Design a Custom Car

You can now support any car you can think of! However, you have to find out the energy characteristics of your car yourself. This isn't an exact science. I would recommend looking at the parameters for other similar cars and tweaking parameters until you get results that align well with your experience.

If you find something that works well, share it on the forums so others can benefit! Just save your car and send a link to this page and they'll see your current car. You can also search for cars by name to see if someone has designed a model. Just load the car and save it to add it to your account. When you create a car, it will be visible to others likewise.

Happy tripping!

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Parameter Value Description
Name What do you want to name the car, to refer to it later. Don't use the same name as one of the defaults.
Usable Battery What is the usable capacity of this car's battery, in Watt hours
Cubic Parameter EVTripPlanner models the energy usage of a car on flat ground as a cubic polynomial of speed. There is some portion of power consumption which goes up with the cube of speed, some with the square, and so forth. You can think roughly of the cubic parameter as a function of the drag coefficient of the vehicle, and the constant parameter as base power consumption when you're not moving. The best way to pick these parameters is to look at other cars to get a feel for the magnitude, and adjust it to get good results for your car. The units of the cubic parameter are Watts per (meter per second) cubed.
Quadratic Parameter
Linear Parameter
Constant Parameter
Motor Efficiency For every Watt of electricity that goes into the motor, how many Watts of usable work come out?
Regeneration Efficiency For every Watt of physical work that goes into the motor, how many Watts of energy go back to the battery?
Heating Power How many Watts of energy does it take to raise the cabin temperature to 1 degree Fahrenheight above the ambient temperature?
Cooling Power How many Watts of energy does it take to cool the cabin temperature to 1 degree Fahrenheight below the ambient temperature?
Weight How much does the car weight in kilograms?
Temperature Sag The next two parameters describe how severely battery efficiency degrades at low temperatures. Larger parameters mean worse degradation. Unless you're driving at temperatures near freezing, these parameters will have minimal effect. This parameter is a fixed multiplier for the degradation.
Temperature Exponent This parameter describes how rapidly the efficiency degrades as temperature drops. Higher values mean lower efficiency.
Watt Hours per Rated Mile If your car has some kind of "Rated Range" readout, then this parameter is how many true Watt hours in the batter corresponds to one of these artificial units.