When do you think we will get Downhill battery charge regeneration?

[Ron]

I’m hope some clever engineer is working on a EMTB system to recharge the battery using a little of the kenetic energy when going downhill or braking, like a hybrid auto does. This would allow a smaller battery and longer range? I’m sure there are technical issues to overcome, the least of which is added weight, but seems possible to me?

 

[Mabman]

It's already available but you need a direct drive hub in order to get regen. I have it on my front hub road bikes and it works great as a braking supplement primarily. It does add a little back to the battery but will never add as much as it will in a car system due to vehicle weight being a major factor.

You will never get regen out of any geared type motor system unless you put a dynamo hub in the mix.

 

[MattyB]

Probably never. Pushing along the additional weight of kit needed to recover the energy would far exceed the energy it produced at this point. Increasing the energy density of batteries (even though that in itself is still difficult) is a far more likely and efficient way of increasing the available electrical energy.

 

[Simon_t]

I think the biggest reason why it won’t be useful on MTBs is that there would be too much braking effect if you were to get any useful regen out of it. I don’t want to be slowed down on most hills. It would only be useful in the steepest of downhills, and how much of most of rides is like that?

Simon

 

[Tamas]

Personally, I wouldn’t want regen braking on downhills I want to go fast... Also, considering the added weight/complication/price/questionable efficiency I think a 20% bigger battery is a much better solution.

 

[Ron]

Great input guys!

 

[dirt huffer]

At best with a good sinewave controller and higher efficiency hub motor, you can expect about a 5% return on battery power. It's not a lot but it saves your brake pads. Regen braking can be very useful if you only need to use 1 brake (usually the back brake on a hub motor) You can use both brakes, but then you're limiting the amount of regen possible. Regen braking is way more useful road biking and commuting in my opinion but i think it's something we'll see more of in the future as the technology progresses

 

[All Mountain Coaching]

Having run out of juice on a recent ride I started to question why, or how long, it'll take until we get a kers/recharge system. I biked several miles with it off, surely that'd give me something back?!

That's the exciting thing about ebikes, there's plenty of tech to evolve.

 

[R120]

Would be good if there was a way of recharging by pedalling with motor off/no assistance or some such

 

[gregjet]

Rather than a regen at the motor and the loss of the double freewheel, or a big heavy hub motor, you could attach the gen drive to the front and rear disc brake arms and have the coild attached to the frame. Easier to make it lighter. Carbon fibre wiring or graphene doped Al or Cu to reduce weight. Graphene is gonna get cheaper relatively soon. Gen or alternator frame can be crabon fibre composite. Make it manually switchable so it can be used as a descending "brake" to help control difficult downhill and add a bit more distance, or switched out when you need the speed downhill.

 

[Shane]

I doubt we’ll see it. The money for the R&D just simply isn’t there. There the cash is being spent is on making batteries higher capacity and lower weight. Essentially batteries will just keep improving until the point where regen is a non-issue.

 

[gregjet]

I doubt we’ll see it. The money for the R&D just simply isn’t there. There the cash is being spent is on making batteries higher capacity and lower weight. Essentially batteries will just keep improving until the point where regen is a non-issue.

That certainly is the prime concern at the moment ( that, and for me weight)

 

[All Mountain Coaching]

The race is on. Exciting times regardless.

I doubt we’ll see it. The money for the R&D just simply isn’t there. There the cash is being spent is on making batteries higher capacity and lower weight. Essentially batteries will just keep improving until the point where regen is a non-issue.