2Hydrogen (H2) is a fuel not an energy source Hydrogen (H2) is a fuel not an energy source. It is the most abundant element but must be removed from larger molecules like water or petroleum.
3Production Hydrogen can be produced from Fossil Fuels (currently 90% of 42 mtons/yr)Water
4Production Fossil Fuels Coalconverted to mixture of hydrogen (50%), methane (35%), and carbon monoxide (8%)Steam Reforming Methane (SRM)Most efficient, widely used, and cheapestPartial OxidationRange of feed stocks, 75% SRMDirectly cracking Methane or other hydrocarbons
5Production Fossil Fuels The downside:All of these methods release CO2
6Production Water: Electrolysis Electricity + H2O → H2 + O + H2O (steam)Large-scale units using alkaline electrolyte can run at 70–75% efficiency (EE - H2 )Smaller systems with polymer electrolytes reach 80–85% efficiency (EE - H2 )Steam electrolyzers in development may be able to reach 90% efficiency (EE - H2 )
7Production Water: Electrolysis When using electricity generated from thermal power stations the overall efficiency of converting fossil fuel to hydrogen via electrolysis would, typically, be only about 30%. (Rand, Dell, 2005)CO2 is released at the power plant
8Production Water: Direct Methods ThermochemicalCould utilize waste heat from a nuclear plantCould be achieved with solar mirrorsPhotoelectrolysis – sunlight to H2presently only 1–2% efficiencynew technique reporting 4.5% efficiencyBiophotolysis – algae to H2
10Hydrogen StorageThe Challenge: store large amounts of hydrogen at ambient temperature and pressure.-compressed gas tanks-cryogenic liquid hydrogen tanks-metal hydrides-chemical reactions (e.g. hydrolysis)-nanomaterialsOne solution: a three-dimensional lattice of tiny hollow cubes, each capable of storing eight hydrogen molecules insideJeff Long, UC-Berkeley
11Hydrogen StorageJ.T.S. Irvine / Journal of Power Sources 136 (2004) 203–207
12Uses Ways to release the energy Catalytic CombustionHigh control, low temperatures possibleHeating, cookingDirect Steam GenerationBurn it with pure oxygen to form pure steamPeak load generationInternal Combustion EngineMore efficient (20%) less powerful (15%) than gasoline ICECan be used in gas turbines and jetsFuel Cells
13Uses Fuel CellInputs: Hydrogen OxygenOutputs: Electricity Water Heat
15Uses Types of Fuel Cells Overall reaction is the sameH2 + ½ O2 → H2OLow temperature fuel cellsAFC, PEMFC, PAFC, DMFCHigh temperature fuel cellsMCFC, SOFCPolymer Electrolyte MembraneVehiclesSmall-scale distributed power generation
17Uses Applications of Fuel Cells Portable Devices (Direct Methanol)Cell PhoneLaptopsField Equipment for militaryDistributed GenerationCommercial and Residential stationaryLight Duty Vehicles
18Uses Applications of Fuel Cells V. Ananthachar, J.J. Duffy / Solar Energy 78 (2005) 687–694
19Energy/National Security Total U.S. primary energy production and consumption, historical and projected, 1970 to 2025.SOURCE: EIA (2003)
20Energy DiversityU.S. primary energy consumption, by fuel type, historical and projected, 1970 to 2025.SOURCE: EIA (2003).
