“Flywheel can replace electric bicycle motor”

A flywheel is in fact a mechanical battery. Could you also use this on an electric bike?

What is a Flywheel?

We use the wheels that we use in daily life to move ourselves, or for example a mechanism such as a clock.

A flywheel does something completely different, which is to store energy. The faster the flywheel turns, the more energy it has stored. You can also tap this energy. The great thing about flywheels is that you can put energy in or out very quickly. Also, almost no energy is lost when charging and draining flywheels.

But there are also disadvantages. For example, flywheels cannot store energy well for a long time because of the friction. You can also not store as much energy per kilo as in chemical batteries, such as the lithium ion battery in electric bicycles.

Why a flywheel on a bicycle is quite useful. In theory

Especially in city traffic you often have to brake and then start up again when you’re on the bike. For example for traffic lights. This energy is lost as heat. But what if you could store this energy in a flywheel? Then you can leave again with flying speed.

That’s exactly what happens with the Flywheel Bicycle of Maxwell von Stein, a student at New York City’s Cooper Union for the Advancement of Science and Art. When you brake on this bike, the built-in flywheel is “charged” with your kinetic energy. Does the traffic light turn green again? Then you drain the flywheel, and you blast away at full speed. All this purely on your muscle power, without the need for a motor.

“In this form it makes almost no difference”

Maxwell von Stein used a 6.8 kg flywheel from a car for his contraption. This nearly doubled the bike’s weight, making it take more energy to propel.

Calculations show that the energy saved by the flywheel roughly outweighs the extra energy you need to propel the heavy bicycle.

But you have to bear in mind that Maxwell’s invention has not yet been improved. For example, you can think of a lighter flywheel that rotates much faster and still stores the same amount of energy. And a more efficient system than the bicycle chain used by the student. You should also place the flywheel lower, the ideal place would be a dual flywheel around the rear wheel.

So you see that you can also come to an end with low-tech solutions, although of course this does not match the comfort and convenience of an electric bicycle, for example a Sparta or a Gazelle.