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Old 05-29-12 | 10:12 PM
  #17  
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Robert C
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Joined: Sep 2006
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From: Kansas

Bikes: This list got too long: several ‘bents, an urban utility e-bike, and a dahon D7 that my daughter has absconded with.

Originally Posted by PatrickGSR94
Do any of these e-bikes have any sort of regeneration circuitry, whereby your time spend pedaling also helps recharge the batteries? Or is pedal power just not enough to make a significant recharge? Or would that add too much pedal effort where otherwise the effort would be acceptable at a given speed, gear, and grade change (i.e. make it feel like you're pedaling uphill when you're on flat or even downhill grade)?

At this point we really are getting into e-bike specific stuff that may be beyond the general topic of commuting; However, I can still answer some of your questions.
Some e-bikes do allow regeneration; however, it does not work well. First, it requires the use of direct drive hub motors instead of, the more efficient, geared hub motors; or, the even more efficient, chain drive motors. Second, it is not linked to the brakes. Most regen in hybrid automobiles comes from using the electric motor as a generator when the brakes are being used. The e-bikes simply do not weigh enough for this to be practical.

As far as pedaling on the flats to regenerate, I would not even consider it. Even if the system were 100% efficient, it would require tremendous input to get any meaningful amount of power stored.

I will add that while I have used an e-bike I have not used one with regenerative capacity. That being said, unless you live on a route with long downhill runs, it has been reported by others to be impractical to plan on using.
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