[BoltEUV]

I'm using my one pedal driving to save on the brakes and also to avoid pushing on the brake pedal at a stop light.
So, what's the most energy efficient way to come to a stop? Coast or regen?

Providing you have room to coast and don't have anyone riding your tailgate of course.

 

[wesley]

Bolt can’t really “coast” in D because it’s simulating the feel of an ICEV by doing a bit of regen. So if you’re referring to coasting by taking the foot off the acceleration pedal in D, question becomes essentially like asking whether a low amount of regen is more efficient than a high amount or not. In that case I found the difference to be minimal.

if you’re really coasting, as in keeping the energy expenditure at really close to 0kW on the dashboard no matter what, then it should be technically more efficient than using regen. But that would take a really long time to come to a stop and thus not be practical.

So you should just use any form of regen to come to a stop and avoid using physical brakes in order to be efficient.

 

[Jrvaughn]

I'm using my one pedal driving to save on the brakes and also to avoid pushing on the brake pedal at a stop light.
So, what's the most energy efficient way to come to a stop? Coast or regen?

Providing you have room to coast and don't have anyone riding your tailgate of course.

I found that "coasting" to be more difficult estimating stopping distance.

 

[The Other Tom]

It's more energy efficient to regen to a stop because you're adding energy back into the battery. Coasting, if you can do it, doesn't add energy back.

 

[ARob]

This topic always seems to generate passionate opinions both ways. My experience (88K miles) suggests it makes so little difference if you drive relatively efficiently that it probably isn't worth getting worked up about it. I mean, a .1 mi/kWh difference is so insignificant that one has to ask, why bother sweating over it?

Hypermiling requires patience and skill well beyond what most drivers can accomplish consistently. Add unpredictability of conditions (climate or other drivers) and it is even more daunting to get a good comparison.

 

[Collin80]

Coasting will always be more efficient because you're using all the energy you can use. The only waste is air resistance and rolling resistance and you can't help those. Well, you can lower air resistance by lowing the speed but at a given speed you'll get a given resistance. If you can coast all the way to a stop you have used all the energy you can use. But, you won't enjoy this. We tend to want to travel at a given speed then slow down more quickly when it is time to stop. You can either regen to slow down or use the friction brakes. Obviously then regen wins as you are putting some energy back. But, the original example is a stop light. If you see the light turn red in front of you then you need to stop. You probably don't have room to coast to a stop. The car will coast for something like a mile if you put it in neutral at 60mph and just coast it. You probably aren't going to time the light right at that point. The best general answer is to coast as much as you can for as long as you can and use regen to slow down the rest of the way as much as possible. That's basically the best you can do.

 

[Martin D]

This topic always seems to generate passionate opinions both ways. My experience (88K miles) suggests it makes so little difference if you drive relatively efficiently that it probably isn't worth getting worked up about it. I mean, a .1 mi/kWh difference is so insignificant that one has to ask, why bother sweating over it?

Hypermiling requires patience and skill well beyond what most drivers can accomplish consistently. Add unpredictability of conditions (climate or other drivers) and it is even more daunting to get a good comparison.

It’s nice to see people passionate about their driving. But I completely agree with you that it’s not going to make much difference. I like using regen or L as an aid to driving, and it is definitely going to save on brake pad replacement. I would suspect that the brakes will never wear-out if regen is always used.

I notice that the regen recouped is about 25% less than the energy expelled by acceleration. So I don’t think that coasting is going to offset the acceleration, but it would lower the energy used for the coasting phase. Which is actually more efficient than the other is only going to answered by a scientific study, but it would be a monumental effort of concentration to try to stay within a coasting discipline while it might be more prudent to be concentrating on the traffic and what is going on around you. YMMV

 

[Jim99]

I’ve tried both the regen mode and coasting in the D mode and I have found no difference in the efficiency between the two.

like the regen mode better than coasting in D, and that’s become my preferred setting. It now only goes into the D mode if my wife is driving the Bolt. She does not like the regen mode at all.

 

[GJETSON]

I'm using my one pedal driving to save on the brakes and also to avoid pushing on the brake pedal at a stop light.
So, what's the most energy efficient way to come to a stop? Coast or regen?

Providing you have room to coast and don't have anyone riding your tailgate of course.

Assume you put the Bolt in neutral, and actually coast to a stop. Say you were going 50 mph when you put it in Neutral. How ever many yards you travel, your average speed for that distance will be 25mph. Now imagine you are in D, L, or CC, going 50 mph. You wait until you are 100 feet from the stop sign, and use regen to stop. Even if you regained 100% of the energy needed to stop, it wouldn't make up for the many yards averaging 25 mph, in the previous example.

 

[Martin D]

I’ve tried both the regen mode and coasting in the D mode and I have found no difference in the efficiency between the two.

like the regen mode better than coasting in D, and that’s become my preferred setting. It now only goes into the D mode if my wife is driving the Bolt. She does not like the regen mode at all.

I would love to see my wife use any method other than the one she uses. She really likes regen/L, but she also really likes the accelerator. So it seems like she is either accelerating or slowing down. To her coasting seems to be what she mostly wants to avoid LOL

It’s a good thing that a Bolt is so efficient that it really doesn’t matter how it is driven, it’s going to use less energy than about anything else that a particular driver is going to do when they drive it.

Coasting? I usually want to visualize that as having an ocean in view 😉

 

[alexanmh]

I use both, with the goal of not totally stopping by the time the light has changed.

 

[jdunmyer]

If you're after efficiency, there's proven ways to increase it:

Accelerate gently, keep the "power' output display on the RH side of the DIC below the top of the oval. Imagine having an egg between your foot and the accelerator.

