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What is Hydrogen?

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Part I:Hydrogen Energy System Basics


What we need from our energy system• Most Americans do not think about energy unlessthe lights go out or the price at the pump skyrockets• BUT, access to clean, reliable, affordable andsustainable energy is vital to maintaining andenhancing our standard d of livingi


What we need from our energy system• Any energy system, including our currentone, needs to have certain characteristics– Security of supply• Domestic production• Flexibility of sources• Sustainability– Environmental quality• Reduced d harmful emissions i (smog, particulates)t • Low GHG emissions• Sustainability– Economic benefits• Efficient and reliable• Accessibility• Stable prices• Job creation


Current US Resource BaseCoalPetroleum23% Uranium37% 9%BiomassRenewables7%Natural Gas24%Conventional HydroIs this diverse enough ?GeothermalWindSolar


Energy Consumption by SectorTwo-thirds of oil is used in Transportation SectorThe rest is used to produce chemicals (IndustrialSector) and heating oil (Residential & Commercial)Electricity for energy services(lighting, cooking, ventilation,cooling, computing, etc)Natural gas for heating, cooking


US Primary Energy Consumption


Transportation Energy UseLight-DutytVehicles59%Military3%Air10%Pipeline Fuel2%Trucks19%Rail2%Bus1%Marine4%Transportation Sector is 97% petroleum-based60% of the petroleum we use is imported, and the gap isgrowing every day


Mega ton ns of oil equivalent2000150010005000-500ImportsChina’s oil imports nearlyTRIPLED between 2003 and2006 (data in the 2005 and 2008WEO reports), and vehicleownership continues to rise-1000Notes: Taken from IEA 2008 Key World Energy Statistics (2006 data)USA included in OECD – also plotted separately to show contribution


CO 2 Emissions per Capita2018TonnesCO2/ca apita1614121086420Notes: Taken from IEA 2008 Key World Energy Statistics (2006 data)USA included in OECD – also plotted separately to show contribution


What is Hydrogen?• Element 1 on the Periodic Table– 1 proton, 1 electron• Diatomic molecule (H 2 )– 2 protons, 2 electrons• Highest energy content of common fuels on a WEIGHT basis• Lowest energy content of common fuels on a VOLUME basis• “H” is abundant on earth, but usually bound to carbon (such as CH 4 ) oroxygen (H 2 O) or both (organic matter – “carbohydrates” – C 6 H 12 O 6 )• H 2 is not found in nature in large quantities (although there are someunderground gas deposits that have relatively high concentrations of H 2 )


Flexibility of Source• Hydrogen can be produced from Biomasswater; from carbon-containingmaterials (usually reacting withwater); as a byproduct of chemicalprocessesHydroWindSolar• Every region has someindigenous fossil or renewableresource that can be used tomake hydrogen– Regional variations in traditionalenergy resources are no longer (ascritical) economic, political, orsecurity issuesGeothermalNuclearOilCoalNaturalGas


Renewable Resources


Fossil and Uranium Resources


Production Potential fromDomestic Resources• As an example, how could the US fuel half of thecurrent fleet with hydrogen?– Current annual consumption in the light-duty market is 16 quads ofgasoline• Quad is short for Quadrillion (10 15 )BTUBTUs• One quad is about 8 billion gallons of gasoline, or about 230 millionbarrels of crude oil (making current consumption ~3.7 billion barrels of oilannually, for light-duty vehicles only)– Assume a 2x increase in efficiency i with hydrogen fuel cell vehicles– For half of the fleet, we need 4 quads– This is 36 (let’s call it 40) million tons of hydrogen per year (~4 timesthe current domestic hydrogen production, mostly from natural gas)• Using only ONE domestic resource, can we make thismuch hydrogen?– We will, of course, use a combination of resources, but this is aninteresting and eye-opening exercise


Production Potential fromDomestic ResourcesFor 40 million tons/year of hydrogen, we would need:OROROROROR95 million tons of natural gas (current consumption is around 475 million tons/yearin all energy sectors)280-560 million tons of coal (current consumption is around 1,100100 milliontons/year)400-800 million tons of biomass (availability is 800 million tons/year of residueplus potential of 300 million tons/year of dedicated energy crops with no food,feed or fiber diverted)The wind capacity of North Dakota (class 3 and above)3,750 sq. miles of solar panels (approx. footprint of the White Sands Missile Range)140 dedicated conventional nuclear power plants


