May 26

A Guide to Understanding Range Variability in Electric Buses

guide to understanding range variability for electric buses

Range Variability 

The number one question asked by most new electric vehicle drivers and operators is: “how far can I go before I run out of charge?” 

While it can be a little confusing to think about the energy in a battery pack instead of the fuel in a tank, the main issue stems from understanding the factors that feed into the changes in range. 

Even though it might be overwhelming at first, in reality, it is not that complicated. 

To help you on your road to electrification, we’ve put together a guide to help boost your understanding of range variability and a few tips for making the most out of the range of your vehicles.

What are the factors that affect the range of an electric vehicle?

Here are a few factors you need to take into consideration:

Weather: Of all factors, the temperature probably has the biggest effect on range. Cold temperatures can slow down charging and cause the battery to drain faster because of heater and defroster use. On the other hand, hot temperatures may trigger additional battery cooling or power limiting measures. While operators can’t control temperature, it can be monitored to catch issues on route before they happen.

Load of the bus: The weight of the passengers or the load the bus is carrying will contribute to how much energy the bus is using on a given route. The more people on board of the bus, the heavier the vehicle will be and thus the smaller the range, 

Traffic: If the bus has to start and stop often due to traffic congestion the battery will be drained more quickly. If the route is smooth the bus will likely use less energy, thus metropolitan routes should expect a lower range than rural or highway routes.

Driver experience: Experienced drivers will be able to anticipate road conditions, as well as brake and accelerate smoothly to conserve energy. A good electric vehicle driver will take advantage of regenerative braking whenever possible. 

Route Conditions: Other factors such as the smoothness of the road or the number of stops along the route also decrease the range.

The Power of  Reports

One way to gain a better understanding of range variability is through data analysis and reporting. Report information will include how far your fleet is able to drive each season, or on particular routes. With data, you are able to make solid predictions for your fleet. 

Without this data, operators are left to guess and compare notes. Quick regular reviews with data or telematics systems will demystify range for your fleet. 

💡Tip: In order to optimize your fleet you can use a platform such as ViriCiti that will create reports full of valuable information. You can then make adjustments based on how often you charge, and to your route accordingly. When doing a check-in analysis keep in mind the weather changes and the different seasons. There will naturally be a change in range affecting the schedule of the bus on the route and when it is necessary to go to the charging station. Over time it is possible to establish a pattern to know what to expect during different seasons and plan the schedule with this in mind.

Driver Training

Driving an electric vehicle is a different experience than driving a diesel vehicle in many ways. As you transition from a diesel to an electric fleet it is important to establish some rules for the drivers regarding charging. For example, many early electric vehicle adopters use a 20% state of charge as a rough guide for drivers to know when they must get to a charger quickly.  It may become clear later on by looking at reports that it is possible to make changes to the initial rule of thumb. For example, the driver being able to continue driving longer than what was originally expected.

This can help manage the use of the chargers, and how often each bus needs to use them. Establishing a system like this is especially critical if you have one charger, like an opportunity charger, that is supposed to support multiple buses on different routes

💡Tip: Offer a brief driver training to your drivers when transitioning from a diesel to an electric bus fleet. Include at what state of charge the buses need to go to the charging station based on your routes. Be sure to practice on route charging with each driver. And for more insights into driving behavior we recommend using a Smart Driving solution such as ViriCiti’s. 

⭐Bonus Resources⭐

Interested to learn more about range variability and how to manage it? Check out this blog answering the following question:

How does cold weather affect electric bus range?

About The Author

We are the ViriCiti marketing team. A group of EV enthusiasts writing about the most important aspects of operating electric fleets. From monitoring to smart charging.