Introduction
Conclusions
Storing and Moving Hydrogen
West Sacramento Hydrogen Fueling Station
Source: California Fuel Cell Partnership
Those promoting the use of hydrogen as an energy carrier generally point to its characteristics in combustion: clean emissions and high energy content. Skeptics are more likely to point out that hydrogen’s physical characteristics make it very difficult to handle. As the lightest element, molecular hydrogen (H2) has a molar mass of only 2.01g/mol. Thus, while the amount of hydrogen required to power a small, efficient fuel cell car for approximately 250 miles is only 4kg, that same 4kg of gaseous hydrogen at room temperature and pressure would occupy 45m^3! [1]
Moreover, hydrogen’s weak intermolecular forces allow it to permeate many common materials and give it a boiling temperature of only 21K at atmospheric pressure, making the technological challenges to dealing with hydrogen in its liquid form very significant.
It is not surprising then, that of the three major challenges that experts cite regarding the use of hydrogen as a hydrocarbon replacement, developing storage tanks for small and mobile uses and designing a distributive network make up two. (The other is developing effective and practical fuel cells to burn hydrogen cleanly and efficiently.) [2]
Traditional technologies that deal with fuel storage and networks have had mixed results when applied to hydrogen applications. For example, high-pressure canisters remain the most common method for hydrogen storage and hydrogen pipelines can transport the gas much like natural gas. But these technologies are often only marginally effective and may someday be replaced with a host of new ideas that are under development. On the other hand, the revolutionary advances needed for these alternative technologies to be successful may not materialize and hydrogen may remain as an alternative to hydrocarbons rather than a replacement.
This section explores the possibilities for hydrogen storage and usage in the real world economy. Click on one of the links at left to learn more about a subtopic.
Sources:
[1] Schlapbach, L. and Andreas Zuttel (2001). "Hydrogen-Storage Materials for Mobile Applications." Nature 414: 353-358.
Jensen, Marc W. and Marc Ross (2000). “The Ultimate Challenge: Developing an Infrastrcuture for Fuel Cell Vehicles.” Environment 41: 10-22.