Slow down: there's a world of difference in energy used between say, 75 Mph and 60 or so. Slowing further from 60 to 50 will make some difference, but not as much as the 75 -> 60 change.

Keep your tires inflated to a bit over the recommended pressure. Watch pressure and adjust as the weather cools when Winter approaches. Tires lose about 1 PSI for every 10 degrees.

These tricks were learned long ago by drivers participating in once-popular economy runs.

 

[Zapster]

I drive in L pretty much exclusively. And when I can see waaaay ahead, I engage cruise control. It's surprisingly useful even on thoroughfares posted at 35 mph, and a quick flick of the regen paddle disengages it.

 

[Packard V8]

I would love to see my wife use any method other than the one she uses. She really likes regen/L, but she also really likes the accelerator. So it seems like she is either accelerating or slowing down. To her coasting seems to be what she mostly wants to avoid LOL

It’s a good thing that a Bolt is so efficient that it really doesn’t matter how it is driven, it’s going to use less energy than about anything else that a particular driver is going to do when they drive it.

For true. Some drivers treat the go-pedal as an ON/OFF switch. They're going to use more energy than those who drive ahead of the immediate space the car occupies, but less-so in the Bolt.

The rate of acceleration to cruising speed is immaterial, as long as it is followed by cruise. Those who accelerate faster, to a higher speed and then immediately have to slow are using more energy than if they stay in the flow, varying speed as little as possible.

It's interesting the EV6 reportedly has four modes of driving, from no regenerative braking to full regenerative braking. When I did my early test drive, I wasn't aware of this and didn't try all the possibilities.

I notice when getting into my work truck, a diesel, always unthrottled, so there's no compression braking, it's automatic to coast; when in the Bolt, it's automatic to use L mode and feather the one-pedal to best advantage.

jack vines

 

[GJETSON]

The rate of acceleration to cruising speed is immaterial, as long as it is followed by cruise. Those who accelerate faster, to a higher speed and then immediately have to slow are using more energy than if they stay in the flow, varying speed as little as possible.

Yup. I love the Bolt's CC.After slowing, or stopping, once I'm up to 25 mph, where CC will engage, it is back to CC. The Bolt accelerates briskly, without overshooting, far better than a human can do.

 

[VoltoBolt]

Coasting requires being in Neutral, which I personally would never do for many reasons.

And Coasting in Neutral does NOT turn on the brake lights, which regen in L does. I almost always drive in L.

 

[skimask]

It's more energy efficient to regen to a stop because you're adding energy back into the battery. Coasting, if you can do it, doesn't add energy back.

You will NEVER regen 100% of what you consume. Can't happen. 'cause Physics.
Coast using 0kW >> Regen'ing anything.

So this statement....127% perfectly incorrect.

Next.

 

[VoltoBolt]

If by coasting you mean driving in Neutral, I would never do it for many reasons, safety among them. Besides no brake lights on when in Neutral, but I have confirmed that they are on when I drive in L and lift my foot off the accelerator to start Regen.

FWIW: I have driven down the 5 mile Grapevine on Interstate-5 in Southern Kern County in the far right lane behind a semi driving 35 MPH (the posted speed limit for trucks) in L and CC of 35 MPH and gained 1.1 to 1.5 Kw on my gauge, and of course those 5 miles were FREE!

 

[Martin D]

For true. Some drivers treat the go-pedal as an ON/OFF switch. They're going to use more energy than those who drive ahead of the immediate space the car occupies, but less-so in the Bolt.

The rate of acceleration to cruising speed is immaterial, as long as it is followed by cruise. Those who accelerate faster, to a higher speed and then immediately have to slow are using more energy than if they stay in the flow, varying speed as little as possible.

It's interesting the EV6 reportedly has four modes of driving, from no regenerative braking to full regenerative braking. When I did my early test drive, I wasn't aware of this and didn't try all the possibilities.

I notice when getting into my work truck, a diesel, always unthrottled, so there's no compression braking, it's automatic to coast; when in the Bolt, it's automatic to use L mode and feather the one-pedal to best advantage.

jack vines

I would just be happy for any change in my wife’s method which I think is best described as a complete randomized approach. She will back-off (creating regen), re-apply acceleration and then back-off rinse/repeat without it having anything to do with anything around her going on. In her defense she is permanently disabled and has had 6 lower and now upper lumbar operations and is permanently fused from (and including the pelvic bone) all the way up to the mid thoracic. She cannot bend or twist at all. She very lucky and by Gods grace can still walk although with difficulty. So I give her a pass for not driving very smoothly. I am just glad that she is still driving in a very safe manner as she is very conservative about the speed she will go. So driving too fast is not her problem.

The average miles per kWh will drop with her driving. That is really the only problem and that means nothing to anything of importance.

 

[SteveWilson1983]

I'm using my one pedal driving to save on the brakes and also to avoid pushing on the brake pedal at a stop light.
So, what's the most energy efficient way to come to a stop? Coast or regen?

Providing you have room to coast and don't have anyone riding your tailgate of course.

Sure, coasting's better, but it will be a minimal difference. And it does also technically save on battery degradation, as you stop pulling power earler, and put less back in. Personally, I'll frequently get off the throttle early (just shift into N, unlike a gas engine, it won't rev the balls out of the motor), coast for a while, and then then come back into D or L to stop. That way I avoid the annoying portion of coasting where you travel at low speed, but also don't use the friction brakes.
Takes a time or two to get the feel for how far from a stop sign you do it at a given speed, but not hard. Am I saving much in the way of range? No.