Roof Box on EVs and How It Affects the Range of Your Tesla
When it comes to maximizing the range of a Tesla or any electric vehicle, aerodynamics and weight play a major role. Three common cargo solutions for EVs are roof racks, roof boxes, and rear boxes. Each of these affects the EV's performance and range differently. Here’s a comparison of how these solutions impact the range of your EV.
Roof Rack for EV
Roof racks are one of the simplest and most affordable solutions for transporting extra cargo. They are often used to attach various types of loads, such as bicycles, skis, or surfboards.
Advantages:
- Easy to install and remove.
- Flexibility to attach different types of cargo.
Disadvantages:
- Increases air resistance even when unloaded, which can negatively affect range.
- Typically not very aerodynamic.
Impact on Range:
A Tesla Model 3 can lose up to 5-10% of its range with an empty roof rack installed. At higher speeds and with a loaded roof rack, the loss can increase depending on the cargo’s shape and size.
Roof Box for EV
Roof boxes are a popular solution for increasing cargo capacity in a safe and weather-protected way. Roof boxes are specially designed to be as aerodynamic as possible.
Advantages:
- Protects cargo from weather and wind.
- Relatively aerodynamic design compared to just a roof rack.
Disadvantages:
- Increases the vehicle’s height and affects aerodynamics.
- Can be cumbersome to load and unload.
Impact on Range:
A roof box affects the vehicle’s aerodynamics more than an empty roof rack, which can reduce range by up to 10-15% depending on size and shape. On long trips, the loss can be even greater.
Rear Box for EV
Rear boxes mount on the vehicle's tow hitch and can be an attractive solution for those who do not want to impact the EV’s aerodynamics as much as with a roof box.
Advantages:
- Less impact on aerodynamics compared to roof boxes and roof racks.
- Easy to load and unload.
- Does not affect vehicle height.
Disadvantages:
- Can affect rear parking sensors and backup camera.
- Requires a tow hitch, which not all cars have.
Impact on Range:
The rear box generally has a smaller negative impact on range compared to a roof box. It can reduce range by approximately 5-10% depending on its design and weight. On highways, the impact is usually less than that of roof boxes.
When considering the best cargo solution to maintain EV range, one should weigh the pros and cons of each option. Generally, roof racks and roof boxes affect range the most due to increased drag, whereas a rear box, though it still causes some loss, has the least impact. For long trips with heavy loads, choosing a rear box can help maximize range.
By understanding how different cargo solutions affect an EV’s aerodynamics and range, you can make more informed decisions for a more efficient and economical journey.
