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There are several different electric bicycles with different power outputs. From adorable 250 Watt e-bikes to e-bikes with enormously excessive 10+ kW motorbike-level power. But how much power do you need personally?
The answer will largely rely on your weight and whether you want to ride up plenty of huge hills. You require more power to accelerate the ebike the heavier you are. You will require more power to ascend a slope that is longer and steeper than it is short.
A pair of 500 W motors from various E-bike manufacturers may have somewhat varying power levels due to the multiple standards used to measure electric motor power ratings. E-bikes come in a wide variety of styles and power levels, so choosing the correct power for you is a very individual choice.
However, remember that just because two motors share the same label doesn't mean they're the same.
At speeds up to 20 miles per hour (mph), the power output needed by a cyclist is similar to that needed for walking. Above that speed, however, the power requirements increase dramatically. For example, at 22 mph, the power requirement increases from 300 watts to 1,000 watts.
150 watts are required to ride up a gentle 10 percent incline at a speed that is just faster than walking; this is enough to make most riders breathe and perspire profusely.
To get some perspective on what power does in human terms, let's take a glance at how much wattage a typical cyclist would require to ride at a typical cruising speed. At a slow pace, around 9mph, only 30watt is needed.
But if you go up to 20mph, your body starts working harder, so you'll need to burn around 220watt. And if you're riding uphill, you'll need to work even harder, burning up to 300watt.
So, to give you an idea of what kind of effort it requires to ride at high speeds, think of it like this: A typical non-athlete could easily do a little exercise every day and not feel any difference. However, if you were to start training for a triathlon, you'd probably notice a big change after a couple of weeks.
You might find yourself feeling tired during the day, and having trouble sleeping at night. That's because you've started exercising at a higher intensity level, and your body needs to adjust to that new workload.
Another important aspect of electric bicycles is energy. Energy is about speed, not distance. A conventional bicycle stores energy in the form of fuel (usually liquid petroleum) and converts it into mechanical work through the cyclist's legs.
Accordingly, in a bicycle, we don't explicitly consider energy, only the amount of fuel we have and how fast that's likely to get us.
Electric bicycles are much more direct. They store electricity in the battery cells and feed it into an electric drive system. The amount of power produced depends on the size of the electric bike battery(Mostly lithium batteries).
Small battery life might produce only enough E-bike power to move the bicycle forward for a short distance. A larger Ebike battery could provide enough actual power output to propel the bicycle for longer distances.
As with cars, bike mileage varies. The US Environmental Protection Agency (EPA) originated a system to rate electric cars and to compare them against gasoline cars, something it called MPGe (miles-per-gallon-electric).
An electric car typically gets 90 to 130 MPGe. Most e-bikes get somewhere around 2,000 MPGe on this measure, roughly 20 times more efficient.
However, if you want to be able to calculate your range accurately, a more important number than watts is the number of WH (watts multiplied by time) consumed per mile of travel. It is usually between 10 and 20 WH per mile.
That means that a typical 300-WH ideal battery could take you anywhere from 15 to 30 minutes on an electric bicycle (bicycle). If you want to go longer distances on weekends at continuous power, you may need a larger battery.
A 250-watt (W) electric bike has a lower power output than most other classes.
You're talking about a flat road cruiser with 250 watts of electrical power. Most 200-watt (W) e-bikes are small scooters, but some come equipped with 250-watt ebike motors.
At this level of power, most 250-watt e-bikes won't be able to go up steep inclines without help from the rider. However, mid-drive motors tend to outperform hub-driven bikes at this power level because they can generate more torque when shifting their gears.
Motor controllers are used to controlling motors.
Even if the ground is flat, an average person who is on the heavier side can still ride a 250W electric bicycle. It will carry them even though the acceleration is quite slow.
It's important to remember that the lighter riders produce less power when pedaling than 250 watts continuously.
For instance, if you weigh 70 kg, a 250 W bike may be comfortable for you. But as soon as you start climbing hills, the performance swiftly drops off and the bike starts to sluggishly move.
Heavyweight cyclists shouldn't try to ride up steep hills without risking their motors overheating. However, riding up steep hills will still significantly decrease the power output of a heavy cyclist's 250-watt ebikes.
Heavier riders may occasionally still find 250 W mid-drives acceptable for little slopes, especially if they desire to add some pedal input. A 250 W capacity batteries just does not have enough power or torque to propel heavier riders over medium-sized slopes at a respectable rate of speed.
A typical 250-watt motor can travel up to 20 miles per hour. Above this speed, additional power needs to be applied to the motor to counteract the effects of air drag.
Acceleration increases with the next increase in power. E-bikes with 250 W motors are slow to accelerate, but those with motors closer to 500 W will accelerate considerably more quickly.
This will seem like a huge difference to lighters riders. However, depending on the motor, heavier riders might not notice a significant difference when traveling over flat ground. 500 W will be much more effective in propelling light riders to the top of slopes. For heavier riders, smaller hills could become more manageable. However, these riders won't notice a significant improvement over 250 W engines with lower power on any respectable climb.
It should be noted that an e-bike typically needs 500 Watts of power of electricity or more to travel faster than 32 km/h (20 mph).
Once you achieve 750 watts, you'll be able to get substantially more exciting acceleration off the mark than when you were riding at 500 watts. Furthermore, at this level, your hill climbing ability will begin to improve.
For heavier cyclists, when flat-land performance reaches 750 watts of power, climbing uphill becomes consistently possible. But most heavy cyclists will be happier with the 1,000-watt performance.
With 750 W e‑bicycles, speeds of up to 28 miles per hour (45 kilometers per hour) are becoming more common. You may still find 250 W e‑bicycles with a “750 W” motor and a maximum speed of 28 miles per hour (or 45 kilometers per hour).
Moreover, we have written an article about how fast a 1000W ebike can go. It will help if you read it.
