Overview Uses of hydrogen Hydrogen economy Hydrogen production Challenges to a hydrogen economy Storage of hydrogen
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
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
Methods of Hydrogen Production Graphic: http://www.fsec.ucf.edu/en/consumer/hydrogen/basics/images/HydrogenProductionPaths.gif
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
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
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
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%.
Main Challenges to a HydrogenEconomy Cost reduction Transportation technology Production technology Conversion processes over other sources of energy Storage Infrastructure
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.
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
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).