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Isn't this just transferring energy from the car towing to the Tesla itself? My understanding is this production of power induces some friction, that otherwise would've been closer to neutral.

In other words, if the wheels were completely free to spin, would not the towing car require less power to tow?

Or is my understanding of this off? Physics was a long time ago

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Yes, there's no claim of free energy or perpetual motion here. The author even discusses approximately how efficient the charging is in the video.

Oh yeah I guess I worded it wrong; I wasn't imagining free energy.

Framing it as an efficiency question is more clear, thanks. In other words, this way of converting $natural_resource to Tesla battery level is less efficient than say, plugging into a power grid as there's an extra conversion step (ground to brakes/ambient friction).

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