Why does the range of an electric car reduce when you increase the size of the wheels?

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Why does the range of an electric car reduce when you increase the size of the wheels?

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Larger tires are heavier than smaller tires, and when you add more weight to a car, you need to use more force to move that weight. This is what they found when testing this with traditional internal combustion engine cars (good old gas cars) – larger tires similarly made the car use more gas.

https://www.caranddriver.com/features/a15130598/upsized-wheels-tires/

Bigger wheels take more energy to rotate, more than the distance you gain from bigger wheels.

It’s very similar to going fast – going at 120mph takes more than twice as much energy as 60mph, so your range decreases.

This is really strange because on my gas-powered car, I know I get much better mileage on my 19” all season tires than on my 17” winter tires.

With larger diameter wheels, the wheels and tyre combined are heavier. Generally when manufacturers fit larger wheels are both larger in diameter and wider, which means more rolling resistance and (slightly) more air resistance.

It’s a small difference: I drive the world’s loveliest but least practical EV, the Honda e, and the nominal range is 137 miles on 16″ wheels (185/60 at the front, 205/55 at the back) and 131 miles on 17″ wheels (205/45 at the front, 225/45 at the back). 4.4% is in the noise floor: you can get a similar difference by turning the aircon up or down by a degree.

Larger tire means more surface area and heavier tire, also heavier rims. More surface area creates more frictions which requires more power to move the car. Same goes for heavier tires and rims, heavier they are more power required to move. Which ends up using more electric so the range gets reduced.