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Several posts have convinced me D and L use approximately the same number of KWh. But, do they regenerate the same? In other words, do you get better range with one over the other?
 

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There has been no scientific tests done or reported here, but I have had some discussions with a Bolt engineer. His short answer, "The prime directive has always been, 'No compromises, no thinking required on the part of the owner.'" Drive in D. slight regen and then and you'll have to use the foot brake, which maxes regen first before friction. Drive in L and it maxes regen until you use the paddle or the foot. The resulting range should be the same.

jack vines
 

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PhD answer... it depends. :)

Factors:
  • Rregen results in net energy loss... more regen in L.
  • Friction braking results in energy loss... this happens more in D.
 

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Several posts have convinced me D and L use approximately the same number of KWh. But, do they regenerate the same? In other words, do you get better range with one over the other?
The only reason there would be any difference is if you sometimes used the hydraulic brakes in "D" mode. That would happen if you try to brake too aggressively for regen to deal with. One of the nice things about "L" mode is you know for sure that you're not using the hydraulic brakes as long as you don't put your foot on the brake pedal.

Beyond that, you driving style and other external conditions (traffic, elevation changes, temperature, etc.) will have a lot bigger impact on range then anything else.
 

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If you get worse range in L mode you will also get car sickness from deceleration. Range will be the same, probably better for most drivers. Regen is much stronger in L.
 

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I'm not sure I believe that the range in D is the same in L. I've been doing some anecdotal experimentation with my 168 mile commute each day. Seems that with my mostly highway commute, I get better range in D rather than L.
 

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I'm not sure I believe that the range in D is the same in L. I've been doing some anecdotal experimentation with my 168 mile commute each day. Seems that with my mostly highway commute, I get better range in D rather than L.
If you have elevation changes, then I would think D would have better range by avoiding any heavy regen. As great as regen is, it has some losses. Only advantage to L is that it would possibly maintain speed better on steep declines.
 

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I believe that the difference is negligible. After 2 years, 8 months of Bolt ownership, I have not been able to establish a consistent measurable difference. So, even if there was a difference, it's not measurable in my real world.
 

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If you have elevation changes, then I would think D would have better range by avoiding any heavy regen.
You don't have to regen any more in L mode than you do in D mode. If you choose to slow down in L mode more than you would in D mode, that's your choice - it's not something L mode somehow forces you to do.
 

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You don't have to regen any more in L mode than you do in D mode. If you choose to slow down in L mode more than you would in D mode, that's your choice - it's not something L mode somehow forces you to do.
Agree, but if you're on a long commute you'll most likely be using the cruise control. The cruise control will aggressively maintain speed. Which I like, but would assume that it would potentially waste some energy over time in L vs D by using slightly more regen to maintain speed on downhills.
 

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With inflation, my 2 cents of opinion are worth only 1.1 cents, but here goes. If, when driving (and coasting) in "D", you do NOT use the regen paddle and ONLY use your friction brakes, you will get less range. IF you incorporate the paddle as a hand brake for all deceleration, the range should be the same. The starting energy in the battery is the same. Kinetic energy (from velocity) is the same. Potential (gravitational) energy going up and down hills is the same.
 

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Reiterating the more important point... driving in L is much safer. When you need to do an emergency stop, your car slows down once you lift your foot from the accelerator and reach for the brake, increasing the braking time to slow the car. Also, in L mode, if something medically bad happens to the driver, the car stops instead of ramming into something.
 

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Agree, but if you're on a long commute you'll most likely be using the cruise control. The cruise control will aggressively maintain speed. Which I like, but would assume that it would potentially waste some energy over time in L vs D by using slightly more regen to maintain speed on downhills.
If the cruise control set point is the same then the amount of regen used will be the same. "D" vs "L" mode doesn't magically change the amount of energy that needs to be recouped to control downhill speed. There would only be a difference if cruise control in "D" mode allowed the speed to rise significantly above the set point, and to the best of my knowledge that doesn't happen.

If, when driving (and coasting) in "D", you do NOT use the regen paddle and ONLY use your friction brakes, you will get less range.
My informal experiments maintaining speed going downhill in "D" mode and using the brake pedal vs using "L" mode and not touching the brake pedal have led me to believe that "D" can produce the same amount of regen that "L" does. If the hill is steep enough, you might exceed the car's capacity to regen in "D" mode and end up engaging the friction brakes without realizing it, but then you'd have to do the same to maintain the same speed in "L" mode anyway. And I've found precious few hills steep enough for that to happen.
 

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My informal experiments maintaining speed going downhill in "D" mode and using the brake pedal vs using "L" mode and not touching the brake pedal ...
Did you mean "pedal" or "paddle"? This makes a difference. Here in WV, we have many hills and I can traverse most of them using the paddle and never touching the pedal. Of course, every time you use the pedal, you lose energy as heat, even if the "pedal" introduces slight "regen".
 

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Reiterating the more important point... driving in L is much safer. When you need to do an emergency stop, your car slows down once you lift your foot from the accelerator and reach for the brake, increasing the braking time to slow the car. Also, in L mode, if something medically bad happens to the driver, the car stops instead of ramming into something.
Yes, good point (even if not on topic LOL).
One of the main reasons I like that my mother uses L mode. She's a good driver, but reflexes arent the best once one is beyond 70 yrs and L mode gives me more peace of mind for her. Plus she loves it of course, it's a great way to drive IMO.
 

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Did you mean "pedal" or "paddle"? This makes a difference. Here in WV, we have many hills and I can traverse most of them using the paddle and never touching the pedal. Of course, every time you use the pedal, you lose energy as heat, even if the "pedal" introduces slight "regen".
I meant "pedal". My point was that from what my unscientific trail runs down hills I found when you use the brake pedal (the one you push with your foot) in "D" mode you can get as much regen as you do in "L" mode. It's not just "slight", it appears to be equivalent. So I don't really believe that "D" mode is any less efficient unless you need to apply so much braking force that it exceeds the regen range of the pedal and starts using the friction brakes. I only have to brake that hard very, very rarely, so it's basically a non-issue.

That all having been said, I still drive in "L" mode all the time because of the great driving experience it gives me.

You can try it yourself on the hills you travel on - do it in "L" and note the amount of regen that's being displayed on the power meter, then do it again in "D" using the brake pedal and see if you're getting the same amount. It's only an approximate read, of course, but when I do it I see very similar amounts of regen.
 

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Yes, good point (even if not on topic LOL).
One of the main reasons I like that my mother uses L mode. She's a good driver, but reflexes arent the best once one is beyond 70 yrs and L mode gives me more peace of mind for her. Plus she loves it of course, it's a great way to drive IMO.
Is this her? :)

 

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I agree with Sean, you can get the car to do the same with both, the only difference is what your feet are doing. Whichever you are more comfortable with and are smoother with is the one you will do better with. I personally tend to use D more of the time than L.

I like to try to predict high risk situations and hover my foot over the brake pedal, this is a habit. I cannot do this in L mode so it makes me uncomfortable in those situations. I'm not going to say its any safer or more dangerous than another guy using L, its just more comfortable for ME. You gottta figure out which works for you..
 
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