Truth: How far can an e-bike really go on a single charge?

One of the biggest benefits of e-bikes is that they can help riders go further with the same leg power. But with manufacturers quoting wildly different range ratings for seemingly similar e-bikes, how can you tell what an e-bike’s true range is?

It’s actually easier than you think. And after spending over a decade working in the e-bike industry, I’ve gotten pretty good at it, if I may say so myself. Here are my tips for getting a true and honest assessment of an e-bike’s range.

What are the autonomy factors of the electric bike?

First things first: One of the reasons e-bike range ratings seem to be all over the place is because they can be affected by a number of factors.

Everything from speed and rider weight to terrain style, wind conditions and even tire choice can impact an e-bike’s effective range on a single charge.

The second major factor is the presence (or absence) of a hand throttle. Most European cyclists won’t have to take this into account as e-bike shifters are not common in EU countries. But for Americans and riders in other countries that allow hand throttles in addition to pedal assist, a hand throttle can be a quick way to drain the battery and reduce range.

A throttle can be handy, but it will drain the battery faster than pedal assist

How to estimate the range of an electric bike

To determine the approximate range of an electric bike, you must first start with the capacity of the battery. It is usually measured in Watt-hours (Wh). Sometimes you will see a battery rated in volts and amp-hours, such as an e-bike with a 48V 10Ah battery. To convert to Wh, simply multiply volts by amp-hours. A 48V and 10Ah battery is therefore a 480 Wh battery.

Then you can calculate the effective range by simply dividing the battery’s watt-hour capacity by an average efficiency number in Wh/mi (or Wh/km if you prefer miles).

This is the slightly fuzzy part of the calculations, as efficiency numbers vary based on the factors listed at the beginning of this article. But speaking in general, I find that most 500-750W throttle e-bikes running at an average speed of 20 mph (32 km/h) on slightly hilly terrain get me about 25 Wh/mi (or 15.6 Wh/km ). So an e-bike of this style with a 480 Wh battery would give me about 19 miles of range (480 Wh ÷ 25 Wh/mi = 19.2 miles).

Pedaling assistance will always be more efficient. I find that most pedal-assist e-bikes going around 15-18 mph with medium levels of pedal assist will get me around 15 Wh/mi (or 9.4 Wh/km). So the same 480 Wh battery on a pedal-assist e-bike will give me about 32 miles of range (480 Wh ÷ 15 Wh/mi = 32 miles).

You can use the same calculations for different battery sizes to calculate an estimated range under real conditions. However, you may want to make adjustments to the numbers to better suit your needs, as I explain next.

You can adjust these numbers based on your specific scenario

For reference, I weigh about 155 lbs (70 kg). If you’re a bigger guy, you might want to use a figure closer to 30 Wh/mi on throttle bikes, for example. Or if you’re a little slippery, you might get closer to 20 Wh/mi. My wife always has better range than me, and the fact that she weighs 45 lbs (20 kg) less than me is a big part of that. More weight means the bike has to use more energy, especially when accelerating and climbing.

You can also change these numbers depending on the terrain. I usually ride on slightly hilly terrain. If you’re rolling on a pancake, you can use slightly better efficiency numbers. If you’re climbing bigger hills, you’ll want to use slightly lower efficiency numbers.

But for starters, 25 Wh/mi on throttle e-bikes and 15 Wh/mi on pedal-assist e-bikes is a good starting point for a reasonable range estimate.

yamaha wabash electric bike

What if I’m a really strong pedaler?

I’ve got you covered too, you strong pedallers!

I usually ride with a mid-level pedal assist mode selected, which is why I get around 15 Wh/mi on most pedal assist e-bikes. That’s a solid number for me when commuting or running errands. At those times, I definitely use my legs to add support, but I don’t go crazy with fitness.

However, when I really want to exercise, I stick to level 1 pedal assist and the efficiency can often skyrocket. I recently documented a 29 mile (47 km) e-bike ride I took where I used only 90 Wh of power staying in level 1 pedal assist as much as possible. ran at an insane 3.1Wh/mi!

I was pretty much dead after that ride so I wouldn’t recommend riding at this level every day unless you’re a super fit rider (I’m not) but it was a great experience to see what can happen when you push yourself and your bike to the limit.

swytch kit trail ride

What about extreme range ratings on e-bikes? Are they true?

We can use these equations to test a few examples of ultra-high-end e-bikes to see if the manufacturers are realistic.

The Specialized Turbo Vado SL e-bike was recently launched and comes with a range of 80 miles from its 320Wh internal battery or 120 miles with an additional 160Wh booster battery.

At my normal efficiency of 15 Wh/mi with medium pedal assist, this bike would probably take me around 21 miles with its built-in battery or 32 miles with its booster battery. However, realistically the narrower tires, lower weight and higher efficiency of this bike will probably translate to a little better range than this as I will be riding more efficiently than most of my e-bikes with pedal assist. cheaper pedaling.

But if I drop it in the lowest pedal assist mode and get closer to my 3.1 Wh/mi efficiency when pedaling really hard on this bike, that would equate to a range of a bit over 100 miles on the internal battery!

Obviously, it’s over a sweat-soaked, multi-hour fitness session, but you get the idea. By adding more of your own pedal power and using lower pedal assist modes, the range of an e-bike can be significantly increased, which is where manufacturers often get those high numbers.

Ultimately, most people will never achieve yields below 5 Wh/mi unless they push really hard and train hard. For everyday driving, 25 Wh/mi on throttle-only driving and 15 Wh/mi on modest pedal-assist driving are both good numbers for real-world range estimates.

Did you do your own range tests? I’d love to hear about your experiences – let me know in the comments section below!

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