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by pkulak 3236 days ago
https://en.wikipedia.org/wiki/The_long_tailpipe#Criticism

The biggest nail in the coffin of the long tailpipe fallacy is that you can drive an EV farther on the power needed to refine a gallon of gas than you can drive a ICE car on that same gallon. So, even if you built a gasoline engine that had absolutely no emissions, and oil bubbled up into crude lakes right next to every refinery, EVs would still be more efficient.

2 comments

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.

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.
Refining gasoline seems to be ~88% efficient per your source. While this isn't negligible, it hardly changes the argument.
Sure. And an EV can drive ~25 miles on the energy in that 12%.