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Comment by snek_case | Hacker News Reader

It's way more energy efficient if you can learn to drive with regenerative braking. Otherwise you're just wasting energy as heat with your brake pads.

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Coasting is way more efficient than regenerative braking slowing your roll, causing you to need to accelerate again.

Hence why many non-car electrified rides disable Regen braking in Eco mode when your not accelerating or braking as keeping that mechanical energy & momentum is much more efficient than paying the conversion penalty to turn it back into electricity.

As far as I can tell, from the somewhat minimal GUI Tesla gives you, and the general feeling while driving...

You can "coast" with regen on, you just need to balance the accelerator at the point where you aren't adding power, but the car isn't taking power away.

You won't see any green or black on the power usage bar.

Coming down long mountain roads, it's somewhat easier than coasting in an ICE and having to continually shift down gears or ride the brakes (which is obviously bad).

This is correct. You coast by feathering the accelerator.

On my leaf you could feel a very slight change in the pedal resistance at the coast point.

This seems insane to me. "Do nothing and the car coasts" versus "balance this pin and the car coasts" is such a massive dichotomy shift that it seems like poor design. It's a car, not a helicopter.

I've noticed a similar method is needed to coast with a Nissan car with a CVT.

You're massively overestimating the level of effort needed to hold the accelerator steady. The software seems to understand your intent and will help keep the speed relatively steady. Its not like making a millimeter adjustment of the pedal adjusts your speed by 20mph. It took me only a few minutes to get used to it. I'm able to keep a far more even average speed in my electric car than I am my ICE car, as now when I start getting off the gas it actually starts to slow down instead of coasting meaning I'm exerting more control in one motion instead of having to make two motions to achieve the same effect. I'm also usually smoother at slowing down in an electric with heavy regen. I never have to switch between accelerator, not pressing any pedals, to braking. Its just smoothly getting on the accelerator, holding it when I'm at the speed I want, and then slowly getting off the accelerator when I'm wanting to slow or stop. Then once the car stops I take my foot off the pedal and the car holds itself in place.

You're still thinking of pressing the accelerator as "open the throttle on the carburetor this much". On modern cars these days, pressing the accelerator is really more like "I'd like to go this fast", especially in electric cars. Its a vastly different experience.

I don't think I've actually touched my brake pedal in the last 2,000mi in my electric car, and I drive almost exclusively city driving on it.

My exact thoughts but people seem to save energy by turning up the regen? I don’t get it.

If you his the accelerator steady, you can easily keep a pretty constant speed. It's not like you have to either be slamming on the accelerator or completely off the accelerator, you can keep it constant and hold a speed. I really prefer single pedal as with just the single pedal I get far more control of my speed than if I had to switch between two pedals. Want to slow down a little? Just ease up a little. Want to go faster? Just ease a bit more on.

I have not seen coasting modes to be more efficient than single pedal on my own electric car.

Oh my, this reminds me of a Lyft I got home from the airport once. The driver didn't know how to hold the throttle steady and was constantly on and off the gas for the entire 15 mile drive back home on the interstate. I was nauseous and nearly puking by the time I got home, even sitting in the front passenger seat because I'm already prone to motion sickness.

I'm hoping their car was actually broken in some way, because I'm assuming they had owned a license for decades at that point.

However, I'm pessimistic and curious if some people just learn to drive with the constant coasting on and off the throttle? Maybe it's an international thing? I'm not sure but I will never forget that ride!

A certain kind of driver does this. It's as if they live in a binary world. Either "go faster" or "go slower".

Can't be good for their gas mileage (and hence profits!)

Oh god, I feel you. That, but with a 2 y.o. feeling sick in the back, on their way to a pediatrician's office, was my wife's recent experience with one of the faux-taxi services (Bolt or FreeNow, don't remember which), and the driver was lucky - few more minutes of this, and he'd have to do a thorough cleaning of the back of the car.

Regen braking is one of the best features of an EV. I wish I could figure out how to make my Bolt default to 'one pedal' mode. I use the brakes less than 10% of normal now, and it helps me leave more space because I want to maximize the energy return by slowing more slowly.

It depends on the manufacturer, but some cars allow a coasting mode for when the throttle pedal is released and do brake blending for the brake pedal, which prioritises regen and only adds the hydraulic brakes when the regen brake force isn't enough.

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