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> EVs can coast too EVs could coast if a manufacturer chose to make one that allowed that without shifting into neutral. In practice, when letting off the acce
by margalabargala 9mo ago
> EVs can coast too
EVs could coast if a manufacturer chose to make one that allowed that without shifting into neutral. In practice, when letting off the accelerator, existing EVs will instead regen brake.
- loosescrews 9mo agoThe default setting just moves the coast point to a slightly depressed accelerator. This is because EVs typically have lower drag, so this behavior mimics a higher drag vehicle. If you use the accelerator to achieve the desired speed, you will coast when possible. You can also monitor the display to see the coast point. My 2013 plug in hybrid only supports this style of operation. Modern EVs have easy adjustment for this. The Hyundai/Kia EVs for example have shift style paddles for adjusting this on the fly which includes a mode for regen only when depressing the break pedal.
- margalabargala 9mo agoThe Hyundai/Kia EVs do not have a mode that only regens when pressing the brake. The best you can do is limit the car to 2kW of regen braking when not touching the accelerator. You can't disable it entirely. It's true though that using this mode will extend the life of your tires.
- Rygian 9mo agoPeople driving an EV learn, in a matter of minutes, to coast by just applying the right amount of pressure on the "gas" pedal.
- margalabargala 9mo agoThey learn to sort of coast. The car feels like it's coasting. Sure. Next time you do this keep an eye on the actual power readout. See if it's actually zero or if it's reporting ~3kW of braking or accelerating.
- Rygian 9mo agoIt hovers depending on how my foot modulates the speed. I don't want or need "exactly zero power readout", I only need to reach my target speed at my target spot on the highway, without having to action the physical brakes at any time. Whether that is more or less efficient than a zero-power coast followed by some kind of braking exactly at the end... I assume the difference is so tiny that it makes no difference.
- margalabargala 9mo agoThe difference is tiny from an energy efficiency perspective. But we're discussing tire wear, and the periodic regen followed by power that a human foot gives because it can't perfectly match the car's PID loop, wears the tires a bit each time. Which adds up over ten thousand miles.
- Rygian 9mo agoIndeed it adds up, over ten thousand kilometers, to a lot less wear than the equivalent coast-then-hit-the-brakes in an ICE. If I follow your reasoning correctly.
- margalabargala 9mo agoLess wear on your brake pads. More on the tires.
- Rygian 9mo agoSo, you say that smoother braking (engine braking) causes more wear on tires than harsher braking (applying brakes)? How so?
- margalabargala 9mo agoWhat? No. We definitely didn't follow one another. I'm confused where we misunderstood one another now. For the purposes of tire wear, applying regen braking in a car is the same as applying brake pads. Generating 5kW of electricity of 10 seconds vs generating 5kW of heat for 10 seconds, same same. Let's say you're on the highway driving in an EV. You have cruise control on. You go down a hill. The EV's cruise control applies regen braking down the hill, using the tires to slow you to your desired speed. Let's say you do the same in an ICE vehicle. You will coast down the hill, gathering speed. Cruise control in an ICE vehicle generally will not brake for you. So more of your energy from the hill gets removed as air resistance. When you slow due to air resistance it does not wear the tires. The same logic applies each time you push the gas pedal slightly harder than you needed to and then back off.
- stahtops 9mo agoPorsche