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by _nhynes 2546 days ago
human: 1.2 (0.9) kcal/floor ascending (descending) [0, 1] elevator: 2.5 W•h/floor [2, 3]

Let's assume 15 floors since otherwise you'd probably save time walking.

The article suggests a grid efficiency of 50% and a motor efficiency of electric e-bike motors as 75%. It looks like elevator motors are actually more efficient (increasingly so as more people are loaded) [4]. It's only about 5 percentage points higher, so for simplicity let's keep 75%.

Ignoring the transportation and manufacture cost of the elevator assembly (not totally unreasonable since it has a long lifetime), elevators have an energy ratio of 2.5:6.7 or 1:2.7, which looks far better than the 1:28 that the article quotes for humans.

Gee, that kind of upends my worldview... I guess I'll just wait until bodies are deprecated in favor of high-efficiency cybernetics.

[0] https://captaincalculator.com/health/calorie/calories-burned...

[1] https://www.livestrong.com/article/301539-calories-burned-cl...

[2] https://www.quora.com/How-much-electricity-does-an-elevator-...

[3] https://fatknowledge.blogspot.com/2007/02/how-much-energy-do...

[4] https://www.me.ua.edu/me416/LECTURE%20MATERIALS/MotorEffic&P...

1 comments

> Let's assume 15 floors since otherwise you'd probably save time walking.

Not many people would consider walking 15 floors either up or downstairs. Actually many people pant heavily when climbing (from their point of view) 3 floors to my place.