What do watt ratings for an e-bike actually mean?

What do watt ratings for an e-bike actually mean?

To gain some insight into what power means, consider how many watts a typical biker consumes when cycling at a normal speed. At a steady pace or around 10 mph a rider is required to to expel around 30 watts. When a rider elevates their speed up to 20 mph or comes across an incline riders needs can easily expand past 200 watts. Riding up a grade of just 8-10 percent grade can take 150 watts. Both of those are enough to have most riders breathing and sweating heavily.

E-bike Energy

Another essential element of eBikes is energy. Acceleration is concerned with power, but range is concerned with energy. In a motorcycle for instance, energy is stored as gasoline and converted into power. As a result, in a car, we don’t usually think about energy; instead, we consider how many gallons of gas we have.

We can look at e-bikes in similar terms to the amount of gas in a car. The battery stores energy and distributes it to the bike’s electric motor to produce power. The watt-hour is a unit of electric potential that tells how much electrical energy may be produced for an hour by a battery. Typical eBike batteries have a capacity ranging from 300 to 1,000 Wh (abbreviated WH).

Mileage varies from eBike to eBike, just like automobiles. The US Environmental Protection Agency (EPA) has a system for rating electric cars and comparing them to gasoline vehicles, this is called MPGe (miles-per-gallon-electric). An electric vehicle has an EPA score of around 100 MPGe.


A more essential number is the watt-hours consumed per mile of travel, if you want to be able to figure out your range. The number is usually between 10 and 20 watts per mile depending on the bike, your travel speed, and how strong the electric assist is engaged. This simple look reveals that a 300-WH battery may get you 15 to 30 miles. If you’re a cyclist seeking for longer bike rides at a high-boost level, you’ll probably want a bigger battery.

Most eBikes come with a basic bar and/or percentage dials indicating the condition of their battery charge. You’ll quickly learn your battery’s power and develop an intuitive feeling for how far you can go without using any math. And, unlike an electric vehicle, if you run out of power, you can just pedal home without any damage done to the motor or battery.


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