>> I did that for my Prius, and discovered that it costs about 5c a mile
>> for fuel. Remember, 100% of the Prius propulsion energy comes from
>> gasoline. There is no other source whatsoever, but the hybrid system
>> permits the use of a highly efficient ICE that has poor acceleration
>> characteristics, supported by an electric motor which has maximum torque
>> at zero rpm. The Volt, on the other hand, can be 100% plug-in for
>> average days (for me), with the ICE entering the equation only when I
>> drive further than, say, 40 miles between charges.
>>
>> If GM's Volt project delivers its promoted configuration, it will cost
>> ME less than 3c per mile.
>
> psssst--you have to acquire (and depreciate) the vehicle first.
And replacement batteries. They don't last that long. All that cadmium, lithium, mercury, nickel or whatever they use. A $4000 battery pack pays for a lot of gasoline.
You are correct, depreciation is part of the cost of ownership, in the end the financial costs are about TCO including repairs, batteries, gasoline, tune-ups, cost of electricity, insurance etc. Not simply a flat mpg calculation. Even costs in renting alternative vehicles should be included if your lifestyle needs it (towing/hauling).
It is why GM and others need a full line of vehciles, as one size does not fit all.