2. Overview
Uses of hydrogen
Hydrogen economy
Hydrogen production
Challenges to a hydrogen economy
Storage of hydrogen
3. Uses of Hydrogen
Haber Process – Roughly 50% of hydrogen use.
Producing ammonia for fertilizers
Hydrocracking – Roughly 50% of hydrogen use.
Cracking – complex organics to simpler molecules
Converting heavy petroleum fractions into lighter ones
Hydrogen Economy
Hydrogen as an energy carrier, not a source
Must be generated
Expanding enterprise
4. Hydrogen Economy
John Bockris – 1970
A solution to the pollution emission from hydrocarbon
fuels
One pound of hydrogen holds 52,000 BTU, three times
the energy of a pound of gasoline
Many issues
Storage
Purity 99.999% for fuel cells
Costs
6. Methods of Hydrogen Production
Graphic: http://www.fsec.ucf.edu/en/consumer/hydrogen/basics/images/HydrogenProductionPaths.gif
7. Methods of Hydrogen Production
Steam Reformation of Natural Gas
Cheapest method
CH4 + H2O → CO + 3H2 at 700 – 1100 °C in the presence
of a metal-based catalyst.
CO + H2O → CO2 + H2
Still emits pollution as CO2
Carbon capture
8. Methods of Hydrogen Production
Electrolysis
2H2O + energy → 2H2 + O2
Uses electric current to split water; many methods.
High-pressure, high-temperature, biocatalyst, thermal,
solar, etc.
Gasification
Coal or Biomass converted into gaseous components by
heat, under pressure, in the presence of steam.
Carbon capture
9. Methods of Hydrogen Production
Kværner-process
Carbon Black and Hydrogen (CB&H) method
Produces hydrogen and carbon black from
hydrocarbons
Energy-efficient, pure 100% carbon and hydrogen.
Biological
Bacteria consume water in light or
without light to produce hydrogen
as a byproduct.
Graphic: http://upload.wikimedia.org/wikipedia/commons/2/21/Algae_hydrogen_production.jpg
10. Methods of Hydrogen Production
Renewable Liquid Reforming
Biomass used to make biofuels can be reacted with high-
temperature steam to produce hydrogen.
Global production (2006):
48% from natural gas
30% from oil
18% from coal;
Water electrolysis accounts for only 4%.
11. Main Challenges to a Hydrogen
Economy
Cost reduction
Transportation technology
Production technology
Conversion processes over other sources of energy
Storage
Infrastructure
12. Storage of Hydrogen
One of the foremost challenges to the hydrogen
economy
Compressed gas in high-pressure tanks
Liquid in tanks (-253°C)
Solid by absorbing or reacting with metals
Issues:
Operating pressure and temperature
Life span of the storage material
High energy content compared to weight, low energy
content compared to volume, especially for gas.
14. Infrastructure
Pipeline transport
Expensive, but still cheapest.
Hydrogen stations
Hydrogen embrittlement
Typical natural gas lines require coatings or replacement
Idea of on-site applications
Explosion leaks
Hydrogen-oxygen flames in UV range
Odorless
15. References
References:
1. Hydrogen Economy - Wikipedia, the free encyclopedia.
http://en.wikipedia.org/wiki/Hydrogen_economy (accessed 26
Feb 2012).
2. Hydrogen Technologies.
http://www.interstatetraveler.us/Reference-
Bibliography/Bellona-HydrogenReport.html (accessed 26 Feb
2012).
3. Hydrogen Production.
http://www.hydrogen.energy.gov/pdfs/doe_h2_production.pdf
(accessed 26 Feb 2012).
4. Hydrogen.
http://www.fsec.ucf.edu/en/consumer/hydrogen/index.htm
(accessed 26 Feb 2012).