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I was curious what the efficiency difference is between driving with D vs L so I created a spreadsheet. For my 9.5 mile morning commute in Austin mostly at highway speeds I made a note of few things I thought might be relevant. The "mi/kWh Disp" column is the value displayed at the end of my commute (I reset it each morning). The "mi/kWh DA" column is my attempt to figure out the mi/kWh only due to driving and accessories by dividing by the "DA" column, which I got from the efficiency information. I excluded one data point where I had the seat heater on since I'm not sure how that's accounted for.

Although the result, which is in the last two rows, does not show a statistically significant difference I think that my commute is too short. A longer commute would better control for variations due to the initial heating and cooling. Still though it seems there is not a big difference. Maybe preference matters more than efficiency.

I've attached a screenshot of my spreadsheet.
 

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I'd guess that you're right about preference rather than than any real difference.

On the freeway (non-stop&go), there's relatively fewer occasions to decelerate. If you keep a long distance between you and the car in front, you can anticipate slow-downs and let the car regen gradually in D and recover just about the same amount of energy as a shorter, more aggressive regen period in L.

I commuted on an electric motorcycle for 25 to 50 miles for 4 years. About half of any day's mileage was on-the-job in the the steep terrain of San Francisco, with lots of stop/starts. I noticed that the range was improved by using the "Sport" setting with its more aggressive regen curve than the milder "Normal" mode. I think this usage case varies sufficiently from your flat, mostly freeway trips to make the more aggressive regen not so much a factor in your case.

I find I do prefer the D setting for the freeway, so my speed adjustments are smoother. In the city, L all the way, baby!
 

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If you keep a long distance between you and the car in front, you can anticipate slow-downs and let the car regen gradually in D and recover just about the same amount of energy as a shorter, more aggressive regen period in L.
I don't understand why people keep assuming that "L" mode is more efficient or less efficient because of its greater regen capability. Yes, if you use regen more often or more aggressively you'll tend to be waste power because regen isn't 100% efficient and you end up having to speed back up again anyway. But just because "L" mode can regen more aggressively doesn't mean that it has to regen more aggressively.

I use "L" mode all the time and I slow down early and gradually in order to avoid wasting power. There's no reason the car is going to waste any more power in "L" mode than in "D" mode if you drive the same way in both modes. Decelerating at 0.1g in "L" mode with your foot lightly on the accelerator pedal isn't any different than decelerating at 0.1g in "D" mode with your foot lightly on the brake pedal, it's just a different way to command the car to do the same thing.

IMHO the great thing about "L" mode isn't that it can come to a fast stop, it's that you can drive without having to move your foot back and forth. It means you can make very smooth and gentle transitions between acceleration and deceleration without having to go through a "dead" transition as you move your foot from one pedal to another.
 

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I use "L" mode all the time and I slow down early and gradually in order to avoid wasting power. There's no reason the car is going to waste any more power in "L" mode than in "D" mode if you drive the same way in both modes.

Good info. But, as you state, there IS a learning curve. You have to learn how to "slow down early and gradually". IF you are in "L" and want to slow to a stop, you recapture some (most?) of the kinetic energy as "regen". If you wish to stop at a specific place (such as at the end of a line of cars) and it slows you such that you need to re-accelerate to get there, did you expend more energy to do so than you had recaptured? If you had been in "D" and coasted to the point of stopping, would you have "spent" less energy than if you followed scenario #1 above?
 

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My guess is any differences are very dependent on driver skill, although I would guess that if the driver uses L and is an expert that might produce the best results. I just prefer drive and regen, which doesn't require as precise operating of the accelerator as L. For me, the main thing that kills mileage is creeping up to 70 or 75 mile per hour, when on the freeway.
 

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Many of these small differences don't matter a hill of beans to 99% of drivers. Most of us (including myself) DO drive less than 40 miles RT on a usual day. For those days, I simply drive like I do any ICE car. I recharge at night when I get low, and do not have to worry about whether "D" or "L" is more efficient. The Leaf is going to sell like hotcakes since it WILL meet the range needs of 99% of single day drives, and cost much less. The workmanship is up to Nissan standards (good in my opinion). It is just for those of us who want to make that 235 mile drive to the next DCFC, without TOO much anxiety, that all the little tweaks (and having a Bolt instead of a Leaf) matter. And I agree, slowing down as much as practical (not possible) has the single greatest effect on range. Keeping your max speed <60 mph makes a 250 mile range fairly routine. And if you stay off the interstate and drive 45 mph, you can push it up to 299 (or as long as your bladder can hold out).
 

