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Fallacies of a Hydrogen Economy
2006 Byron Short Lecture2006 Byron Short LectureUniversity of Texas at AustinUniversity of Texas at Austin
Dr. Frank Kreith
““Let us set as our national goal in Let us set as our national goal in the spirit of Apollo, with the the spirit of Apollo, with the determination of the Manhattan determination of the Manhattan Project, that by the end of this Project, that by the end of this decade we will have developed decade we will have developed the potential to meet our own the potential to meet our own energy needs without depending energy needs without depending on any foreign energy source.”on any foreign energy source.”
President Richard Nixon, November 7, 1973President Richard Nixon, November 7, 1973
In response to President Nixon’s vision of U.S. energy independence, the National
Academy recommended in 1978:
• Conservation
• Synthetic fuels from coal
• Effective use of coal and nuclear power to produce electricity
• Use of solar energy for low temperature heat
“All the basic science funding in the world will have no positive effect on
the well being of our nation if the research is not carried out within a system that can effectively digest
and apply the results.”
George E. Brown, Jr., Chair of the House Committee on Science,
Space and Technology
Principal Energy Needs Principal Energy Needs of Society in 21of Society in 21stst
CenturyCentury
HeatHeatFuelFuel
ElectricityElectricity
Energy ProjectionEnergy Projection
1956 Edward Teller “Nuclear will be 1956 Edward Teller “Nuclear will be too cheap to meter.”too cheap to meter.”
1973 President Nixon “By 1980, we 1973 President Nixon “By 1980, we will be self sufficient and not need will be self sufficient and not need foreign energy.”foreign energy.”
1978 President Carter “In 20 years, 1978 President Carter “In 20 years, 20% of our energy will be from solar.”20% of our energy will be from solar.”
1980 President Reagan “Alaska has a 1980 President Reagan “Alaska has a greater oil reserve than Saudi Arabia.”greater oil reserve than Saudi Arabia.”
2003 President Bush “The first car 2003 President Bush “The first car driven by a child born today could be driven by a child born today could be powered by hydrogen.” powered by hydrogen.”
History of Hydrogen
• 1766 Henry Cavendish isolates hydrogen from the reaction iron- sulfuric acid
• 1781 A.L. Lavoirsier names “hydrogen” for “maker of water”.• 1783 Montgolfier brothers launch a hydrogen balloon in France.• 1820 Michael Faraday generates hydrogen by electrolysis• 1839 W.R. Grove demonstrates fuel cell to generate electricity.• 1870 Jules Verne states in his novel The Mysterious Island that
“hydrogen…will furnish an inexhaustible source of heat…”• 1871 Nikolaus Otto uses a 50% hydrogen mixture to run an
automobile engine• 1937 Hindenburg zeppelin explodes at Lakehurst.• 1973 Engineers all over the world investigate thermochemical cycles
for hydrogen production with nuclear reactors. • 1981 R. Shinnar et al show that thermo-chemical cycles for hydrogen
production are inferior to electrolysis.• 2002 DOE prepares a National Hydrogen Energy Roadmap
In 2003, the National Academy concluded that the vision of a hydrogen economy is based on two expectations:
• Domestic production of H2 can be affordable and environmentally benign
• H2 applications can be competitive in the market with alternatives
DOE Year 2030 Vision of Pathways to Hydrogen Production and Use
PhotovoltaicSolar thermal or biomass
Wind or OTEC
Fossil fuels
Renewable sourcesNuclear
Hydrogen
Electricity
Electrolysis of water
Fuel cell
ElectricityCombustion
Applications
Thermolysis of water
1
2
3
Chemical Conversion
Comparison of Electrolysis with Thermochemical Hydrogen Production
Primary Energy Source e.g. Fission, Fusion,
Solar
H2
O2
H2
O2
Heat Engine
Water Electrolysis
Heat Rejection
Heat
Heat
Heat
Rejection
Electricity
Thermochemical Process
Water
Water
Two Hydrogen Production Options
Reforming of H2 rich fossil fuel such as natural gas (CH4). Well developed chemical technology, efficient and inexpensive.
Electrolysis of water (H2O) separation of hydrogen by means of electric current. Well developed technology, needs electric power. Cost is three times that of reforming. Could use renewable source.
CH4 + 2H2O CO2 + 4H2
H2O H2 + ½ O2
Producing Electricity with Fuel Cell
Electrolysis
Fuel cell
Electricity
Hydrogen
Electricity
Present technology Advanced Technology
2.9 kWh 1.9 kWh
70% efficient 80% efficient
50% efficient 65% efficient
1 kWh 1kWh
Diagram of a Lead-Acid Cell
1800 Alessandra Volta describes first operating battery. Anode (negative pole) releases electrons which pass through an external circuit to the cathode, (positive pole). Poles are immersed in an electrolyte.
