Download - A Hydrogen Economy
A Hydrogen Economy
Agenda
• A Hydrogen Vision of the Future
• Hydrogen Systems
• Producing Hydrogen
• Storing and Transporting Hydrogen
• Hydrogen Fueled Transport
• Problems with Hydrogen
• The Promise of Hydrogen
• Hydrogen Summary
A Vision of a Hydrogen Future
"I believe that water will one day be employed as fuel, that hydrogen and oxygen which constitute it, used singly or together, will furnish an inexhaustible source of heat and light, of an intensity of which coal is not capable. I believe then that when the deposits of coal are exhausted, we shall heat and warm ourselves with water. Water will be the coal of the future."
Jules Vernes (1870) L´île mystérieuse
Hydrogen Economy Schematic
Hydrogen Economy in Hong Kong
http://www.gii.com.hk/eng/clean_energy.htm
New Busses in China
Hydrogen Fueling Station
Hydrogen Systems
Hydrogen Production Cycle
Crabtree et al., “The Hydrogen Economy,” Physics Today, Dec 2004
Operating the Hydrogen Economy
Bossel et al., The Future of the Hydrogen Economy: Bright or Bleak?, Oct 28, 2004http://www.oilcrash.com/articles/h2_eco.htm
Hydrogen Economy Supply Chain
Hydrogen Pathways
http://www.ch2bc.org/index2.htm
Advantages of a Hydrogen Economy
• Waste product of burning H2 is water
• Elimination of fossil fuel pollution
• Elimination of greenhouse gases
• Elimination of economic dependence
• Distributed production
http://www.howstuffworks.com/hydrogen-economy.htm
Issues with Hydrogen
• Not widely available on planet earth
• Usually chemically combined in water or fossil fuels (must be separated)
• Fossil fuel sources contribute to pollution and greenhouse gases
• Electrolysis requires prodigious amounts of energy
Technological Questions
• Where does hydrogen come from?
• How is it transported?
• How is it distributed?
• How is it stored?
http://www.howstuffworks.com/hydrogen-economy.htm
Producing Hydrogen
Current Hydrogen Production
•Current hydrogen production
•48% natural gas•30% oil•18% coal• 4% electrolysis
•Global Production•50 million tonnes / yr•Growing 10% / yr
•US Production•11 million tonnes / yr
How is Hydrogen Produced?
• Reforming fossil fuels• Heat hydrocarbons with steam• Produce H2 and CO
• Electrolysis of water• Use electricity to split water into O2 and H2
• High Temperature Electrolysis• Experimental
• Biological processes• Very common in nature• Experimental in laboratories
http://www.howstuffworks.com/hydrogen-economy.htm
Steam Reforming
• From any hydrocarbon• Natural gas typically used
• Water (steam) and hydrocarbon mixed at high temperature (700–1100 °C)• Steam (H2O) reacts with methane (CH4) • CH4 + H2O → CO + 3 H2 - 191.7 kJ/mol
• The thermodynamic efficiency comparable to (or worse than) an internal combustion engine• Difficult to motivate investment in
technology
Electrolysis of Water (H2O)
http://www.gm.com/company/gmability/edu_k-12/9-12/fc_energy/make_your_own_hydrogen_results.html
Electrolysis of Water
http://hyperphysics.phy-astr.gsu.edu/hbase/thermo/electrol.html
Renewable Energy for Electrolysis
http://www.howstuffworks.com/hydrogen-economy4.htm
Biomass Electrolysis Module
http://www.nrel.gov/hydrogen/photos.html
High Temperature Electrolysis
• Electrolysis at high temperatures
• Use less energy to split water
http://en.wikipedia.org/wiki/Hydrogen_economy
Biological H2 Creation
•Nature has very simple methods to split water
•Scientists are working to mimic these processes in the lab; then commercially
Crabtree et al., “The Hydrogen Economy,” Physics Today, Dec 2004
Storing & Transporting Hydrogen
Hydrogen Storage
• Storage a major difficulty with hydrogen• H2 has low energy density per volume
• Requires large tanks to store
• H2 can be compressed to reduce volume• Requires heavy, strong tanks
• H2 can be liquefied to reduce volume• Boils at -423 °F (cryogenic)• Requires heavily insulated, expensive tanks
• Both compression and liquefaction require a lot of energy
Ammonia Storage
• H2 can be stored as ammonia (NH3)
• Exceptionally high hydrogen densities
• Ammonia very common chemical• Large infrastructure already exists
• Easily reformed to produce hydrogen• No harmful waste
• BUT• Ammonia production is energy intensive• Ammonia is a toxic gas
Metal Hydride Storage
• Metal hydrides can carry hydrogen• Boron, lithium, sodium• Good energy density, but worse than gas
• Volumes much larger than gasoline• Three times more volume• Four times heavier
• Hydrides can react violently with water• Leading contenders
• Sodium Borohydride• Lithium Aluminum Hydride• Ammonia Borane
Alkali Prod. Energy vs. Instrinsic Energy
Energy needed to produce alkali metal hydrides relative to the energy content of the liberated hydrogen.
Bossel et al., The Future of the Hydrogen Economy: Bright or Bleak?, Oct 28, 2004http://www.oilcrash.com/articles/h2_eco.htm
Transporting Hydrogen
Storing & Transporting Hydrogen
• Store and Transport as a Gas• Bulky gas
• Compressing H2 requires energy
• Compressed H2 has far less energy than the same volume of gasoline
• Store and Transport as a Solid• Sodium Borohydride• Calcium Hydride• Lithium Hydride• Sodium Hydride
http://www.howstuffworks.com/hydrogen-economy.htm
Hydrogen Fueled Transport
Hydrogen-Powered Autos
Hydrogen-Powered Autos
http://planetforlife.com/h2/h2vehicle.html
Hydrogen-Powered Trucks
http://planetforlife.com/h2/h2vehicle.html
Hydrogen-Powered Aircraft
http://aix.meng.auth.gr/lhtee/projects/cryoplane/
Hydrogen powered passenger aircraft with cryogenic tanks along spine of fuselage. Hydrogen fuel requires about 4 times the volume of standard jet fuel (kerosene).
http://planetforlife.com/h2/h2vehicle.html
Hydrogen-Powered Rockets
http://planetforlife.com/h2/h2vehicle.html
Implications of Hydrogen Transport
Weight of fuel
Weight of steel tank
Weight of carbon fiber tank
Volume of tank contents
Volume of tank
Typical 18 wheel truck (diesel)
1175 lb (small) NA 22.5 feet3 24.0 feet3
Typical sedan (gasoline)
108 lb (small) NA 2.25 feet3 2.5 feet3
Truck converted to ICE hydrogen
313 lb 31,300 lb 6,960 lb 67.5 feet3 157 feet3
Sedan converted to hydrogen fuel cell
17.4 lb 1740 lb 387 lb 4 feet3 9 feet3
http://planetforlife.com/h2/h2swiss.html
The Promise of Hydrogen
UNIDO-ICHET Projection
http://www.unido-ichet.org/ICHET-transition.php
UNITED NATIONS INDUSTRIAL DEVELOPMENT ORGANIZATIONINTERNATIONAL CENTRE FOR HYDROGEN ENERGY TECHNOLOGIES
The Iceland Example
• Iceland committed to be the first hydrogen economy• 2050 goal
• Will use geothermal resources to create hydrogen• Power autos, buses, and fishing fleet with hydrogen
http://en.wikipedia.org/wiki/Hydrogen_economy
The Hydrogen NanoHorn
• If this is developed, we will have a hydrogen economy.
• Aleutian Island wind turbines to generate hydrogen via electrolysis