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I have a 2018 volt, and so far I like it a lot. Question about regenerative braking: Is the regenerative braking in L-mode additive?
I prefer to drive the car in L-mode, which lets me control the amount of generative "engine" braking with the gas pedal. Often that is not sufficient and I use the steering wheel paddle to increase the braking action. And, of course, if that is not enough I use the brake pedal.
I assume that the "engine" braking (just letting off the pedal), and the steering wheel paddle are the same thing, just use the motor as a generator. But what happens when I then step on the brake pedal in addition? Will that add to the generation, or will it then simply use the breaks to waste energy?
I am just interested in maximizing my regeneration. Does braking with the pedal help?

Inquisitive minds want to know ...
 

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Only the lightest touch on the brake pedal with LOW and PADDLE engaged will give slight additional regen--but it's such a minimal amount that it's not worth the trouble learning how to feather it just right. You cannot get more than -60KW in regen and that is only with some friction brakes applied (not sure why, but that's my experience). In general, the max you can expect is -50KW for max regen, but that's usually only achievable when using max regen at highway speeds.

Put the Volt in Classic Enhanced and use the "leaf ball" on the left hand side to show you when you're using friction brakes instead of regen--it starts to get a strong yellow (it will slightly yellow on heavy regen with paddle + low). Honestly, I wished they had made it remain all green like the Gen 1 unless and until you start using friction brakes.
 

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"Is the regenerative braking in L-mode additive?"
Sure is for me on a gen 1
I use that mode 99 % of the time -- the other 1 % is rev and P -- and what ever that N position is for.
 

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Your goal should be to employ regen as a braking technique, not as a recharging technique.

Regenerative braking is an alternative to friction braking available in electric cars. The main purpose of regen is to slow the car down, just like the friction brakes do. Prolonging the life of the brake pads and drums is a bonus. Putting some charge back into the battery is a bonus, too.

My understanding is that GM implemented regenerative braking in the Volt such that it’s difficult to avoid creating regen without shifting into Neutral. Otherwise there’s a light level of regen when coasting in D, a stronger fixed level when coasting in L. Pulling on the paddle will add a certain fixed amount to either D or L. With a Gen 2 Volt, easing off the accelerator can initiate application of negative torque (regen).

GM also allows you to use the brake pedal to engage and modulate the regenerative braking system in the same way you would engage the friction brakes in a gas car. Friction braking is "blended in" when the pressure you put on the pedal is asking for more "stopping power" than regen can deliver, such as for a panic stop, or for stopping the car below ~5 mph.

Level terrain regen captures some of the energy previously used to accelerate the car to the current speed. Energy used to maintain speed is irrecoverable. I suspect that the quantity of regen created when you slow from 40 mph to 20 mph or from 35 mph to a stop doesn't depend on the regen level. Higher regen levels slow the car faster, generating higher levels of regen for shorter periods of time.

Normal driving conditions require you to slow down or to stop from time to time (e.g., the traffic light ahead changes to red) and then accelerate back up to speed. The "bonus" is that because regenerative brakes capture some of that energy previously used to accelerate, each repetition of "slow down, speed up" reduces the "per episode average" amount of energy used for accelerating back up to speed. Any energy used to accelerate "back up to traffic flow speed," however, is far more productively used to maintain speed.

If you minimize regen by minimizing the number of times you need to "accelerate back up to speed" and minimizing the amount you decelerate before the light changes (by starting your coast sooner in D to stretch out coasting time, giving the light more time to change) you keep even more of your battery power for use in maintaining speed...

And perhaps it should also be mentioned that you don’t need to be running on battery power to create regen when you slow down/drive downhill. You’ll drive many regen-battery-powered miles that are recorded as "Gas Miles."
 

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Yes they do.
They'll also come on in L when you're off the throttle. As far as I can tell anytime the 2nd Gen Volt is slowing down faster than a standard ICE car the brake lights come on.
 

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Bear in mind, any regeneration is a fraction of the energy used to get momentum so should not be used when momentum can be safely maintained, other wise GM would have invented the perpetual motion machine. Regen is not the cake, it's just the icing on the cake.
 

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Mine seems like it's additive but I can't be certain. I'm heading out in a few minutes so I'll see if there's a way I can test.

On another, but related note, does anyone else have inconsistency in the amount of regenerative braking while using the paddle? Mine is inconsistent leading to a jerky slowing experience when using it. Braking in L seems to be consistent.
 

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On another, but related note, does anyone else have inconsistency in the amount of regenerative braking while using the paddle? Mine is inconsistent leading to a jerky slowing experience when using it. Braking in L seems to be consistent.
Yes -- but make sure you don't lessen your grip at all to be certain. There is a slight "pause" in regen when first engaging and then there is an occasional (but still noticeable) "pause" in the regen at certain low speeds. It also "shuts off" when you've slowed to less than 5 MPH (or when the momentum of the car is no longer providing regen).

Make sure you keep tabs on the KW usage to get a better sense of how much regen you are getting, it will help you to "learn" the best techniques to maximize it when you have to.

As a former Gen 1 owner, the paddle is an excellent tool in my heavy stop & go area. I think it's recapturing quite a bit more energy I ended up losing in my Gen 1 despite driving in L exclusively.
 

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On another, but related note, does anyone else have inconsistency in the amount of regenerative braking while using the paddle? Mine is inconsistent leading to a jerky slowing experience when using it. Braking in L seems to be consistent.
Braking in 'L' is a fixed amount - A certain percentage of the maximum possible. Pulling the lever gives you the maximum possible, but that amount varies depending on your speed and the amount decreases as your speed decreases

I drive pretty much the same way you do - In 'L' most of the time (all the time except on high speed roads) and when I lift to slow, I add some paddle near the end if L isn't slowing me quickly enough. I time the paddle to where I release it just as the car comes to a stop, so there's no jerky motion. With practice, you'll get much smoother

Don
 

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Braking in 'L' is a fixed amount - A certain percentage of the maximum possible. Pulling the lever gives you the maximum possible, but that amount varies depending on your speed and the amount decreases as your speed decreases

I drive pretty much the same way you do - In 'L' most of the time (all the time except on high speed roads) and when I lift to slow, I add some paddle near the end if L isn't slowing me quickly enough. I time the paddle to where I release it just as the car comes to a stop, so there's no jerky motion. With practice, you'll get much smoother
Typically I am driving in D and not L. I only switch to L when I expect significant stop and go driving.

Thanks to all those who replied about this.
 

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Discussion Starter #13
Yes, thanks to everybody. I tested it today, and my impression is that when I coast in D and then pull the paddle, the transition is too strong. It's like stepping on the break, without being able to modulate the breaking to a lower level. I don't like that.

Driving in L allows me to coast with no breaking or acceleration (takes a bit of practice, especially in Sport mode), and I can modulate the braking depending on how much I let off the pedal. and when that is not enough I can pull the pedal and increase the braking, and use the pedal if I need even more.

It seems to me that just letting off the pedal in L applies a certain amount of regenerative braking, using the paddle adds to that, and using the pedal can add a bit more. Not sure how much that is, but I estimate 40-40-20%.
 

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L, paddle, and pedal are all additive methods of regen. When the Driver Efficiency Gauge is completely filled in you are then using friction brakes (brake pads) to slow beyond that point. And I believe the "light ring" on the modern display turns yellow to indicate friction braking has been reached.
 
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