Hydrogen-Oxygen Fuel Cell
Discovered by William Grove in 1839
Fuel Cells of Current Technical Interest
Type AbbreviationOperating
Temperature
Polymer electrolyte fuel cell
PEFC 80ºC
Alkaline fuel cell AFC 100ºC
Phosphoric acid fuel cell PAFC 200ºC
Molten carbonate fuel cell
MCFC 650ºC
Solid oxide fuel cell SOFC 1000ºC
Well-to-Electric Grid Efficiency for Direct NG and Steam Reformed
Hydrogen Paths
Natural Gas,
%
S.R. Hydrogen, %
Production 95 95
Conversion to H2 n/a 78
Distribution (with H2 compression)
95 92
Conversion to electricity (Turbine or
Fuel Cell)
55 50
Overall Efficiency 50 34
Efficiency of Direct Solar PV and PV – Hydrogen Path to Electricity
Direct PV,
%
PV-Hydrogen,
%Solar Conversion to
Electricity15 15
Electrolysis to H2 n/a 78
Distribution (with H2 compression)
n/a 92
Fuel Cell to electricity n/a 50
Distribution 95 n/a
Overall Efficiency 14 5
Well-to-Electric Grid Efficiency for Direct Nuclear and Nuclear - H2 Paths
Nuclear,
%
Hydrogen,
%Production 90 90
Conversion to Electricity
36 36
Electrolysis to H2 n/a 78
Distribution (with H2 compression)
95 92
Fuel Cell for H2 to electricity
n/a 50
Overall Efficiency 31 12
HydricityIdaho National Laboratory
AC Electricity-H2-AC Electricity Loopreturns only 1/4th of the original AC Electricity
Comparison of Energy CarriersComparison of Energy Carriers
NowNow LimitLimit
Electrolytic Generation of HElectrolytic Generation of H22 7474 8585
CompressionCompression 9292 9292
Fuel Cell Conversion to ElectricityFuel Cell Conversion to Electricity 6060 7070
Overall EfficiencyOverall Efficiency 4040 5555
Hydrogen Efficiency (%)
Electricity
Storage (CAES, PWS, Battery) 75-80 85
Transmission Loss per 100 km
H2 Friction Loss in a Pipeline 0.8
Electric Transmission Loss 0.6
Compressed Air Electricity Storage System (CAES)
Conclusion• Unless future R&D can demonstrate economical
and safe production of hydrogen direct uses of fossil sources, nuclear fuel or renewable technologies are more efficient than using hydrogen by any currently available pathway to generate heat and electricity
• For the foreseeable future conservation in buildings and industry, increase efficiency and use of renewables in electricity production, synthetic fuels and improved mileage in transportation offer a more secure energy future than the hydrogen economy.
Transportation Crisis
• 97% of U.S. ground transportation is petroleum based, and in 2003, 53% of the oil consumed was imported.
• After housing, transportation is the largest budget item for the average U.S. household, larger than food or healthcare.
• Urban sprawl and lack of public transport make automobiles a necessity in the USA
Brief History of Electric Vehicles
1900 4200 Automobiles were sold– 40% were steam
powered– 38% were electric
powered– 22% were gasoline
powered1905
Electric Vehicle with Edison Battery wins 1000 mile endurance run
• 1990 California low Emission Vehicle Program (LEV) mandates that al least 2% of vehicles sold by each automaker have zero tailpipe emission by year 1998.
• 1991 – 1998 Automakers tested and promoted EVs, state agencies bought EVs and alternative fuel vehicles.
1999 – 2000 CARB removes EV mandate and automakers stop production of EVs.
Learn from the mistakes of Learn from the mistakes of others. You won’t live long others. You won’t live long enough to make them all enough to make them all
yourself.yourself.