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If you wish to stop at a specific place (such as at the end of a line of cars) and it slows you such that you need to re-accelerate to get there, did you expend more energy to do so than you had recaptured? If you had been in "D" and coasted to the point of stopping, would you have "spent" less energy than if you followed scenario #1 above?
I dunno, this just doesn't seem like rocket science to me. Back in the days of "two pedal driving", was misjudging the braking distance really a widespread problem? When using the brake pedal did lots of people really slow down too quickly and then have to use the gas pedal to get to the place where they wanted to stop?

One pedal driving isn't really any different - you look out the window as you're decelerating and with any driving experience at all it's pretty easy to see if you're going to stop short or long. If you're going to stop short, you apply a little more pressure to the pedal - that doesn't necessarily mean "more gas", it usually just means "less regen". It doesn't matter and you don't have to think about it because you don't need move your foot from one pedal to the other to choose between the two. And if you're going to stop long, you ease up a bit - same thing - no need to think about it, just "press harder to stop further or lighter to stop closer".

It takes a lot of words to describe, but I find that it's really very intuitive. The key here is that being able to stop quickly in "L" mode doesn't mean you have to stop quickly. You do those long, gradual stops just as easily in "L" as in "D" - in fact I'd argue that it's easier in "L". It's really a matter of driving style, not what mode you're in.
 

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If you wish to stop at a specific place (such as at the end of a line of cars) and it slows you such that you need to re-accelerate to get there, did you expend more energy to do so than you had recaptured?
There's no inherent reason "L" would stop short of the desired spot other than the driver did not properly use the capabilities of the vehicle. Just as it's torture to ride with an ICE driver who is constantly on and off the throttle, it's not much fun to ride with an EV driver who doesn't use decel to best advantage. Aware drivers who understand the capabilities of their vehicle and who moves with the flow of traffic, watch far ahead, have good spatial awareness, will always expend less energy than those who don't.

jack vines
 

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Just as it's torture to ride with an ICE driver who is constantly on and off the throttle, it's not much fun to ride with an EV driver who doesn't use decel to best advantage.
Yeah, I get the impression that a lot of people who talk about the "inefficiency" of "L" mode might be those kind of "digital" drivers who treat the brake and accelerators pedals as if they're "on/off" switches - either full acceleration or full braking. Good driving is, IMHO, a lot more nuanced that - it doesn't matter whether you're in "D" or "L" mode.
 

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Seems no one has taken into consideration wear and tear on the brakes. I drive almost exclusively in "L" and use the regen paddle while the car is slowing in "L" if I under estimate the stopping distance. I usually can drive all day and use the brakes once or twice. I'm very confident that I will never have to replace the brakes unless I keep my Bolt for 100,000 miles. Driving in "D" and using the regen paddle might have the same results as far as having to use the brakes, but would a lot harder to do. If you are looking for the overall efficiency of which mode to drive in, consider the wear and tear on your brakes also.
 

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I'm very confident that I will never have to replace the brakes unless I keep my Bolt for 100,000 miles.
I drive the same way and I'm pretty sure we'll *never* have to change the pads. The brake fluid, maybe.
 

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I noticed that the range was improved by using the "Sport" setting with its more aggressive regen curve than the milder "Normal" mode.
What "more-aggressive regen curve"? I've never seen anything that supports this assertion.
 

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I prefer 'L' mode because it gives me greater control over braking, and maximizes my regen braking. In my early days of driving my Bolt, I tried both 'D' mode and 'L' mode. I found I was hitting the brakes much more frequently in 'D' mode. And I didn't know about the steering wheel paddle at the time. I wonder if selliott512 was using the regen paddle. If he was using it, all of his calculations are moot.

I punch it a lot in my Bolt. My electrical energy is so cheap, there is little point in 'hypermiling'. Yet, I'm still getting around 3.5 miles per kWh from my LT.
 

