Do Electric Bikes Charge When You Pedal?
With the increase of electric mobility devices, cars, and scooters on the road, and rising fuel prices, many of us are looking towards on best electric bikes to get us where we need to go. These faster and more convenient takes on the traditional bicycle combine rechargeable battery power, a motor, and physical pedaling to give you a riding experience which blends footwork with auto-propulsion. They’re smaller than a motorcycle but can go faster than a traditional bike.
So, how does the battery and motor outfit on an electric bike work? And can electric bikes actually recharge themselves as you pedal?
The Batteries and Motor
What make the e-bike unique is the use of lithium ion batteries in conjunction with a motor, to help assist the rider along as he or she pedals. The rider can pedal as they would with a traditional bike, can use the motor to assist them as they pedal, or can use only the motor to power them along; the second and third options rely on a rechargeable battery for power, and during the course of the ride, your battery power will diminish.
Getting the most out of their e-bike batteries, therefore, is a high priority for most riders. For some would-be riders, misunderstandings exist as to just what an e-bike can do, and how it recharges. Let’s clear up one of the biggest myths below.
Regenerative Braking and E-Bikes
One of the most common yet understandable misconceptions is that e-bikes use the kinetic energy generated by normal pedaling to recharge the bike itself as the rider uses his or her feet. While this would be pretty cool, e-bikes don’t actually allow for this yet. What they do allow for is something called “regenerative braking”. You may be familiar with this term being used in the context of cars and SUVs.
Essentially, this technology uses the energy generated when *braking* to recharge the battery. This happens in a car with regenerative braking capabilities, and it can also happen on an e-bike. The reclaimed energy is then transported to the bike’s battery, helping it to regain some of the charge lost through the biking experience. This feature is available on some e-bikes, though it’s rare, and typically found in higher-priced e-bikes. Why is this?
The Motor Behind Regenerative Braking
A key reason why most e-bikes do not have regenerative braking is because of the specific motor type needed the process of energy recycling to work. Most e-bikes have gear-driven motors which are meant to be light weight and relatively simple. They are not designed or internally equipped to re-process the energy generated by braking back to the battery.
A Direct Drive Motor, on the other hand, can handle this, and is the motor type used in e-bikes that utilize regenerative braking. These motors are heavier than gear-driven motors, they can also offer quite a bit of extra resistance if you try to pedal the e-bike once the battery runs out.
Even worse, direct drive motors tend to drain faster, meaning you’ll be more likely to run out of batteries on longer rides, forcing you to drag a more sluggish and heavier bike all the way back home. Having said that, direct drive motors are known for being a bit faster and more durable overall. They’re more complex, and this complexity lends them to being usable for recycling energy back into the battery.
How Much Power Does Regenerative Braking Return to the Bike?
So, if you do decide to go for an electric bike with regenerative braking, how much power can you expect to feed back into the battery through braking? Not a lot. On average, you can expect to recover 5-10% of battery life through braking over the course of your ride. That’s not a whole lot of power, and given the added price tag for the e-bikes that are equipped to recycle this energy, for many manufactures and consumers, the costs outweigh the possible benefits.
The best ways to get extra power when out on an e-bike ride are to
- Store your batteries in a clean, dry, cool environment when not in use
- Balance out your use of pedaling vs. throttle to get the most out of your battery
- Bring along an extra battery pack when you ride
- Post-ride, make sure your batteries have cooled down before you recharge them
- Don’t allow your batteries to drain to zero; keep them at least 20% capacity and then top them up
The Future of E-Bikes
Could we see a pedaling-based regenerative e-bike at any time in the future? This is an undeniably interesting idea, and would certainly allow for longer battery charges on rides and a more efficient machine overall.
Some projects like the Dexquisite’s DX eBike exist which aim to make this dream a reality, and with technological advances racing ahead yearly, it’s certainly possible we’ll see such an e-bike someday.
One such project, the Vello Bike +, claims to be the world’s first self-charging e-bike. That’s a bit of a stretch though. Or, to put it kindly, it’s a bit more complicated than that. The Vello also uses regenerative braking, and recharges itself optimally only when the rider uses it primarily or solely as a traditional bike.
In other words, if you use the Vello’s motor simply to get you moving initially and do nearly all of the pedaling yourself thereafter, the battery can sufficiently recharge itself. Which is great if you plan to get a lot of exercise, but is perhaps not what most of us have in mind when imagining a truly self-charging bike.
As of yet, e-bikes which recharge the batteries through pedaling are not a reality. Options exist to recycle energy generated through braking back into the batteries, but the return on this technology is not very high. Progress is being made, though, and it’s possible that fairly soon, we could see a veritable “perpetual motion” e-bike.
Keep an eye out for indie projects, go-fund-me’s, and new startups over the next couple of years, as one of these companies could make this ideal a reality. Until then, enjoy your e-bike, keep your batteries dry, and ride safe out there.
About the author:
Trevor James is the founder of Electric Bike Paradise, the #1 online retailer of electric bikes, electric scooters, electric skateboards, mobility scooters, electric wheelchairs, electric golf caddies, solar kits, and trolling motors. Trevor has been selling bicycles, electric bikes, and electric scooters online since 2010 and eventually established Electric Bike Paradise in late 2013 when he happened to meet a car enthusiast that introduced him to electric bikes. Trevor spent time searching for electric bikes online but couldn’t find a website that offered a wide selection of electric bikes, scooters, and informational articles. That is why he decided to start a website where everyone can shop conveniently, browse buying guides, and read educational posts. The website is called Electric Bike Paradise.