Yogi BerraYogi Berra
Well-to-Wheel Efficiency Analysis
Feedstock Production
Feedstock T & S
Fuel Production
Fuel T & S & D
Vehicle Operations
Ground transportation technology options
• Electric Vehicles (EVs)
• Hybrid Electric Vehicles (HEVs)
• Fuel Cell Vehicles (FCVs)
• High Efficiency Diesel Vehicles
• Alternative Fuel Vehicles (AFVs)
• Public Transportation
• Telecommuting
• Intelligent Transportation Systems (ITS)
Well-to-Wheel Efficiency of Transportation Technologies
Vehicle DriveTechnology
FuelWell-to Wheel
Efficiency, %
Hybrid SI Natural gas (NG) 32
Hybrid Diesel Natural gas + Fischer Tropsch (FT) 32
Fuel cell + electric motor Hydrogen from NG 27
Hybrid SI Hydrogen from NG 22
Conventional diesel Natural gas + FT 22
Battery + electric motor Electricity from natural gas combined cycle
21
Conventional SI Natural gas 19
Fuel cell + electric motor Methanol 16
Conventional SI Hydrogen from NG 14
Fuel cell + electric motor Hydrogen (Electrolysis)
13
Well-to-Wheel Efficiency of Fuel-Cell Well-to-Wheel Efficiency of Fuel-Cell Vehicle with Hydrogen Produced by Vehicle with Hydrogen Produced by ElectrolysisElectrolysis
• NG Feedstock Production Efficiency NG Feedstock Production Efficiency 95% 95%• Conversion Efficiency (NG to electricity) Conversion Efficiency (NG to electricity)
55%55%• Electrolysis Efficiency (electricity to HElectrolysis Efficiency (electricity to H22) )
63%63%• Storage and TransmissionStorage and Transmission 97% 97%• Compression EfficiencyCompression Efficiency 87% 87%• Overall Efficiency of Fuel ProductionOverall Efficiency of Fuel Production 30% 30%• Total Fuel-Cell Well-to-Wheel Efficiency:Total Fuel-Cell Well-to-Wheel Efficiency:
(0.28 x 0.445 x 1.1 x 0.9)(0.28 x 0.445 x 1.1 x 0.9) 13% 13%
Nuclear Hydrogen Fuel Costsa Transportation Consumer
Three Times More Than Nuclear Electricity
Using 3-3.5 ¢/kWh as a placeholder price (note: being associated with AP1000-Rankine and claimed by VHTGR-Brayton).
Hydrogen Infrastructure Cost(Transportation Technology Center of Argonne National Laboratory)
• Assuming a fuel economy improvement for hydrogen FCV to 2.5 times of current conventional vehicles, (i.e. about 50 mpg) and a market penetration of 2% HFCV in 2020 and 12% in 2030, the cost is:– $60 billion in 2020– ~$170 billion in 2030
• If 40% of fleet is to be HFCV in 2030, minimum cost is $320 billion, but may be as high as $600 billion.
Making predictions is tricky; especially about the future.
-Yogi Berra
Hydrogen is the Fuel of the Future
• And it will always remain so…
EpilogueEpilogue
Are there alternatives to a Hydrogen Are there alternatives to a Hydrogen Economy?Economy?
Stopping population growth is a Stopping population growth is a necessary condition for the success of necessary condition for the success of any proposed long range energy policy.any proposed long range energy policy.
World Oil Production per Capita vs. Time
Electricity Generation
• Coal-fired Power Plants with CO2 SequestrationCost: 5-7 c/kwh1
• Nuclear Power Plants with Safe Long Term StorageCost: ~6-8 c/kwh1
• Solar Thermal Power Plants with Sensible Heat StorageCost: 5-9 c/kwh1
• Wind Turbines with Compressed Air StorageCost: 4-8 c/kwh2
Ref. 1 Sustainable Energy by J.W. Tester et al. MIT Press 2005Ref. 2 Estimates from Colorado PUC Hearing by Personal Communications
TransportationTransportation
Plug-in Hybrid Electric VehiclesPlug-in Hybrid Electric VehiclesWith Metal-Hydride or Lithium Ion Batteries and Off-With Metal-Hydride or Lithium Ion Batteries and Off-
Peak Charging. Peak Charging. Levelized Cost Effective over 8-10 years.Levelized Cost Effective over 8-10 years.
(EPRI Study, 2003 ~70-80 gpm)(EPRI Study, 2003 ~70-80 gpm) Synthetic FuelsSynthetic Fuels
a)a) Diesel by Fischer-Tropsch Process from Coal Diesel by Fischer-Tropsch Process from Coal (SASOL)(SASOL)
b)b) Ethanol from Sugar Cane, Cost-effective in BrazilEthanol from Sugar Cane, Cost-effective in Brazilc)c) Ethanol from Switschgrass, Proposed by President Ethanol from Switschgrass, Proposed by President
George W. Bush, needs more R&D.George W. Bush, needs more R&D.
A Final Word of CautionA Final Word of Caution
Anyone who believes that one Anyone who believes that one can have exponential can have exponential growth in a finite world is growth in a finite world is either a madman or an either a madman or an economist.economist.
Kenneth BouldingKenneth Boulding