Hydrogen refueling stations would be located every twenty miles and would cost hundreds of millions to implement
"Gov. Arnold Schwarzenegger wants to speed California drivers to a future in which the most common element in the universe -- hydrogen -- will power their cars instead of petroleum. To wean a gas-guzzling nation from a finite supply of fossil fuels, the governor has thrown his weight behind "Hydrogen Highways," an ambitious but costly plan to build a statewide network of 200 hydrogen filling stations by the end of the decade.
The investment is necessary, proponents say, because without refueling stations, automakers may not produce enough of the alternative cars and consumers will not buy them.
Stations would be located every 20 miles along major highways and interstates. Each station would cost $250,000 to $500,000, and the total expense could run into the hundreds of millions of dollars. The undertaking would be financed with a combination of public and private money.
EDIT
Because so few fuel cell cars have been built — about 60 are in service in California — they are costly, about $1 million apiece to produce today. Their range is limited to about 200 miles before refueling, much less than the range of a gasoline car. Increasing the range would require more fuel tanks, which would take up too much space in the vehicle, according to the Energy Department. The cars being road-tested in California were provided by the auto industry to universities, cities and public agencies."
EDIT
http://www.evworld.com/view.cfm?section=communique&newsid=4856