After a preselection for this 3 fuel sorts has to be evaluated which one is cheapest for the cars drivers in 20 years.
Electric power in abundance, lack of biomass and crude oil
The basic premise for the scenario: the photovoltaic world market is grown to over 100 Watt Peak per human and year. Over 600 GW photovoltaic is installed each year. The prognosis of the Energy Watch Group is took place, the oil production is below 50% from the current production.
Fuel hydrogen from electrolysis
At each of the 3 fuel sorts, hydrogen from electrolysis is a ruling element. The demand for fuel is much reduced, because Plug-in Hybrid cars drive 80% of all kms with electric power. Fuel is only needed for the 20% of travels outside the electric range.
Hydrogen without fuel cell
The fuel cell could fail to reach a price to be economic in a car. Maybe not enough advantage in efficiency to compensate the higher price with less consumption. As a range extender ICE internal combustion engines work with around 40% efficiency.
Example Chevrolet Volt
4 kg hydrogen converted to electric power with 40% efficiency are only 390 km range. So huge tanks, small range. On the other hand 44m³ methan for 1440km. Here it would be possible to remove the front pressure tank and put more batteries there, the hydrogen Volt has only half the batteries. The rear pressure tank should be enough for 800km range.