Will a roof rack on the Model Y cause a big range reduction?
If you add a roof rack to your Tesla Model Y, its efficiency is going to take a hit. However, the good news is, it's very minor. This is especially true if you stick with the product that Tesla offers, which costs $450. There are likely non-Tesla products that work just as well and cost less, but this particular test only focuses on the Tesla roof rack. According to the automaker:
"The Model Y Roof Rack was designed and engineered from the ground up for maximum aerodynamic efficiency, minimal interior noise and impact to range."
It's no surprise that items like roof racks, bicycle racks, cargo toppers, and tailgate shelves will cause your vehicle to be less efficient. They add weight and disrupt the car's aerodynamics. You'll likely hear the extra drag in the form of wind noise, and if you check your vehicle's efficiency with and without the item installed, you'll be able to record the difference.
While these aftermarket items can reduce efficiency and range, many drivers of gas-powered cars probably pay little attention to the drop. However, most EVs owners are all about range and efficiency, so it makes sense that they'd check the numbers.
Brian Jenkins (i1Tesla) drives 60 miles with and without the Tesla roof rack to get an idea of its impact on his Model Y's efficiency. He's happy to report that the car consumes 281 Wh/mile with the roof rack installed versus 278 without. So, the difference is almost unnoticeable at about 1 percent. He's not so happy with the amount of wind noise, however, though he says you won't notice it much with music on.
Video Description via i1Tesla on YouTube:
Model Y Roof Rack Efficiency Effect
Drove 60 miles to test out the effect that the roof rack has on the Tesla Model Y.