Well... I'd like to answer the initial post from a Spanish point of view.
Cost of gas: 1.40 €/litre. (Aprox 6USD/gallon)
Cost of electricity at night: 0,04 € kW. (0,047usd)
Anual distance traveled: circa 35000km (21700 miles).
Though Tesla cars are way more expensive than in the USA, the...