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28-pound electric motor delivers 1000 horsepower (supercarblondie.com)
submitted 10 months ago by to c/technology@lemmy.world
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Maker website: https://yasa.com/news/yasa-smashes-own-unofficial-power-density-world-record-pushing-state-of-the-art-electric-motor-to-staggering-new-59kw-kg-benchmark/

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[–] 21 points 10 months ago (3 children)

I tried to sanity-test the math here running the same calculations on a 700 kg horse, of which around 50% mass is muscle.

700 kg x 50% = 350 kg

Low:

350 kg x 100 W/kg = 35,000 W

35,000 W / 746 ≈ 47 hp

High:

350 kg x 200 W/kg = 70,000 W

70,000 W / 746 ≈ 94 hp

Despite what the term "horsepower" would seem to suggest, a horse can actually output more than one horsepower. Estimates put peak output of a horse around 12-15 hp. By those numbers, even the low end estimate above is around 3-4x too high. We're gonna need more dogs.

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  • [–] 7 points 10 months ago (1 child)

    I appreciate the sanity check, but just to throw a monkey wrench into your model...

    I think the square-cube law will bite you here. I expect power/mass isn't constant. Mass grows faster than cross-sectional area which is key in muscle performance.

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  • [–] 4 points 10 months ago

    Horsepower was originally used to describe the work that a horse could do over the course of an hour. Specifically, the number of times an hour a horse could turn a mill wheel at a brewery. These are estimates of peak power, not sustained power, so I would say that it's accurate that horses can produce significantly more than one horsepower in short bursts.

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