Looks for the first very contradictorily, that something becomes cheaper because of expensive oil. But a look on the propulsion concept clears up the paradox.
Plug in hybrid vehicles
The best from both worlds. From the electric car the cheap and with solar energy easy to produce fuel electric power. From the car with the comustion engine the fuel liquid at normal temperatures with high energy density and extrem fast refueling.
Combustion engine eliminates disadvatages of the electric car
long refueling - several hours charging the batteries
The electric engine eleminates the disatvantages of the combustion engine
High consumption after cold start
Sensless consumption standing at a traffic light
Wast of energy at deaccelerating
High consumption at low speeds in city traffic
This shows, as long as a plug in hybrid is used within the electric only range, it's much cheaper than a car with interal combustion engine.
Natural, all the additional technic for a plug in hybrid make a plug in hybrid more expensive than a conventional car. To expensive for cheap oil. But with more expensive oil, the borders of profitability are moving.