[dandanthediverman]

I just saw your Hilltopper kits on youtube for the first time yesterday, and I must say, I'm very impressed by the simplicity of the concept - however, I can't help but feel that you're missing a trick here - would it not be possible to build a generator into the hub, so that when the electric motor's not in use the motion of the bicycle is charging the battery? It doesn't need to be anything as complicated as, say the Prius's regenerative braking system, more something along the lines of the old UK Dynohub, which generated a current while offering minimal resistance - alternatively, couldn't the motor itself be switched to a generating mode, when not actually powering the bicycle? While electricity from a battery is clean in use, when it comes to charging it, the power has to be generated somehow, and at the moment that still means fossil fuels to a large extent, whereas a motor/generator option would really put the 'clean' in Clean Republic!

[tincur]

Hello, yes this topic is the frontier I am currently exploring and if there is a question the answer is yes such a system can be employed the technical engineering needed for the controller to switch circuitry has been or claims to be tested and made available ( a dealer is offering a controller with this system but discourages its use because of a "unstable power condition") . Seems to me the switching of mode could be dsiruptive in operation.
So this is my brainchild next assisted power bicycle build project. ?Anyone else interested in this I 'd like to know anything and can offer my specific findings here per request?

[WhiteTiger]

Programmable controllers which can be set for regenerative braking are available on the market, but the gain to be had from regen is so slight with e-bikes as to be not worth the hassle, loss of component warantees and added motor stresses frankly.

You have at most with a heavy bike and rider around 300 lbs of intertial mass, and it's only going to be decelerating from around 20 mph. Even if you arrange switching to engage regen on downhills, the amount of power you can generate is so negligible that the added control complexity plus shortened motor life really isn't worth the effort unless you are just after bragging rights.

With even a light weight sub compact automobile, regen becomes a viable consideration, but there just isn't enough energy to be had with the slight mass of a bike and rider to make things such as voiding all warrantees worth it.

The above is all imo of course, and YMMV.


Tiger

[tobias.runeson]

I would love a solution like that! A motor that helps me out uphill and a generator that charges the battery the rest of the time. Then add a couple of solar tubes and the battery would charge even when the bike's parked.