UK-based YASA has just built a tiny electric motor that makes Tesla motors look like slackers, and this invention could potentially reshape the future of EVs
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.
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.
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.
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.
I accept your terms.
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.
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.
Fair
Might be my favorite thread today. Thank you, polite and nerdy strangers.