Too much regen in D mode

[dandrewk]

Sorry, I should have picked up the "Princess Bride" reference, since I practically have that entire movie memorized.

But your example only serves to prove what I am calling "straw man" arguments:

1. At least two posters here have extolled the virtues of using "N" in lieu of a non-existent "coast" mode.
2. I respond that there is danger involved in doing this.
3. Several responders angrily counter that there is nothing dangerous at all about coast mode, claiming I must be anti-choice.

So, my point was misrepresented in order to refute it. Ergo, straw man.

 

[redpoint5]

But your example only serves to prove what I am calling "straw man" arguments:

1. At least two posters here have extolled the virtues of using "N" in lieu of a non-existent "coast" mode.
2. I respond that there is danger involved in doing this.
3. Several responders angrily counter that there is nothing dangerous at all about coast mode, claiming I must be anti-choice.

So, my point was misrepresented in order to refute it. Ergo, straw man.

I should use emoticons to defuse perceived anger in my blunt/dry style of writing.

The way in which I framed my response was a very subtle side-joke/comment underlying our discussion of danger to human life vs anti-choice.

Since we were having a straw man competition, I didn't want to be beat. :lol:

Seriously though, coast mode should be available to those who want it, and sensible use of neutral to coast is dangerous, like wearing green and yellow to a Packers game is dangerous. :roll:

 

[devbolt]

I normally use L mode when driving. I love one-pedal driving and have gotten used to it very quickly. As an experiment I went back to driving in D mode and discovered that the amount of regen in D mode is rather minimal. To me, the amount of slowing in D mode when letting off of the accelerator pedal was pretty much the same as letting off the accelerator in a traditional car, whether it was an automatic transmission or a manual. Going down a hill in D mode I either maintained the same speed, or started actually gaining speed. That certainly would not happen in L mode. More importantly, letting off the accelerator pedal while in D mode did not activate the brake lights at all unless I either hit the regen on demand paddle, or actually used the brakes.

 

[oilerlord]

Just a thought, isn't there a point where you're essentially in "neutral" with all EV's that have one-pedal driving? When I used to hypermile my VW, it's DSG transmission made slipping into neutral really easy, and did zero harm to the transmission due to it's design. I've put my EV into neutral too a few times, but it's way easier just to find the point between acceleration and regen with your right foot (I.E "neutral") instead of fumbling with a PRDNL switch to do it. I suppose the drive shaft is still engaged & spinning but it's close enough to neutral / coasting for me. For that matter, why even bother hypermiling an EV anyway? 28 kWh / 90 miles costs me a buck fifty. I can afford the extra 15 cents when it doesn't go those extra 10 miles.

Sgt, perhaps it's not best to lecture someone about safe driving while you love driving your BMW over 90, and regularly hit the 93 mph speed limiter on your Bolt. Something about the pot calling the kettle black comes to mind.

 

[GernBlanston]

...it's way easier just to find the point between acceleration and regen with your right foot (I.E "neutral") instead of fumbling with a PRDNL switch to do it. I suppose the drive shaft is still engaged & spinning but it's close enough to neutral / coasting for me.

This^^^^^^

 

[SparkE]

Just a thought, isn't there a point where you're essentially in "neutral" with all EV's that have one-pedal driving? {...} but it's way easier just to find the point between acceleration and regen with your right foot (I.E "neutral") instead of fumbling with a PRDNL switch to do it.

Yeah, it only took a few days driving my Spark EV before I figured out the 'sweet spot' on the accelerator so that I 'coast'. To verify, I glance at the main screen and it says "0 kW used" (or 2, or 4 - depending on the speed to maintain). It's only an issue 'in town' - on the freeway (or expressway) I use cruise control. Hell, I use cruise control in town a lot, if I am familiar with the location and I know there aren't a lot of stops ahead. I generally get an average consumption of over 6 m/kWh in my Spark - the exception being when I am on the freeway for a long period. Heck, even when I am on the expressway (45-50 mph) I generally get at least 5.3 m/kWh - unless it's hot. (Living in the SF Bay area, I don't have to worry too much about the cold - although the efficiency did drop rather drastically : ~5 m/kWh this past winter).

Edit: I just checked, and my current average (reported by the car and mychevy app) is at 6.2 m/kWh (since the last full charge - 300 miles ago).

 

[TimBolt]

I don't have an issue with either the "D" or "L" settings. Both work as designed and are very intuitive and easy to master.

I generally use "L" around town and "D" on the highway, and the highway coasting is fine.

