Even though hydrogen in a theoretical sense is more efficient, practically, using hydrogen as an automotive fuel entails multiple technological difficulties that to date have not been satisfactorily resolved:
1. Complex distribution system (using hydrogen requires a totally new and costly distribution
infrastructure.)
2. The existing technologies for storing hydrogen on board - namely, high-pressure compression
or liquefaction - are complex, expensive, and the high energy requirements of either of these
processes will eliminate the theoretical efficiency advantage of hydrogen over methanol.
There are however future promising technologies for on board storage of hydrogen that could
resolve these issues, among them graphite fibers, carbon nanotubes, and metal hybrids. Once
these technologies become available, they could gradually be incorporated into the market.
3. Hydrogen is extremely flammable. The smallest molecule of any matter, hydrogen has a tendency to leak -
thus exacerbating the flammability issue. While this is avoidable in laboratory conditions,
it becomes much more complex when common vehicle maintenance is involved. To avoid this
problem high safety fittings for the hydrogen system would have to be developed.
More information:The Future of the Hydrogen Economy: Bright or BleakThe hydrogen economy,fuel cells, and electric carsComparing Hydrogen and Electricity for Transmission, Storage and TransportationHydrogen or electricity? A nuclear fork in the road
