Introduction to EV Range Estimator Tool for Tires
The EV Range Estimator Tool for Tires is a simple solution designed to help electric vehicle (EV) owners and enthusiasts understand the impact of tire choices on their vehicle’s battery range. Tires play a crucial role in determining an EV’s efficiency and range. One key factor in this is the tire’s rolling resistance – the energy that your car needs to send to your tires to maintain movement at a consistent speed on a flat surface.
Rolling resistance is a measure of how much energy is lost due to the tire’s deformation and the subsequent friction as it rolls over a surface. Lower rolling resistance means less energy is required from the battery to keep the car moving, thereby increasing the vehicle’s range. Conversely, tires with higher rolling resistance consume more power, reducing the overall range.
Our EV Range Estimator Tool focuses on demonstrating how different tire choices, with varying rolling resistance coefficients, can significantly affect the battery range of your EV. By inputting the rolling resistance values of different tires, you can compare and estimate the propulsion power required for each, giving you a clear picture of how your tire selection can influence the efficiency and range of your EV. This tool is essential for making informed decisions about tire purchases, ensuring optimal performance and range for your electric vehicle.
How to Use the EV Range Estimator Tool
- Select Your Car Model: Choose the car model for which you want to calculate the propulsion power from the dropdown list labeled ‘Select Your Car’.
- Determine the Tire Rolling Resistance Coefficients: Refer to the RR tire table below here to find the rolling resistance coefficients (RR) of your tires. These are typically expressed as numerical values.
- Enter the Rolling Resistance Coefficients:
- First Coefficient: In the input field labeled ‘Tire Rolling Resistance Coefficient 1 (N/kN)’, enter the rolling resistance coefficient of your first tire choice.
- Second Coefficient: In the next input field labeled ‘Tire Rolling Resistance Coefficient 2 (N/kN)’, enter the rolling resistance coefficient of another tire choice for comparison.
- Compare the Results: After entering both coefficients, click the ‘Compare’ button. The calculator will display the propulsion power for both tire choices and the percentage difference between them.
- A positive percentage indicates more battery range with the second tire choice.
- A negative percentage indicates less battery range with the second tire choice.
- Interpret the Results: Use the displayed information to understand how different rolling resistance coefficients can affect the propulsion power and, consequently, the battery range of your selected car model.
EV Range Estimator Tool for tires
Geek section: Propulsion Power calculation
Let’s break down the calculation of propulsion power into simpler terms:
- Propulsion Force: This is the total force needed to move your car forward. It includes two main parts: the force to overcome rolling resistance and the force to overcome air resistance (drag).
- Rolling Resistance Force: Think of this as the effort needed to keep your car’s tires rolling on the road. It depends on the car’s weight, the pull of gravity, and the tire’s rolling resistance coefficient – a number that tells you how much resistance the tire gives against the road.
- Air Drag Force: This is like the resistance you feel when you try to move your hand fast through water, but for your car moving through air. It’s calculated using several factors:
- The density of the air (which we’re assuming to be 1.2 kg/m³).
- The car’s drag coefficient (cW), a number that shows how aerodynamic the car is.
- The projected area (A), which is like the shadow of your car cast on the ground if the sun were directly above it.
- The speed of the car, squared. We’re using a constant speed of 60 km/h for this.
- Propulsion Power: This is the amount of power (or energy per time) your car’s engine needs to produce to overcome both rolling resistance and air drag at a given speed. It’s calculated by multiplying the total propulsion force by the speed and then adjusting for the efficiency of the car’s powertrain (which is 70% or 0.7 in our case).
In summary, the propulsion power tells us how much power the car needs to keep moving at a certain speed, considering the tires’ resistance and air drag. The specific values for the car’s weight, drag coefficient, and projected area vary depending on the car model, which is why we use different data for different cars.