How to calculate the cost of charging an E-bike battery?

What’s the cost of charging an electric bike? To answer this question and gain a true understanding of the true economics of E-bike ownership into perspective, we’ll need a brief refresher on battery functionality and chemistry. While the initial price of an off-the-shelf E-bike might seem steep compared to a traditional bicycle, the ongoing charging costs are on the modest side. We’ll break down simple calculations that reveal exactly how much it costs to charge an E-bike.

E-bike battery basics

While there are many types of E-bike batteries, most modern models use lithium-ion ones. Generally speaking, these see the widest application across a number of different devices and use cases, like smartphones, laptops, power tools, or even electric vehicles. This is all because of how cost-efficient and safe lithium-ion batteries are (and they’re only getting better!).

Nevertheless, E-bike batteries of this kind typically come with a voltage of either 36V or 48V and a capacity between 10Ah and 20Ah. As you might be aware, commercial electricity is sold in neither of these units; rather, utility companies charge you by the kilowatt-hour (kWh). To understand how much it costs to charge an E-bike, we first need to do some conversions.

Converting battery capacity to kilowatt-hours

Let’s walk through the conversion process. A typical 36V, 10Ah battery has a capacity of 360 watt-hours (calculated by multiplying the voltage by its amp-hours). To convert to kilowatt-hours, we simply divide by 1000 to obtain a larger order of magnitude, giving us 0.36 kWh. Next, we have to calculate power loss in a charger which can transform some energy into heat. Assume 90% efficiency. 

This means each charging your E-bike consumes approximately 0.396 kWh of electricity.

Now, your mileage may vary, of course, depending on the battery specifications mentioned above. A stronger motor on an E-bike designed for avid riders who like to pick up speed will require a more robust battery. If we were to calculate the costs for a 52 V and 20 Ah battery, you’re looking at an expenditure of 1.04 kWh, or almost 3 times as much.

Calculating the cost of charging an E-bike battery

So, let’s get to the answers: how much does it cost to charge an E-bike battery? Using our two examples and the average U.S. residential electricity rate of $0.16 per kilowatt-hour, we arrive at the following conclusions:

• Our first 360Wh battery would cost about 6 cents per full charge ($0.16 × 0.396 kWh).
• Whereas charging our second, larger battery would cost a whopping 18 cents.

Factors affecting E-bike charging costs

As with anything in life, several variables can influence your actual charging expenses.

First, batteries degrade over time. Be it due to standard wear and tear, battery will gradually lose efficiency, internal resistance is growing with charge and discharge cycles. As they do so, they’ll require a little more electricity than their rated capacity to get back up to full charge.

Climate conditions can also significantly impact battery performance. In cold weather, your E-bike’s battery efficiency can drop by up to 30%, potentially requiring more frequent charging during winter months.

Real-World E-bike battery charging costs

When charged to full capacity, an average E-bike will have a range of around 30 miles or 48 kilometers. If you were to charge it every two days for your daily commute and occasional recreational ride, your total costs would amount to around $0.9 a month.

Factor in extra riding time during the weekend, give or take an extra 40 miles/64 kilometers, and you’re looking at an extra 28 cents spent on electricity a month.

You get the point—the cost of charging an E-bike battery amounts to not much more than a pittance. As far as modes of transport go, you can’t ask for a more economical option!

The takeaway

Does an electric bicycle consume a lot of electricity? Not at all! The cost of charging an E-bike battery is really low and won’t run you more than a few dollars a month, even if you use it extensively every day. This efficiency, combined with minimal maintenance requirements, zero fuel costs, and zero carbon emissions, demonstrates why electric bikes represent such a compelling alternative to traditional transportation methods.

You may also read: Which Battery Do I Need for My Electric Bike?