Hydrogen oxygen fuel, in the form of the hydrogen fuel cell vehicle, is already on the road as the Honda Clarity FCX. This is the very first vehicle of its type, and likely to remain so for some time, as other manufacturers are far behind in research and development where they're even pursuing the technology. Having hydrogen oxygen fuel available is fine, but how much will it cost the consumer to maintain and run a car on it?
The Honda Clarity FCX is only available on a 3-year lease, so it's impossible to judge a retail selling price for the car. That figure simply isn't available. As it stands, the consumer pays $600 per month for the lease. Unusually, this includes all service and maintenance, as well as collision insurance, a first for a vehicle. With most leases, all those extras are the responsibility of the person obtaining the lease.
Unlike most fuels, even alternative fuels, which are measured in gallons, hydrogen oxygen fuel is measured in kilograms. The owner fills up with hydrogen. Currently there are very few hydrogen filling stations, and these are all located in southern California, the only place where the car is sold. Honda is working on home filling stations for owners. Certainly, there will need to be a network of stations or home stations for the car to become viable.
The situation is similar to electric vehicles, where charge points are available in some areas, albeit few and far between, and the vehicles can also be charged at home. As of 2007, the price for hydrogen was in the region of $8 per kilogram, with a mileage of 60 miles per kilo. That's far more expensive than other alternative fuels, but it puts out zero emissions.
There's very little maintenance involved with a hydrogen oxygen fuel cell vehicle, because there's no internal combustion engine and far fewer moving parts. Tires will still need to be rotated and some basic servicing done, but the level is minimal. This is why it can be included in the lease price. With so little upkeep involved, the running costs of a hydrogen oxygen fuel car are low, outside the cost of actual fuel (which may diminish over time).
The quantities of the Honda Clarity FCX that are available are extremely limited. This is by design; these models function almost as commercial prototypes, giving engineers a chance to see how the car performs under extended use. There are less than 1,000 of them on the road (no exact figure has been given) and if sold outright, the price would certainly be prohibitive to all but the extremely wealthy.
The numbers will remained restricted for the foreseeable future as the company improves its hydrogen oxygen fuel cell vehicles. Until it's feasible to obtain fuel anywhere and everywhere, this won't be viable as a commercial vehicle. Given the amount invested in research for this fuel by the government, however, its long-term future does seem to be assured.