21Environment/Climate Change U.S. emissions of carbon dioxide, by sector and fuels, SOURCE: EIA (2002)
22Environment/Climate Change Estimated volume of carbon releases from passenger cars and light-duty trucks: current hydrogen production technologies (fossil fuels), 2000–2050. Source: NAS
23Public Health Particulate air pollution Smog Other air pollutants htttp://airnow.gov
24Feasibility of a U.S. Hydrogen Economy Steven Smriga Scripps Institution of Oceanography
25Policy and Political Milestones 2002: U.S. President Bush launches FreedomCAR, a partnership with automakers to advance research needed to increase practicality and affordability of hydrogen fuel cell vehicles2003: Bush State of the Union Address announces $1.2 billion hydrogen fuel initiative to develop technologies for hydrogen production and distribution infrastructure needed to power fuel cell vehicles and stationary fuel cell power sources2004: Governor Schwarzenegger launches California’s Hydrogen Highway Network initiative2005: CA Senate Bill 76: $6.5 million in funding for state-sponsored hydrogen demonstration projects through 2006
26Hydrogen Production using Domestic Resources Major driver: Reduction in dependence on foreign oil“The U.S. Department of Energy estimates that the hydrogen fuel initiative and FreedomCAR initiatives may reduce our demand for petroleum by over 11 million barrels per day by 2040 – approximately the amount of oil America imports today.”“America imports 55 percent of the oil it consumes; that is expected to grow to 68 percent by 2025.”-www.whitehouse.gov, January 2003
27Hydrogen Production using Domestic Resources Consumption factor*Coal1.3Natural gas1.2Biomass2.4Domestic oil??Wind140Solar>740Nuclear3.2*Factor by which U.S. would need to increase current consumption of this resource to produce required hydrogen equivalentSource: U.S. Dept. of Energy, H2 Posture Plan, 2004
28Source: National Fuel Cell Research Center, UC-Irvine
29Hydrogen: Toward Zero Emissions Combined heat and power systemsCarbon capture and storageFuture energy sources: wave, geothermal, nuclear fusionEnergy storage of renewablesModules that couple wind and solarwith hydrogen productionCapture intermittent outputBatteries may be superior for short termapplicationsContributes to distributed generation
30Making Fuel Cells Affordable Barriers include:durabilityfuel supply (some FCs require extremely pure fuel), andraw materials (e.g. platinum and other precious metals used as a catalyst)
31Making Fuel Cells Affordable Factors toward weakeningthese barriers:Widespread fuel cell vehicle demonstration projectsCalifornia Hydrogen Highway (e.g. Chula Vista)Canada, Japan, EU, othersFuel cells already used in stationary power backup systemsPublic-private partnerships and alliances setting goalsSolid State Energy Conversion Alliance (SECA)
32The overall U. S. hydrogen market is estimated at $798 The overall U.S. hydrogen market is estimated at $798.1 million in 2005 and is expected to rise to $1,605.3 million in 2010.The overall European hydrogen market is estimated to be about $368 million in 2005 and is expected to grow to $740 million in 2010.Source: Fuji-Keizai USA, Inc.: 2005 Hydrogen Market, Hydrogen R&D and Commercial Implication in The U.S. and E.U.
33Reduction in Carbon Emissions hydrogen fuel cell efficiency: 40-60% combustion engine efficiency: ~35%potential for cleaner energy productionSource: U.S. Dept. of Energy
34Transition to Hydrogen Vehicles Possible optimistic market scenario showing assumed fraction of hydrogen fuel cell and hybrid vehicles in the United States, 2000 to Sales of fuel cell light-duty vehicles and their replacement of other vehicles are shown.Source: The Hydrogen Economy: Opportunities, Costs, Barriers, and R&D Needs (2004); National Academies Press.
37Challenges to the Hydrogen Economy Ted BeglinTwo aspects:FeasibilityMisalignment with goals
38Can it happen? Feasibility Chicken and the EggCost of infrastructureCompetitionStoragePublic PerceptionLand Usage
39Can it happen? Chicken and the Egg The FCV market depends upon the availability of a hydrogen infrastructureThe hydrogen infrastructure must be promoted by hydrogen useNeither serves any purpose without the other
40Can it happen? Cost of Infrastructure Replacement value of the current energy system and related end-use equipment would be in the multi-trillion-dollar rangeBoth the supply side (the technologies and resources that produce hydrogen) and the demand side (the technologies and devices that convert hydrogen to services desired in the marketplace) must undergo a fundamental transformation.In no prior case has the government attempted to promote the replacement of an entire, mature, networked energy infrastructure before market forces did the jobMarket pressures from lacking petroleum supplies and/or US participation in a CO2 credit-trade market are needed to push this forwardNAS, 2004
