method of H2 generation

• Not yet most common

Background: Polymer electrolyte membrane electrolyzers

12

H2

PTLPEMPTL

O2

e-DC circuit

H2O

H2O

H+

Catalyst Layer


Fuel cells and electrolyzers

Advantages over batteries for mobile applications:

• Range scales with tank size, not fuel cell stack size (cost advantage for longer-range applications)

• Shorter fueling time (~5 minutes for a hydrogen fuel cell car)

• No performance loss as tank is being depleted



Future of low GHG transportation: FCEV + BEV

• Both FCEVs and BEVs will be relevant!


Figure from The Hydrogen Council Vision Report. (www.hydrogeneurope.eu) Weight and range estimates from Toyota, Hyundai, Daimler

http://www.hydrogeneurope.eu/


Today’s market for hydrogen fuel cells

Material handling (forklifts)

• Advantages:• Fuelling time

• Space saving (no battery charging rooms)

• No loss of power during discharge

• On-site hydrogen generation in off-peak hours

• Food distribution, manufacturing, retail distribution facilities switching to fuel cells based on cost and productivity advantages


Ballard Power Material Handling Solutionshttp://www.ballard.com/markets/material-handling

PlugPower Gendrive Series 2000http://www.plugpower.com/products/gendrive/series-2000/



Fuel cell buses

• Zero-emission 1:1 replacement for CNG or diesel buses • same range/route flexibility, similar refueling time

• Governments (esp. China) pursuing for urban air quality improvements

• Case studies, white papers available: ballard.com/markets/transit-bus


Blue-G/Hydrogenics (Mississauga) fuel cell bus (promotional image - Hydrogenics Nov 2017 Investor Presentation)

http://www.ballard.com/markets/transit-bus



Hydrogen-powered rail transit (hydrail)

• Governments/municipalities in Europe and China are showing growing interest in fuel cells for trains

• Alternate form of rail electrification

• Advantages over traditional catenary system:• Gradual rollout, no service interruption

• Resilience to extreme weather

• H2 production during off-peak hours, less strain on electrical grid

• Kickstart H2 production infrastructure


Alstom Coradia iLint (alstom.com/press-centre)



Canadian companies are producing the fuelcells for global hydrail projects!

• Alstom and Hydrogenics (Mississauga) have partnered to deliver hydrogen-powered trainsin four German states

• Ballard (Burnaby, BC) has signed a developmentagreement with Siemens for fuel-cell powered commuter train

• Ballard also supplying fuel cells for CRRC (Chinese train co.) hydrail projects


Alstom Coradia iLint (alstom.com/press-centre)

Source: Ballard Power (http://ballard.com/about-ballard/newsroom/news-releases)



• Rail and bus transit generally operated by a government body• Motivated to achieve public health & environmental goals

• May be open to innovation (also may be especially hesitant!)

• Longer-term planning: transit infrastructure choices are decades-long commitments



Hydrail in Ontario?

• Metrolinx is launching a feasibility study on electrifying the GO rail network using hydrogen fuel cells (http://www.gotransit.com/electrification)


gotransit.com/electrification

http://www.gotransit.com/electrification


Platinum Usage in PEM Fuel Cells



Why PEM fuel cells require platinum

• Low temperature PEM fuel cells are most suitable for mobile power applications (weight, start-up time)

• Best catalysts for hydrogen oxidation and oxygen reduction reactions: platinum-group metals (Pt and Irmainly).• With a poor catalyst, reaction activation barrier is larger

• More heat is created (less efficient), and the electrical output is at lower potential (V)


O2

PEM

H2 H+

Catalyst Layer

H2O

H2O


The cost of Pt in fuel cell systems

• Costs associated with the catalyst layers are nearly half of the estimated mass-production stack cost


Stack cost breakdown (500,000 stacks/year)

