Title text:
"How does the spring not run out almost immediately?" "We pull it back REALLY far."
Transcript:
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Source: https://xkcd.com/3244/
this post was submitted on 12 May 2026
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I can't remember which car but an early hybrid vehicle did charge up a flywheel instead of an electric battery…
I heard about a version that used springs as well. Basically a pull-back car: When you break, it puts tension on the springs, then it releases that tension when accelerating. Apparently it was very good for city-driving, since you get an absurd number of cycles with very small "charges", which makes it very good when you do a lot of start/stop driving in slow traffic. I'm not sure why I haven't heard any more about it in more recent years.
*brake*
Idk about you, but I usually build tension when I break.
I build tension before I break, but maybe I'm weird.
That's right the actual moment of breaking usually releases tension, but the overall process of breaking includes building it up!