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D or L the amount the regen brakes are used should be pretty close to the same. The brakes on the Bolt are linear in progression. On another thread somewhere there is a good illustration of how this works but the simple explanation is this. No matter which mode D or L the Bolt uses 100% of the available regenerative braking capacity available (that changes based on multiple factors) before the mechanical brakes are engaged. That is why many people report the brake pedal feeling mushy. Driving in D or L is just a how do you want the Bolts pedals to behave type of thing. D is a more traditional behavior you would relate to an automatic car, that is letting off the "gas" pedal will slow you some but not a lot, engine drag/braking. This means you have to hit the brake pedal (or regen paddle) to get the expected braking behavior, but the Bolt still uses the Regen braking to its full capacity first and then engages the physical brake. Whereas driving in L shifts to a mode where letting off the accelerator applies a much larger percentage of the regen braking capability from the start. Not quite 100%, you get that with foot off the accelerator and regen paddle or some pressure on the brake pedal.

If there are efficiency gains in driving in L it will probably just be from the fact that doing it that way gives you more direct and precise control. Thus it is easier to learn the amount of pedal travel to get the expected results.
 

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Yeah, I get the impression that a lot of people who talk about the "inefficiency" of "L" mode might be those kind of "digital" drivers who treat the brake and accelerators pedals as if they're "on/off" switches - either full acceleration or full braking. Good driving is, IMHO, a lot more nuanced that - it doesn't matter whether you're in "D" or "L" mode.
I'm one of those digital drivers. Only one of my passengers have ever took note but I'm curious, how bad is the on/off behavior to passengers?

Seems no one has taken into consideration wear and tear on the brakes. I drive almost exclusively in "L" and use the regen paddle while the car is slowing in "L" if I under estimate the stopping distance. I usually can drive all day and use the brakes once or twice. I'm very confident that I will never have to replace the brakes unless I keep my Bolt for 100,000 miles. Driving in "D" and using the regen paddle might have the same results as far as having to use the brakes, but would a lot harder to do. If you are looking for the overall efficiency of which mode to drive in, consider the wear and tear on your brakes also.
I don't think the brakes will wear like you think. Bolt uses regen braking when you press the pedal and only at some defined point in brake travel or deceleration Gs does it start blending in the physical brakes. Even with the physical brakes engaged, if the motor is available to regen I think the Bolt still uses it to add to the combined braking force.
 

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I'm one of those digital drivers. Only one of my passengers have ever took note but I'm curious, how bad is the on/off behavior to passengers?
It's not much fun. Passengers have no steering wheel to hold onto and they don't get to anticipate when you'll lurch the car forward or stop the lurch. But some cars drive smoother than others, so it depends.

Do you adopt this all-or-nothing strategy when doing other things? Pouring milk on your cereal in the morning you turn the carton upside down for maximal flow and then flip it back upright. The volume on your TV is cranked up to the max but you mute it when it becomes too much. At work you work like crazy and then freeze with a zoned out look on your face for a few moments before resuming your frenetic pace. And when it comes to relationships… well, let's not even go there. ;)
 

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quirkySquirt said:
...how bad is the on/off behavior to passengers?
It's just not necessary and it's uncomfortable for no reason. As a professional pilot,
I have an obsession with being smooth in my driving just like flying. It costs nothing,
it's easier on the equipment, and the passengers appreciate it. And it's a fun game to play.
 

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I have an obsession with being smooth in my driving just like flying. It costs nothing, it's easier on the equipment, and the passengers appreciate it. And it's a fun game to play.
My memory of train travel is that you can never tell exactly when the train has started moving except by looking out the window. I try to replicate that experience by feeding in power very slightly at first, then ramping it up smoothly until the acceleration is fairly pronounced, and then easing it off again as I approach the target speed. The goal is for the passengers to never be aware of exactly when acceleration has started or ended, and to be able to adjust to it as it changes.
 

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My memory of train travel is that you can never tell exactly when the train has started moving except by looking out the window. I try to replicate that experience by feeding in power very slightly at first, then ramping it up smoothly until the acceleration is fairly pronounced, and then easing it off again as I approach the target speed. The goal is for the passengers to never be aware of exactly when acceleration has started or ended, and to be able to adjust to it as it changes.
 
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