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Comment by chongli | Hacker News Reader

For the hundreds of Nikola trips with an average speed of 60 mph, the actual MPGe was about 102. Once you get up to an 75 MPH average trip speed, the MPGe drops to 94. And by 80 MPH the MPGe drops to 77. (avg over all Tesla types)

That makes total sense. What I think most people don’t realize is that power is force times velocity and the force you need to apply to maintain a given velocity is equal to the friction plus the drag. Unfortunately, drag increases with the square of the velocity and so when you go faster you need way more power. This translates directly into increased battery drain for an EV.

The problem may be further exacerbated by the greatly increased mass of an electric vehicle and the potential for the batteries to overheat.

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This is why some governments raise speed limits. Faster traffic -> more energy required per mile -> more gas consumed -> more gas tax revenue

Or it’s because it’s politically popular to raise speed limits since they usually raise them to the speed that is almost, but still below, the speed that everybody is already driving at currently.

Also in the US the AAA heavily invests in lobbying for higher speed limits every year. The AAA isn't quite the villains in American politics that the NRA are (ETA: or at least, have become), but they are historically close. It's easy to forget that AAA was founded to fight speed limits in the first place.

"AAA was founded to fight speed limits in the first place"

Wow never knew this is true, any sources where I can read more about this?

I'll admit it is something of an uncharitable view. The given reason AAA was founded was to improve the "quality" of roads in the country. One of the qualities that was seen as lacking at the time was the inability to use anything close to the top speed of cars due to road hazards and pedestrians. It's related to why AAA was the first car racing body in the country, overseeing for instance early versions of the Indianapolis 500 (though it divested racing later on).

(ETA: The search term I was forgetting was "jaywalking", because AAA was instrumental in the creation of jaywalking as a crime, related to the goals of allowing faster car travel versus speed limits. https://www.salon.com/2015/08/20/the_secret_history_of_jaywa...)

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