Hydrogen from RenewablesPer Area Potential


Hydrogen From RenewablesPer Person Potential


So We Can Produce Hydrogen -Now What?• Storage of hydrogen on board is a tough technical challengeWhere doyou thinkgasolinefits onthischart?Answer:It doesn’t~180 g/Land 26wt%From DOE presentation at the HTAC meeting, November 2009


So We Can Produce Hydrogen -Now What?• Installation of a hydrogen delivery erand dispensinginfrastructure is an expensive proposition (maybe)– Hydrogen pipelines exist in some industrial areas (aroundthe Gulf Coast, for example)– Most merchant hydrogen is delivered as a liquid incryogenic tanker trucks or as a compressed gas in tubetrailers (depending on demand)– Electrolysis is a great option if the user needs a relativelymodest amount of extremely high-purity hydrogen• To realize the benefits of a hydrogeneconomy, we actually have to put a valueon energy security and environmentalimpacts, and bear some incremental cost


Flexibility of Use• In the Transportation Sector– Desired range can be achieved with on-board hydrogenstorage (unlike BEV – let’s talk about this later)– Can be used in ICE (with modification, very low emissions);preferred for fuel cell (no emissions); APUs– Trains, automobiles, buses, and ships• In the Buildings Sector– Combined heat, power, and fuel– Reliable energy services for critical applications– Gidi Grid independenced• In the Industrial Sector– Already yplays an important role as a chemical– Opportunities for additional revenue streams


Part II:Fuel Cell Technology


Battery vs Fuel CellanodeLoade - Similarities: half reactions, separation ofionic and electronic pathways, directcathodeconversion of chemical energy intoElectrolyteelectrical energyIonsBatterye -LoadReactant (H 2 ) Oxidant (O 2 )Differences: breaking of covalent bonds(battery) versus addition and removal ofreactants and products (fuel cell); closed(battery) versus open (fuel cell) systemProductsPorousanodeElectrolyteIonsPorouscathodeProductsFuel CellAdvantages: fuel cell energy density is up to>6000 Whr/kg based on fuel versus batteryenergy density is up to 150 Whr/kg; refuel(fuel cell) versus recharge (battery)Disadvantages: fuel cell cost reliability fuelDisadvantages: fuel cell cost, reliability, fuelstorage


Combustion vs Fuel CellFuel cells do not operate through a Carnot Cycle (they are not heatengines) and can therefore be more efficient than processes thatdirectly involve combustion. Pollution is typically greatly reduced.*taken from Fuel Cells, Appleby, 1987.


TypeHydrogen Fuel Cell TypesMobileIonTemp ofOperationUses Benefits IssuesAlkaline OH - 150-200C Manned space flights Produces drinking water for Extremely sensitive to(AFC)(starting w/ Apollomissions)Some interest in vehicleuseastronauts and heat for thespacecraftHighly reliableCO 2PhosphoricAcid(PAFC)MoltenCarbonate(MCFC)Solid Oxide(SOFC)PolymerElectrolyteMembrane(PEMFC)H + 150-200C Stationary powerCombined Heat andPower (CHP)CO2-3~650C Stationary powerCHPO 2- 800-1000C Stationary powerCHPAuxiliary Power Units(APUs)H + 50-80C VehiclesPortable appliancesStationary ti powerElectricity-only efficiency of ~40%Improved efficiency with CHPReliable operation CommercialhistoryElectricity-only efficiency of ~60%High efficiency(80-85%) 85%) with CHPFuel flexibilityNoble metal catalyst not requiredElectricity-only efficiency of 50-60%80-85% efficiency for CHPFuel flexibilityNoble metal catalyst not requiredSolid electrolyteFast startupHigh power densityCost reductions havestagnated($3500-4500/kW)Long startup timeDurabilityCostLong startup timeDurabilityCostCostDurabilitySensitivity to CO and H 2 S


