[aerohead]

In the not too distant past, hydrogen storage was an issue.
As the 'smallest' atom, hydrogen was capable of escaping through the walls of any vessel it was stored in.
There was a promising carbon nano-structure which was capable of 'holding' the gas, but to get it back out required heating the vessel, adding entropy to the 'system' and reducing its market viability.
I believe that California's 'Hydrogen Highway' ( Gov. Arnold Shwarzenegger ) relies on natural gas as the feed stock.
Rather than attempt to store significant amounts of gas onsite, SHELL and TrueZero equipment harvests the gas from a PP&G natural gas pipeline, then a high-pressure compressor forces it into the Toyota or Honda fuel cell at 700-bar, and $45-$50 a fill.
MOTOR TREND's Toyota Mirai has averaged 67.8-mpg over 13,822-miles.