41Can it happen? Competition Incumbent technologies do not stand still, but continue to improve.The cost of the current energy infrastructure is already sunk, favoring technologies that use it.Gasoline, Diesel, and CNG Hybrid VehiclesBio-diesel and Ethanol
43Can it happen? StorageGoals for Hydrogen On-Board Storage to Achieve Minimum Practical Vehicle Driving RangesEnergy DensityGeneral Motors Minimum GoalsCompressed/Liquid Hydrogen (Currently)DOE GoalMegajoules per kilogram64/1010.8Megajoules per liter3/49.72NOTES: Energy densities are based on total storage system volume or mass. Energy densities for compressed hydrogen are at pressures of 10,000 psi.SOURCES: DOE (2002b, 2003b)
44Can it happen? Storage Compressed gas tanks Lacks energy to volume ratioFor example, for more than a 200-mile driving range, today’s natural gas vehicles usually require two 5,000 psi tanks or one 10,000 psi tank, taking up most of the trunk. (NAS)Cryogenic liquid hydrogen tanksAbout 30% of the energy in the hydrogen is wasted in the liquefaction and filling processEmptying equipment is both complex and costlyBoil-off rate is such that the liquid can only be stored for a few days at most. (Rand, Dell 2005)
45Can it happen? StorageAdvanced methods may have to provide the solution, but are still in developmentmetal hydrideschemical reactions (e.g. hydrolysis)nanomaterials
46Can it happen? Public Perception Public perception of safety is affected by Hindenburg SyndromeHowever, it is not clear that H2 is any more dangerous than natural gas or gasolineIrony: Because of high diffusion, it may be saferAddison Bain, NASA veteran presented compelling evidence in 1997 that the Hindenburg’s cotton covering was coated by a substance with similarities to rocket fuel. The same ship filled with inert helium still would have burned.Peter Hoffman, Tomorrow’s Energy, 2001
47Can it happen? Land Usage New transmission lines are increasingly difficult to build, largely because of public opposition.The transmission system is being used for purposes for which it was not originally designed, and upgrades are not keeping pace with the increasing loads on it.Unless this situation is corrected, it may hamper the use of electrolyzers in distributed hydrogen generation facilities.Building pipelines to carry hydrogen may encounter some of the same sitting problems.
48Should it happen? Reliance on Natural Gas rather than Oil Carbon SequestrationPicking a winner
49Should it happen? Energy/National Security We could be trading one foreign dependency for anotherThe initial hydrogen economy would most likely depend upon the reforming of natural gasIf natural gas is used to produce hydrogen, and if, on the margin, natural gas is imported, there would be little if any reduction in total energy imports, because natural gas for hydrogen would displace petroleum for gasoline.NAS, 2004
50Should it happen? Environment/Climate Change Two sources of carbon stand outCoal burned for electricityPetroleum burned in transportation fuelsHydrogen must address both to benefit the environmentU.S. emissions of carbon dioxide, by sector and fuels, SOURCE: EIA (2002)
51Should it happen? Environment/Climate Change Successful carbon sequestration is necessary, otherwise CO2 from petroleum will come from fossil fuel reformation to produce hydrogenEnergy shifted from oil could result in massive coal mining to make up the differenceEnergy/National security would be addressed but not greenhouse gasesConservation, advancement of renewables, and nuclear power would be the only emission free hydrogen if CO2 sequestration is not realized
52Should it happen? Public Health Although fuel cells only emit water, internal combustion use produces NOx, leading to smogUnintended consequences of H2 leakage may include reduction in global oxidative capacity, increase in tropospheric ozone, and increase in stratospheric water that would exacerbate halogen induced ozone losses (Dubey, Los Alamos National Laboratory, 2003)
53Should it happen? Energy Diversity Quite the opposite, it could reduce us to predominately rely on coalThe hydrogen economy needs support from some combination of increased renewable power, reinvigoration of nuclear power, and conservation to promote diversity
54Should it happen? Energy Diversity Picking winners?The track record50s Nuclear power “too cheap to meter”Late 70s, early 80s oil price assumptions to justify large amounts of spending90s battery powered carsOther technologies, should funding favor H2?Battery technologyBiomass based fuels
56Physical and regulatory infrastructure Safety codes and standardsPublic awareness about fueling systemsTraining for fuel distribution personnel
57Types of Fuel Cells Alkaline Fuel Cell (AFC) Molten Carbonate Fuel Cell (MCFC)Phosphoric Acid Fuel Cell (PAFC)Proton Exchange Membrane Fuel Cell (PEMFC)Solid Oxide Fuel Cell (SOFC)Direct Methanol Fuel CellFuel cell types are generally characterized by electrolyte material. The electrolyte is the substance between the positive and negative terminals, serving as the bridge for the ion exchange that generates electrical current.