this post was submitted on 06 Jan 2024
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Tesla Cybertruck gets less than 80% of advertised range in YouTuber’s test::A YouTuber took Tesla’s Cybertruck on a ride to see if it can actually hit its advertised 320-mile range, only to find out that its could only reach 79% of the target. When YouTuber Kyle Conn…

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[–] [email protected] 36 points 10 months ago (3 children)

Regenerative braking isn't magical. It doesn't add range. It reduces range lost by stopping. Conservation of energy is still a thing.

If you were to drive any speed uninterrupted until the vehicle died, then attempted the same drive with stops every mile, the vehicle wouldn't make it to the end.

[–] [email protected] 2 points 10 months ago

This is true, but it's neglecting one variable that does complicate the math slightly. There is greater air resistance at highway speeds. IIRC at 60mph 50% of your power is lost due to the air resistance.

So yes, if we lock the speed to a fixed value and compare them, then regenerative of course doesn't increase the range more than not stopping at all. But that's the nuanced gap in the discussion where misunderstanding is going to reside. That's why you two are on different pages. Someone is assuming equal air resistance (speed), and someone is assuming a comparison of average city miles vs highway miles.

Neither is necessarily the ONLY way to look at it. It's all relative.

[–] [email protected] 1 points 10 months ago (1 children)

Semantics. Regenerative braking adds miles of range compared to those without.

[–] [email protected] 2 points 10 months ago

Yes, but it's unrelated to highway versus city performance in electric/hybrid cars.

Driving under highway speeds is almost always more efficient due to wind resistance. But for ICE cars without regenerative brakes the losses from braking and idling hurt enough to give the illusion of freeway efficiency.

And the reason actual highway speed versus the estimates on the sticker are often so far off with ICE cars is that the test is based on 55mph max highway speeds with an average speed of 48mph. Meanwhile the speed limits on all the freeways near me are between 75 and 85, making actual performance way, way worse.

[–] [email protected] 1 points 10 months ago

Important to note though that air resistance is nonlinear


it uses less energy to get from A to B slowly than quickly.