[pahool]

> The Author is arguing for replacing the chain with power wires, by generating power from pedaling and feeding it into the motor (with efficiency losses of 5%)

My understanding is that the efficiency loss is strictly limited to delivering electrical power back to mechanical power via motor instead of via the chain drive. The problem with this design is that it completely eliminates the ability to deliver mechanical energy directly. The rider pedaling charges the battery which then powers the motor. Going from mechanical energy to stored electrical energy is going to introduce a much greater loss in efficiency than a mere 5%. In a more standard e-bike model, when the rider pedals, my understanding is that they are delivering mechanical energy directly, bypassing the conversion to electrical energy. I may be wrong as I am not very familiar with e-bikes, but, if this is the case, the 5% figure seems highly misleading.

[danhor]

There's no need to go via the battery. The electrical energy from the generator is directly used by the motor, only the excess energy (if there is any) gets stored in the battery. Both generators and motors can be very efficient (and of course the conventional chain also has some losses).

See https://electrek.co/2021/08/31/radical-new-electric-bike-dri...

Real, especially cost reduced, systems could be a lot worse thougn.