Also, please look at diesel-electric engines.
Same principles applies to the energy costs of an electric vehicle, they just happen to charge their batteries from a source other than onboard motor.
Also, at 12 cents a kilowatt hour, the costs are much less than how much petrol you'd use in an e90 over the same amount of miles. I think your math is off. As one reviewer stated, his 300 mile trip cost about 7 bucks. That same trip in an e90 will cost about 60.
2011 E90 / Premium Package / Stage 2 PPK / Performance Suspension