I like the idea of hydrogen as a transportation energy source.
A lot of people against hydrogen mention that you still need the energy to extract it from H2O or some other source. Much of this is from fossil fuel burning power plants. While initially it seems as if you are just putting in another step in the energy equation, one must realize one important difference.
The fossil fuels will be burned only at the power plants, thus the resulting pollution can be sequestered or disposed of in an environmental fashion. This includes CO2 sequestering which may be a viable technology should our government ever put the funds into it. Now compare this with burning fossil fuels in automobiles. In this case, you have large amounts of fossil fuels and all their associated nasty waste going into the environment practically unregulated. This, in my opinion is far worse than using fossil fuel at specific locations to produce clean fuel for all locations.
Utilizing H2 will also allow us to reduce overall CO2 emissions if we begin non-fossil fuel based energy programs. In my opinion nuclear energy is the best and most viable route. Solar is too expensive and inefficient. Wind has the same pitfalls, and hydro has issues as well as questionable production capacity.
Current nuclear technology in the United States results in needless amounts of long life waste. This is because we are basically burning U235 mixed with U238 instead of breeding new fuel. We also are not reprocessing our fuel. Fortunately, there has been a new approval by congress to work on a new UREX fuel processing program for the US. However, no funding has been appropriated to the research and departments for the development of such a program......
Anyways, over the long term, switching to a thorium (th-232)/U-233 based fuel cycle would drastically reduce waste and give us a very good long term solution. Currently, India is the only country to be using this process.
Sorry to get off topic...
Anyways, I think H2 would be a great solution for issues we see with transportation energy sources. However, we definitely need to upgrade and develop better primary energy sources if we intend to do so. In my opinion, nuclear energy is the most viable, cleanest route in the interim before newer energy methods are developed.