*https://www.hydrogen.energy.gov/pdfs/15015_fuel_cell_system_cost_2015.pdf

• Cost reductions required (+carbon pricing) to significantly displace ICEs


The cost of Pt in fuel cell systems

Platinum mining

• Top 3 producers (with >90% of global resource):

• Major markets: consumer electronics, automotive sector (catalytic converters)

• Socio-political factors may affect price and availability• Sanctions & trade relations• Political unrest• Strikes/labour disputes (~5 month strike at 3 major South Africa Pt mining

companies in 2014)• Depletion not yet a major concern



The need for platinum-group metals (PGMs)

• Non-PGM catalysts under development (eg. Fe-based),• performance and/or durability currently not sufficient for transportation or power

generation applications.

• Current best approach: minimize Pt usage (maximize utilization), and ensure recyclability.

• The more Pt we use, the more stack cost will track with a precious metal’s commodity price



How do we reduce the platinum requirement?

• Fuel cell systems are constructed with up to several hundred individual “cells” connected in a “stack”

• Reduce Pt by:• Reducing Pt loading in catalyst layers of each cell• Reducing # cells per stack (increase power density in remaining

cells)


Ballard Power Fcgen 1020ACS ballard.com/fuel-cell-solutions


Mass transport limitations in PEM fuel cells

• On cathode side, water is produced• Must exit cell through gas channels

• Oxygen must diffuse across the GDL to reach the catalyst layer

27

GDL

Cathode

½ O2 + 2H+ + 2e-

H2O

Catalyst Layer

H2O

H2O

O2



• Liquid water accumulates in GDL• decreases the open pore space

• lengthens oxygen diffusion pathways

• Liquid water accumulation is most severe at high current density

• If Pt loading is decreased in catalyst layer• Reduced # reaction sites, larger transport

resistance in the catalyst layer

• Resistance to oxygen transport must be kept small in all fuel cell layers to prevent O2starvation

28

O2

GDL

H2O

Cathode

½ O2 + 2H+ + 2e-

H2O

Catalyst Layer

H2O



Focus of my research:

• Liquid water accumulation and O2 transport behavior• Inlet gas humidity

• GDL porosity

• Operating current density (rate of water production)

29

O2

GDL

H2O

Cathode

½ O2 + 2H+ + 2e-

H2O

Catalyst Layer

H2O


Ongoing research around the world: catalyst layer development

• Industrial and academic research groups around the world are focusing on studies of catalyst layer performance and durability• Improving transport of O2 to Pt particles in catalyst

• Catalyst nanostructure characterizations

• Catalyst oxidation states, catalysis reaction pathways

• Developing novel catalyst application methods

• Developing non-PGM catalysts


Nonoyama et al. 2011 (Toyota), J. Electrochem. Soc


Summary

• An exciting, growing field, albeit with challenges ahead• Real, feasible pathway to eventual cost-competitiveness

• Research to cut catalyst costs, improve performance• Increased production volumes

• Biggest challenge is public acceptance• H2 production, storage, delivery and use are safe in a well-regulated environment

• On-board storage tanks engineered to meet or exceed industry standards for crash safety• H2 dissipates quickly in leak scenarios (minimal explosion risk, counter to public perception)

• Rail and heavy transit adoption will accelerate technological development• Boom in demand from Europe and China for H2-powered transit

Spaces to watch:

Canada: Hydrogenics, Ballard, Hydrogen Business Council of Canada, Canadian Hydrogen Fuel Cell Association

US: US DOE VTO Consortia: FC-PAD, HydroGEN, HyMARC, ElectroCat

Europe: The Hydrogen Council (hydrogeneurope.eu) Fuel Cells and Hydrogen Joint Undertaking (FCH JU), Hydrogen Mobility Europe (h2me.eu)


Thermofluids for Energy and Advanced Materials (TEAM) Laboratory (bazylak.mie.utoronto.ca)

Contact Info:Daniel Muirhead M.A.Sc., B. [email protected]

Acknowledgements

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