Polymer Electrolyte Membrane(PEM) Fuel Cells• The PEM fuel cell was initially developed for the firstGemini spacecraft, but did not meet the reliabilityrequirements of NASA• Development languished for decades, untilimprovements made at Los Alamos NationalLaboratory led to a resurgence of interest in the late1980s and early 1990s• The centerpiece of the PEM fuel cell is the solid, ionconductingpolymer membrane.– Typically made from a tough, Teflon-like like material invented byDuPont called Nafion TM• This material is unusual in that, when saturated with water, itconducts positive ions but not electrons• Exactly the characteristics needed for an electrolyte barrier


Schematic of PEM Fuel CellThe membrane is sandwichedbetween the anode andcathode electrode structures,which are porous conductingfilms, about 50 micrometersthick. The electrodes consistof carbon particles that havenanometer-size platinumparticles bonded d to them, in aporous matrix of recastNafion TM . The carbon particlesprovide the electron-conducting path, while theNafion TM provides an ionconductingpath to themembrane.


Schematic of PEM Fuel CellIn addition to having catalytic,electric- and ion-conductingproperties, the electrodes and thesupporting backing material arecrucial to water management.This, and the control of gas flowsin and out of the cell, are key toefficient cell operation:• too little water at the cathode, themembrane begins to lose the abilityto conduct ions.• too much water, it floods the porouselectrodes and prevents oxygenfrom diffusing to the catalyticallyactive sites.


PEM Fuel Cells• Transportation is the key target/focus area ofefforts to develop and commercialize PEMfuel cells, although not the only area ofinterestt• Low temperature (~80°C) PEM fuel cells– Less “waste” heat, and higher electrical efficiency– Limits CHP applications compared to other fuelcell types– Quick startup, lower thermal stresses• Efficient at low loads (typical operating regionfor vehicles)


How PEM Fuel Cells WorkRight click mouse here for movie menuhttp://www.lanl.gov/orgs/mpa/mpa11/animation.htm


From GM presentation at the HTAC meeting, November 2009


BREAK!!!!


Part III:Environmental, Energyand Economic Implications


Environmental, Energy andEconomic ImplicationsCurrent Technology:Central Station Hydrogen from Steam Methane Reforming3.0 kg CO 28.9 kg CO2Natural GasNatural Gas Productionand DistributionSteam MethaneReforming1kgHydrogen(Plant Gate)183 MJ 160 MJ 142 MJη = 77.6%1 kg hydrogen produces 11.9 kg CO 2 -equivalent emissions (stoichiometry says 5.5 kg CO 2 )


Environmental Implications4035kg CO2/k kg hydrogen30252015delivery to consumerhydrogen (plant gate) ->1050liquid - 100liquid - 1000compressedcompressedpipeline - 100pipeline -miles miles gascyclinders -100 milesgascyclinders -1000 milesmiles 1000 miles


Energy Implications20015010050MJ/kg hy ydrogen0-50-100-150natural gas feed ->hydrogen (plant gate)->delivery to consumer-200-250liquid - 100 miles liquid - 1000 miles compressed gascyclinders - 100milescompressed gascyclinders - 1000milespipeline - 100 miles pipeline - 1000 miles


Economic Implications141210delivery to consumerhydrogen (plant gate) ->ogen$/kg of hydr86420liquid - 100 miles liquid - 1000 miles compressed gascyclinders - 100 milescompressed gascyclinders - 1000milespipeline - 100 milespipeline - 1000 miles


Environmental Implications• Conventional Gasoline ICE– Well-to-Wheels:• Car similar to Chevy Malibu (2010 fuel economy andemission numbers from www.fueleconomy.gov)• 0.5 kg CO 2-equivalent /mile driven, for fuel economy of 22 mpg(combined driving), full fuel cycle basis• For 15,000 miles driven per year: 7,545 kg CO 2-equivalent /year• Hydrogen FCV: zero tailpipe CO 2 emissions– Well-to-Wheels:• At 60 mpgge (~60 mpkg): 250 kg hydrogen needed yearly• No CO 2 from the tailpipe• only need to do better than 30.2 kg CO 2-equivalent /kg hydrogenfor production and delivery (if we compare to conventionaltechnology)