I don't use the regen paddle much, I have a harder time getting that to work smoothly, probably because I'm not used to braking with my left hand rather than my right foot, but I'm sure I'll get better the more I drive.

 

[NeilBlanchard]

The VW e-Golf and the Hyundai Ioniq coast in D - and the point of having this is that it is NOT in neutral. Lift your right foot - and coast. Or, put it in a mode that has regen.

And both the e-Golf and the Ioniq BLEND regen on the brake pedal.

So, all the scary sounding machinations are moot in those cars.

On the Leaf, and the Bolt EV, shifting into N is the only way to coast, and it is totally safe. You're the driver, and if you were driving a manual transmission car, it is quite similar. Shifting back into D is very quick - and if you are driving responsibly, you will know when you will need to be in D.

If you are NOT a responsible driver, then you are in danger, no matter what "gear" you are in.

Coasting is much more efficient, and I hope that GM adds an option - switchable by the driver - to have coasting in D.

 

[oilerlord]

On the Leaf, and the Bolt EV, shifting into N is the only way to coast, and it is totally safe. You're the driver, and if you were driving a manual transmission car, it is quite similar. Shifting back into D is very quick - and if you are driving responsibly, you will know when you will need to be in D.

Coasting is much more efficient, and I hope that GM adds an option - switchable by the driver - to have coasting in D.

Coasting while "N" is selected, or at the "neutral" point on the accelerator pedal between regen & consumption is essentially the same thing (from an efficiency standpoint) isn't it? Maybe I'm missing something, but I think a switchable "coasting" option would be just as redundant as using the regen button when the brake pedal already initiates regen.

 

[ghn]

On the Leaf, and the Bolt EV, shifting into N is the only way to coast, and it is totally safe. You're the driver, and if you were driving a manual transmission car, it is quite similar. Shifting back into D is very quick - and if you are driving responsibly, you will know when you will need to be in D.

Coasting is much more efficient, and I hope that GM adds an option - switchable by the driver - to have coasting in D.

Coasting while "N" is selected, or at the "neutral" point on the accelerator pedal between regen & consumption is essentially the same thing (from an efficiency standpoint) isn't it? Maybe I'm missing something, but I think a switchable "coasting" option would be just as redundant as using the regen button when the brake pedal already initiates regen.

Coasting actually is more efficient when the slope is such that you can maintain speed in N. If in gear you would be losing speed due to the extra friction of the motor that is only be overcome by adding energy and using up some battery power. On a steep slope it is much more efficient to be in gear with the motor generating electricity and charging the battery. A really sophisticated coast system that would work in cruise control mode would probably increase MPKWH. Shifting into neutral in the right situation and then back into gear to regen could probably be done but I am not sure how much gain there would be for the effort. Certainly not something that I am planning to try.

 

[LeftieBiker]

There is no actual "shifting" with these one-speed setups. You are just turning the motor off when in "Neutral" which is also why there is no Regen.

 

[NeilBlanchard]

On the Leaf, and the Bolt EV, shifting into N is the only way to coast, and it is totally safe. You're the driver, and if you were driving a manual transmission car, it is quite similar. Shifting back into D is very quick - and if you are driving responsibly, you will know when you will need to be in D.

Coasting is much more efficient, and I hope that GM adds an option - switchable by the driver - to have coasting in D.

Coasting while "N" is selected, or at the "neutral" point on the accelerator pedal between regen & consumption is essentially the same thing (from an efficiency standpoint) isn't it? Maybe I'm missing something, but I think a switchable "coasting" option would be just as redundant as using the regen button when the brake pedal already initiates regen.

Having to feather the accelerator to coast is not nearly as effective; because it is too easy to either add power, or get regen.

An option that removed all regen from the accelerator pedal, like it is by default on the e-Golf and Ioniq, is what I am hoping for.

Blended regen on the brake pedal, and the paddle switch on the back of the steering wheel is the way to go, for efficient driving.

 

[oilerlord]

Coasting actually is more efficient when the slope is such that you can maintain speed in N. If in gear you would be losing speed due to the extra friction of the motor that is only be overcome by adding energy and using up some battery power. On a steep slope it is much more efficient to be in gear with the motor generating electricity and charging the battery.

With my VW, flipping into neutral and coasting was second nature. All hypermilers worth their salt do it. I did it all the time, but with my EV, I find it unnecessary. I can coast just as far by finding the 0 kWh point with the accelerator. No buttons, paddles, or otherwise redundant coasting options required.

