From a commenter under the video:
Summarized the measurements, with rough timestamps:
Stock blades (6:43): 1 m/s, 64.3 W,
simple airfoil (7:55): 0.8 m/s, 66 W
modern airfoil (9:12): 1.2 m/s, 64.5 W
stock motor no blades (13:49): 53.8 W
BLDC motor no blades (16:24): 8 W
BLDC stock blades (18:27): 1.8 m/s, 59 W
BLDC stock blades at reduced speed (19:35): 1.0 m/s, 27.3 W
Interesting video, thanks for tabulating the data
I’m surprised he is measuring with the fan so close to the ground, with the electronics obstructing the fan downwash, with the anemometer so close to the fan, with the anemometer so close to the edge of the fan, and with the anemometer so irrepeatably placed…
I don’t think he has accurately measured the efficiency of the induction motor (no load -> stock blades @ 1 m/s is a power change of 10.5 induction and 19.3 for bldc). He is pretty casual in his dismissal of the cost premium of bldc motors too.