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by calibration263 3237 days ago
Your article states 87.7% efficiency in gasoline refining.

Energy density of gasoline is 34.2 MJ/L: https://en.wikipedia.org/wiki/Energy_density

This means there was 4.8 MJ of energy spent to create 1L of gasoline. The 70kWh(250MJ) tesla is reported to have 390KM range. 4.8 MJ would be 1.92% of the range, or about 7.5km. The Mazda 3 has a combined fuel economy rating of 33 MPG, which is about 14KPL.

As far s I can tell, your statement that an EV can go further on the power needed to refine a gallon of gas, than an ICE car can drive is off by a factor of almost two.

That said, arguing an electric car can go a certain distance based on inefficiencies of another unrelated process is not a very meaningful argument. You need to look at the efficiencies and CO2 produced for drilling/transporting/refining/burning gas vs producing/transmitting/storing/using electric power, and probably the costs of dealing with peak loads vs non-peak loads, and even then the argument is heavily weighted on where your power comes from.

1 comments

Well, the US average for fuel efficiency is 25, not 33. And the Model S is one of the least efficient EVs, for worse than the average. Adjust both those numbers in the right directions and your math lines up with my point nicely.