Re:Hydrogen: Pros and Cons (Score 1)

One problem is that even liquid hydrogen is very light (very low density) and so requires very large tankage

The article talks about liquid hydrogen but if this ever gets to the engineering stage I doubt that they would use it. Cryogenic hydrogen is difficult and expensive to store, dangerous to handle, and still really not dense enough for aircraft.

There are other solutions however: a variety of liquids are safe sources of hydrogen and can be reformed into hydrogen quickly. For instance, Millenium Cell has information on their process, quote:

In the process, the energy potential of hydrogen is carried in the chemical bonds of sodium borohydride, which in the presence of a particular catalyst either releases hydrogen or produces electricity. The primary input components of the reaction are water and sodium borohydride, a derivative of borax.

In this case the "waste" can be kept and recycled back into sodium borohydride.I menion Millenium because I'm familiar with them but there are undoubrable other solution in the works. Various processes using hydrides and or nanotube storage system show potential. If you type "hydrogen storage" in the search box at www.ingenta.com you can get a good idea of the range of research.