Environmental ImplicationsConventional Gasoline Vehicle and Hydrogen Fuel Cell Vehicle4035kg CO2/k kg hydrogen30252015delivery to consumerhydrogen (plant gate) ->Conventional Gasoline ICE1050liquid - 100liquid - 1000compressedcompressedpipeline - 100pipeline -miles miles gascyclinders -100 milesgascyclinders -1000 milesmiles 1000 miles


Environmental Implications• Compressed Natural Gas ICE– Well-to-Wheels:• Car similar to Honda Civic CNG (2009 fuel economy andemission numbers from www.fueleconomy.gov)• 0.33 kg CO 2-equivalent /mile driven, for fuel economy of 28 mpg(combined driving), full fuel cycle basis• For 15,000 miles driven per year: 4,909 kg CO 2-equivalent /year• Hydrogen FCV: zero tailpipe CO 2 emissions– Well-to-Wheels:• At 60 mpgge (~60 mpkg): 250 kg hydrogen needed yearly• No CO 2 from the tailpipe• only need to do better than 19.6 kg CO 2-equivalent /kg hydrogenfor production and delivery (if we compare to conventionaltechnology)


Environmental ImplicationsCNG Vehicle and Hydrogen Fuel Cell Vehicle403530delivery to consumerkg CO2/k kg hydrogen252015hydrogen (plant gate) ->CNG vehicle1050liquid - 100liquid - 1000compressedcompressedpipeline - 100pipeline -miles miles gascyclinders -100 milesgascyclinders -1000 milesmiles 1000 miles


Environmental Implications• Gasoline hybrid – the real competition?– Well-to-Wheels:• Toyota Prius (2010 fuel economy and emission numbersfrom www.fueleconomy.gov)• 0.22 kg CO 2-equivalent /mile driven, for fuel economy of 50 mpg(combined driving), full fuel cycle basis• For 15,000 miles driven per year: 3,364364 kg CO 2-equivalent /year• Hydrogen FCV: zero tailpipe CO 2 emissions– Well-to-Wheels:Wheels:• At 60 mpgge (~60 mpkg): 250 kg hydrogen needed yearly• No CO 2 from the tailpipe– but need to do better than 13.5 kg CO 2-equivalent /kg hydrogen forproduction and delivery (if we compare to hybrid technology)


Environmental ImplicationsHybrid Gasoline Vehicle and Hydrogen Fuel Cell Vehicle4035 delivery to consumerhydrogen (plant gate) ->30kg CO2/k kg hydrogen252015Hybrid Vehicle1050liquid - 100liquid - 1000compressedcompressedpipeline - 100pipeline -miles miles gascyclinders -100 milesgascyclinders -1000 milesmiles 1000 miles


Environmental ImplicationsNear-Term Renewable Technology:Distributed Hydrogen from Wind Electrolysis0.7 kg CO 2WindFossil ResourcesWind Turbine –Construction & OperationElectrolysis andCompression0.2 kg CO 21kgHydrogen1 kg Hydrogen557 MJ167 MJ142 MJ9 MJ1 kg hydrogen produces 0.9 kg CO 2 -equivalent emissions (stoichiometry says 0 kg CO 2 )


Environmental ImplicationsHybrid Gasoline Vehicle and Hydrogen Fuel Cell Vehicle403530to customerhydrogen productionkg CO2/k kg Hydrogen25201510Hybrid Vehicle50liquidliquid, withcompressedvaporizationandcompressiongas


What about BEVs?Fuel Cell and Battery Electric Vehicles Compared, C.E. Thomas, IJHE, 34, 6005-6020, 2009.


What about BEVs?Fuel Cell and Battery Electric Vehicles Compared, C.E. Thomas, IJHE, 34, 6005-6020, 2009.


What about BEVs?Fuel Cell and Battery Electric Vehicles Compared, C.E. Thomas, IJHE, 34, 6005-6020, 2009.


