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Fallacies of a Hydrogen Economy. 2006 Byron Short Lecture University of Texas at Austin. Dr. Frank Kreith.
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2006 Byron Short LectureUniversity of Texas at Austin Dr. Frank Kreith
“Let us set as our national goal in the spirit of Apollo, with the determination of the Manhattan Project, that by the end of this decade we will have developed the potential to meet our own energy needs without depending on any foreign energy source.” President 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 of Society in 21st Century • Heat • Fuel • Electricity
Energy Projection • 1956 Edward Teller “Nuclear will be too cheap to meter.” • 1973 President Nixon “By 1980, we will be self sufficient and not need foreign energy.” • 1978 President Carter “In 20 years, 20% of our energy will be from solar.” • 1980 President Reagan “Alaska has a greater oil reserve than Saudi Arabia.” • 2003 President Bush “The first car driven by a child born today could be 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
Fossil fuels Nuclear Renewable sources Photovoltaic Solar thermal or biomass Wind or OTEC Electricity 3 1 2 Chemical Conversion Thermolysis of water Electrolysisof water Hydrogen Fuel cell Combustion Electricity Applications DOE Year 2030 Vision of Pathways to Hydrogen Production and Use
Heat Engine Water Electrolysis Heat Electricity Heat Rejection Thermochemical Process Heat Water Water Heat Rejection Comparison of Electrolysis with Thermochemical Hydrogen Production H2 O2 Primary Energy Source e.g. Fission, Fusion, Solar H2 O2
CH4 + 2H2O CO2 + 4H2 H2O H2 + ½ O2 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.
Electricity Electrolysis Hydrogen Fuel cell Electricity Producing Electricity with Fuel Cell
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.
Discovered by William Grove in 1839 Hydrogen-Oxygen Fuel Cell
Well-to-Electric Grid Efficiency for Direct NG and Steam Reformed Hydrogen Paths
Efficiency of Direct Solar PV and PV – Hydrogen Path to Electricity
Well-to-Electric Grid Efficiency for Direct Nuclear and Nuclear - H2 Paths
HydricityIdaho National Laboratory AC Electricity-H2-AC Electricity Loopreturns only 1/4th of the original AC Electricity
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 powered 1905 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 others. You won’t live long enough to make them all yourself.Yogi Berra
Feedstock Production Feedstock T & S Fuel Production Fuel T & S & D Vehicle Operations Well-to-Wheel Efficiency Analysis
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 Fuel-Cell Vehicle with Hydrogen Produced by Electrolysis • NG Feedstock Production Efficiency 95% • Conversion Efficiency (NG to electricity) 55% • Electrolysis Efficiency (electricity to H2) 63% • Storage and Transmission 97% • Compression Efficiency 87% • Overall Efficiency of Fuel Production 30% • Total Fuel-Cell Well-to-Wheel Efficiency: (0.28 x 0.445 x 1.1 x 0.9) 13%
Nuclear Hydrogen Fuel Costsa Transportation ConsumerThree 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…
Epilogue • Are there alternatives to a Hydrogen Economy?
Stopping population growth is a necessary condition for the success of any proposed long range energy policy.
Electricity Generation • Coal-fired Power Plants with CO2 Sequestration Cost: 5-7 c/kwh1 • Nuclear Power Plants with Safe Long Term Storage Cost: ~6-8 c/kwh1 • Solar Thermal Power Plants with Sensible Heat Storage Cost: 5-9 c/kwh1 • Wind Turbines with Compressed Air Storage Cost: 4-8 c/kwh2 Ref. 1 Sustainable Energy by J.W. Tester et al. MIT Press 2005 Ref. 2 Estimates from Colorado PUC Hearing by Personal Communications
Transportation • Plug-in Hybrid Electric Vehicles With Metal-Hydride or Lithium Ion Batteries and Off-Peak Charging. Levelized Cost Effective over 8-10 years. (EPRI Study, 2003 ~70-80 gpm) • Synthetic Fuels • Diesel by Fischer-Tropsch Process from Coal (SASOL) • Ethanol from Sugar Cane, Cost-effective in Brazil • Ethanol from Switschgrass, Proposed by President George W. Bush, needs more R&D.
A Final Word of Caution Anyone who believes that one can have exponential growth in a finite world is either a madman or an economist. Kenneth Boulding