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by bluecalm 1251 days ago
The author says his average mileage is 184Wh/km. I've seen similar numbers in other sources: about 200Wh/km.

I am an avid cyclist. When I output 200W for an hour I can go 20-30km depending on the terrain. Maybe 15 if it's steep uphill all the way. Cyclists are not very aerodynamic. They sit high and have boxy shape. A small vehicle can be much more efficient (the reason recumbents beat standard bikes on a track).

It all seems so wasteful to me. It's true sometimes you need to carry load or more people, or go to very steep uphill, or maybe sometimes you really need to go fast. In vast majority of cases though, especially inside populated areas it's one person and a short trip. You carry your 2 ton metal box with you, use 20-30x more energy than a cyclist would and take so much space traffic jams are inevitable.

True innovation those electric cars. The very definition of missing the forest for a tree.

1 comments

Wouldn’t you rather want to compare manually operating a bicycle to an electric bicycle? They’ve basically taken over China for more than a decade now, so it’s not like they are uncommon.
E-bikes are fine. My point was that bikes are not very efficient because of shitty aerodynamics. A light, low and narrow electric vehicle would be more efficient and more palatable to a lot of people than bikes.
Bikes aren’t typically going at speeds where aerodynamics is very relevant. Even E-bikes, maybe e-motorcycles have that problem?
It's not true at all! Most of the forces you have to overcome when cycling are from air resistance. At around 10mph it's already majority of resistance and at about 18mph it's more than 80%.

This is the reason the best upgrade speed wise for a casual road cyclists are tight clothes. This is also the reason you could be way more efficient if you construct a tear drop shaped vehicle. Illustration from Wikipedia: https://en.m.wikipedia.org/wiki/Drag_coefficient