From DOE presentation at the HTAC meeting, November, 2009: Program Record #9002


From DOE presentation at the HTAC meeting, November, 2009: Program Record #9002


Part IV:Hydrogen SafetyReal and Perceived


Fuel PropertiesPropertyHydrogenH 2MethaneCH 4MethanolCH 3OHGasolineBoiling point (°C) -253 -162 65 wide rangePhysical state at 25°C Gas Gas Liquid LiquidHeating Value - weight basisLHV (MJ/kg)HHV (MJ/kg)1201424853202342-4444-46Heating Value - volume basisLHV (MJ/Nm 3 ) 11 35 15,700 ~32,000HHV (MJ/Nm 3 ) 13 39 18,100 ~33,000Flammability limits (vol% in air) 4.1-74 5.3-15 6-36.5 1.4-7.6Explosive limits (vol% in air) 18.2-58.9 5.7-14 6.7-36 1.4-3Molecular l diffusion i coeff (cm 2 /sec) in air 061 0.61 016 0.16 013 0.13 005 0.05Autoignition temperature in air (°C) 571 632 470 220Liquid density (g/liter) 77 425 792 720-780Specific gravity at 25°C (water=1) - - .79 .72-.78Specific gravity at 25°C (air=1) .07 .55 1.1 3.5-4.5


From the Congressional Record 1875“A new source of power... called gasoline has been produced by aBoston engineer. Instead of burning the fuel under a boiler, it isexploded inside the cylinder of an engine...The dangers are obvious. Stores of gasoline in the hands of people pinterested primarily in profit would constitute a fire and explosivehazard of the first rank. Horseless carriages propelled by gasolinemight attain speeds of 14, or even 20 miles per hour. The menace toour people of this type hurtling through our streets and along ourroads and poisoning the atmosphere would call for prompt legislativeaction even if the military and economic implications were not sooverwhelming... the cost of producing (gasoline) is far beyond thefinancial capacity of private industry... In addition the development ofthis new power may displace the use of horses, which would wreckour agriculture.”


Public Acceptance• We can succeed technically, but still failif we don’t:– Involve the public early and often in thedemonstration of new technologies– Inform the public about hydrogen and fuelcells in ways they can understand– Address safety concerns, real andimagined


Project Considerations:Community Buy-In• Community support activities should begin very early in projectdevelopment to allow ample time for education, feedback, andmodifications, if needed. Community members may beunfamiliar with fuel cells, hydrogen fuels, and hydrogen safetyand may have concerns about the project. If such concerns arenot addressed, project development may be severely delayed oreven cancelled.• Community buy-in activities may includeeducational presentations, open forums, andother events hosted by the developer orzoning officials. Such activities may beperformed simultaneously with zoning andsite selection.The Benning Road hydrogen fueling stationin Washington, DC, was delayed one yearbecause of community concerns.


Hydrogen Safety?Moral of theStory ?Don’t paintyourdirigiblewith rocketfuel !Hindenberg, 1937Colorized photo shows burning of outer fabric of dirigible


Hydrogen SafetyHydrogenGasoline3 seconds1 minute• Fuel leak simulation–Hydrogen on left–Gasoline on right–Equivalent energyrelease• Single-mode failureassessmentWhich car would you rather be in?


So – why hydrogen?• It really is all about security– Energy security• Diverse domestic sources• Flexibility of system– Economic security• International leadership in technologydevelopment and deployment• Balance of payments• Price stability– Environmental security• Potential to meet GHG targets: withrenewables or fossil with sequestration• Urban air quality improvements• Reduction in air pollutantst


Post-Quiz


Quiz Answers – True or False•Hydrogen pipelines exist nationwideFalse•In a hydrogen economy, hydrogen replaces fossil fuels as thedominant form of energyTrue•Hydrogen gas is toxic False•Fuel cells produce electricity through hydrogen combustion False•Hydrogen is too dangerous for everyday use by the general publicFalse•Hydrogen is lighter than airTrue•Hydrogen has a distinct odor False


Quiz Answers – Multiple Choice•In which state or condition can hydrogen be stored?a. chemical compoundb. liquidc. both of thesed. neither of these•When using pure hydrogen, fuel cell vehicles generate electricity, water, and what else?a. carbon dioxideb. nitrous oxidesc. heatd. all of these•Hydrogen can be produced using which of the following sources of energy?a. natural gasb. sunlightc. organic matterd. all of these•Which of the following represents a type of fuel cell?a. PDQb. PEMc. CFCd. none of these

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