The Hydrogen Hoax
The science-based argument states how inefficient the hydrogen production process is, while also pointing out that there is no viable way of efficiently storing liquified hydrogen or compressed hydrogen. In fact, according to Zubrin, to store 20 kg of hydrogen (comparable to 20 gallons of gasoline), would require either a 70-gallon cryogenic tank, or a 162 gallon tank at 5,000 PSI tank - the compressed hydrogen gas tank along would weigh approximately 2,800 pounds (without the 20 kilograms of fuel); the cryogenic storage tank would be prone to failure due to the nature of cryogenic hydrogen, which causes metal fatigue and brittleness and 'boils off,' which could be a serious safety issue in confined quarters (such as parking garages).
The most important points he puts forth, however, are the inefficiency of burning hydrogen as compared to gasoline (hydrogen has a lower energy density); as well as the need to produce hydrogen - as 100% of the hydrogen on the planet earth is already bound up in chemical compounds... requiring enormous amounts of energy to free up the hydrogen from these bonds:
The spokesmen for the hydrogen hoax claim that hydrogen will be manufactured from water via electrolysis. It is certainly possible to make hydrogen this way, but it is very expensive—so much so, that only four percent of all hydrogen currently produced in the United States is produced in this manner. The rest is made by breaking down hydrocarbons, through processes like pyrolysis of natural gas or steam reforming of coal.
Dispensed in compressed gas cylinders to retail customers, the current price of commercial grade hydrogen is about $100 per kilogram. For comparison, a kilogram of hydrogen contains about the same amount of energy as a gallon of gasoline.
...then he gets down to the actual chemical reactions used commercially to change hydrocarbons to pure hydrogen, and the extra energy needed to compress or refrigeration to cryogenic temperatures - which could sap up to 40% of the original energy potential in the original hydrocarbons. As for hydrogen production via electrolysis - where would the energy come from? Pick your poison: coal or nuclear.