Self charging technology

[nickw1965]

With the new hybrid cars incorporating self charging technology.Why hasn’t a element of this been used on e bike design.It must be logical that nearly 50% of a ride has downhill elements that to a point require no pedalling.In my youth we had dynamos for front and rear lights.I’m not saying you can get a huge percentage of charge back but is 25% not realistic over a days ride.

 

[Gary]

No

 

[nickw1965]

Gary The word “no” isn’t in my vocabulary.Just means it hasn’t been invented yet

 

[nickw1965]

It appears the concept has already been invented.Now only a matter of time

 

[All Mountain Coaching]

I've said why don't they have like a kers system to recharge. If they can improve on the fast chargers and maybe get 80% down to half hour there'll be no point.

I'd love to start seeing charging points at trail centres.

 

[MattyB]

With the new hybrid cars incorporating self charging technology.Why hasn’t a element of this been used on e bike design.It must be logical that nearly 50% of a ride has downhill elements that to a point require no pedalling.In my youth we had dynamos for front and rear lights.I’m not saying you can get a huge percentage of charge back but is 25% not realistic over a days ride.

No, not really for a number of reasons...

• The amount of kinetic energy in a bike isn’t that big due to the low overall weight of the system (bike+rider) compared to a car or truck, so recovering it would markedly slow the bike beyond what we normally need when descending.
• The system itself would add more weight to the bike, weight that has to be propelled along by the rider and motor. Energy expended doing that would be greater than energy recovered by the system on descents.
• On the flat or uphill running the motor and riders effort against the additional load of a generator to recover charge makes no sense. This is due to the inherent inefficiencies of such a setup and the fact it adds additional load to the rider which they are unlikely to be able or Willi no to make. A simpler and more efficient solution in that situation is just to reduce the assistance level slightly to gain more range.

 

[Gary]

I've said why don't they have like a kers system to recharge

Because mountainbikes don't have engine braking a flywheel would have to be incorporated along with some form of alternator/charger. The added weight/drag of such a device would not be worth the tiny amount of charge created.

Just switch your motor off if you want to save battery.

 

[GuyBerry]

It appears the concept has already been invented.Now only a matter of time

View attachment 9232

This is not self charging, but charged by pedaling, good luck .

 

[OldBean]

The old style dynamos created a huge amount of drag ..I hated them on my school to home ride !
Better batteries will come just wait a bit.

 

[Brianjonesphoto]

I’ve thought regen braking should be part of ebikes especially emtb. The motors already have a front flywheel. It would be nice to have a ebike specific free hub that worked more like fixed hub with a clutch for safety. Then the chain is always in motion and you could shift anytime the bike is in motion. Half of the shift under load issues solved right there. Chain slap would also be less of an issue.

You also do not need any other weighty components to implement regen braking once the chain in in constant motion. An electric motor driven my the output shaft will produce electric current. All DC electric motors are generators when run backwards there are usually diode in the motor to prevent this from happening. Maybe a circuit board to manage that element as well as a micro switch and wires to each brake lever. Imagine pulling the rear brake and the first 30% of the pull is charging your battery they when you want to lock up your wheel the caliper takes over.

It wouldn’t be big numbers but might net you 5-15% in range. Maybe enough for one more run.

It could be done and I bet it will happen in the next generation or 2 of ebikes. Not that difficult to implement.

 

[Pivot]

We need the (original) Tesla power supply over the air!
E.g. https://newatlas.com/energy/long-range-wireless-power-transmission-new-zealand-emrod/

 

[Swissrider]

I've said why don't they have like a kers system to recharge. If they can improve on the fast chargers and maybe get 80% down to half hour there'll be no point.

I'd love to start seeing charging points at trail centres.

There already here in Switzerlan, even saw one at the Chanrion cabane at 2200m in the Val de Bagnes, Valais.

 

[RustyIron]

On the car, regeneration takes your forward momentum and converts it to electrical energy. For most of our styles of riding, we don't want anything sapping our forward momentum and our speed. Regen might be beneficial to the rider who does a lot of long downhill fireroads while dragging the brakes, but for everyone else, it would be awful.