Coasting "in gear" with an EV is very different than it is with a car that has an engine and transmission. By design, EVs experience very little friction losses and the power delivery is exceptionally efficient (compared with cars with legacy drivetrains) - regardless of the position of the PRNDL selector. Coast in gear with an ICE, and you're momentum is being wasted in engine braking. That doesn't happen with an EV.

So while the motor is engaged in D, I'm guessing that coasting at the point between regen and consumption is probably at least 95% as efficient as switching to neutral. Again, I agree that N is (technically) more efficient, but I'm only disputing Neil's claim that coasting in N is "much more" efficient than simply doing it with your right foot.

 

[oilerlord]

Having to feather the accelerator to coast is not nearly as effective; because it is too easy to either add power, or get regen.

An option that removed all regen from the accelerator pedal, like it is by default on the e-Golf and Ioniq, is what I am hoping for.

Blended regen on the brake pedal, and the paddle switch on the back of the steering wheel is the way to go, for efficient driving.

100% agree on that. It is too easy to add power or get unwanted regen when all you want to do is coast.

Personally, I'd rather switch off 1-pedal driving altogether, and just have the car coast when I lift off the accelerator. Much easier to modulate the amount of regen (you want) through the brake pedal.

 

[GetOffYourGas]

There is a lot of confusion on this thread.

<span>On the <a href="http://www.mynissanleaf.com" class="interlinkr">LEAF<span class="tip">Visit the LEAF Forum</span></a>, and the Bolt EV, shifting into N is the only way to coast, and it is totally safe. You're the driver, and if you were driving a manual transmission car, it is quite similar. Shifting back into D is very quick - and if you are driving responsibly, you will know when you will need to be in D.</span>

Coasting is much more efficient, and I hope that GM adds an option - switchable by the driver - to have coasting in D.

Coasting while "N" is selected, or at the "neutral" point on the accelerator pedal between regen & consumption is essentially the same thing (from an efficiency standpoint) isn't it? Maybe I'm missing something, but I think a switchable "coasting" option would be just as redundant as using the regen button when the brake pedal already initiates regen.

You are correct that the consumption would be the same thing, if gyou were to feather the accelerator such that there is zero power / zero regen. While possible, that's really hard to do for any length of time. I would even argue it's "impossible" for a human to do in a Leaf. There is no play between power and regen - you'd have to find the exact spot where the power is zero, and hold it there without moving a muscle. The instrumentation is not good enough to tell you where that is, and doing it by feel isn't realistic either. Does the Bolt offer some play in the zone between power and regen? I honestly don't know, I didn't try it when I did test drive one.

I'm with Neil 100%. The car should have a mode in which there is zero regen with your foot off both pedals. It doesn't have to be the default, but it should be readily available. It's just software. Really. And then this thread would be about our own personal favorite modes, and not trying to convince each other that those modes should or shouldn't be available because they are "redundant" or worse, "unsafe".

 

[oilerlord]

I'm with Neil 100%.

Me too. Read my last post. I think we all want the same thing.

 

[GetOffYourGas]

I'm with Neil 100%.

Me too. Read my last post. I think we all want the same thing.

Your last post slipped in right before mine. I didn't see it when I wrote that.

 

[SeanNelson]

...it's way easier just to find the point between acceleration and regen with your right foot (I.E "neutral") instead of fumbling with a PRDNL switch to do it. I suppose the drive shaft is still engaged & spinning but it's close enough to neutral / coasting for me.

This^^^^^^

BUT - it would be EVEN EASIER if there was a "coast" option you could set so that all you need to do is lift your foot from the accelerator completely. No hunting around for that point between "accelerate" and "decelerate". The accelerator pedal would ONLY be pressed if you want to accelerate, and it would never cause active deceleration over and above that caused by wind resistance, grade, etc. If you want to actively decelerate, you either use the brake pedal or the regen paddle. No fiddling with the "shifter", just a simple user preference that you'd configure once in the setup menu and then be done with it.

 

[oilerlord]

BUT - it would be EVEN EASIER if there was a "coast" option you could set so that all you need to do is lift your foot from the accelerator completely. No hunting around for that point between "accelerate" and "decelerate".

Interesting thought. I'm surprised no one else came up with that, as the the answer was right in front of us. Thanks Sean!

 

[NeilBlanchard]

I hope the GM (and Nissan) are listening! Coasting in an electric car is a wonderful thing - no idling.

Oilerlord - VW and Hyundai have done it right!

If you get a chance to drive a VW e-Golf (or an Hyundai Ioniq) to see what coasting by default is like - take it! The e-Golf also has adaptive creep - it has no creep by default, and adds a bit after you do a couple of stop and go movements in traffic. All in all, VW has done it right.