Power consumption when stopped in Drive

[Chrisstoneham]

My car does the same. It is useful when in a traffic queue. My brake lights are "on" even though my foot is not on the brake.

 

[Chrisstoneham]

My car does the same. It is useful when in a traffic queue. My brake lights are "on" even though my foot is not on the brake.

 

[Ancient1]

No - that's exactly what it was designed to do. E-pedal gives you an anti-creep function that keeps the car from moving until the accellerator is pressed. I drive in B range with e-pedal always on, and I love the control it gives me. I rarely need to use the brake pedal, even in a hilly area such as I live in.

 

[benjwhite9]

I have a 2020 S Plus I drive with the epedal in D when I come to a stop I take my foot off the brake and my car never moves, creeping or otherwise even if downhill. I just sits there until I press the accelerator. Does that mean there is something wrong with my car?

I believe that is the correct behavior.

Never mind, there was a page refresh issue. Others have already made that point.

 

[Bombastinator2]

Hi, I was wondering how much power/amps is being drawn when stopped in "D"rive.
Because, just like in an ICE automatic, you feel a pull, and if you let go of the brakes the car will slowly move forwards.
This seems to be an engineered behaviour, to resemble de feel o a regular automatic. which I admit is very well done.
A regular driver, would probably not know he is driving an ev, if not for the torque.

So I was wondering, is this "on" all the time (which may seem a power wastage), or they have cleverly engineered it that the moment you lean off the break the motor kicks in? However, it doesn't feel that it does this.

Would anybody know the answer?
Maybe plugging a scanner into the ODB port will show up more useful info (like actual amps going in/out of the battery)

Derek.

Well, it’s electric, so unlike an ICE engine, the only way to spend power is to move or run anticilliaries such as a heater or the AC. I once ran about a quarter of my main battery down while just sitting there but I did it with multiple hours of climate control use. If I was in an ICE car I would have had to have the engine idling. The heater core of an ICE car is really just a small engine radiator

 

[Bombastinator2]

I read somewhere on this forum that when in drive (and B mode) and stopped, there is a fairly sizeable draw on the battery. As I recall, it was around 1,300 Watts. The energy use screen does not show this. That's why some people shift into neutral while stopped.

Remember laws of thermodynamics still apply. If that much energy was being used something was getting really hot. The heater would do it.

 

[Bombastinator2]

The ePedal system was first introduced in 2018 and is only available on the generation 2 LEAF.

Really?! I assumed it was some sort of awful legacy thing or something. When it’s on you can’t coast. I find in city driving it absolutely eats battery. Like a 15% hit. I never use it.

 

[Ancient1]

Really?! I assumed it was some sort of awful legacy thing or something. When it’s on you can’t coast. I find in city driving it absolutely eats battery. Like a 15% hit. I never use it.

And why would you want to coast? You have no control that way, other than with your brake pedal. How are you determining that e-pedal is affecting your range in a negative manner? I can find nothing that would give me that impression, either on the Leaf itself or on LeafSpy. Where did you get your 15% figure? Using e-pedal, I feel that the extra control it provides is very beneficial, and I love the ability to do one-pedal driving, with virtually no use of the brake pedal at all.

 

[Jerther]

Some people find ePedal mode tends to apply physical brakes too early for their driving style. Physical brakes are 100% loss in efficiency. AFAIK there's no way of knowing when the physical brakes are applied when in ePedal mode and so it's extremely difficult to modulate braking to optimize efficiency. But without ePedal, it's only regen braking and the physical brakes aren't applied until you actually depress the brake pedal.

By the way, even regen braking is not 0% loss. IIRC someone here did some tests (can't find the thread) and concluded it's around 15 to 20% loss, so it's only 80-85% of the regen energy that actually makes it into the battery. So all in all, it's best to coast without any brake or regen. But then you might exceed the speed limit. There are tradeoffs.

It's nice that we get to have all combinations of ePedal, D, B, and Eco. To each his own and everyone wins.

 

[BillAinCT]

Some people find ePedal mode tends to apply physical brakes too early for their driving style.

It also applies regen earlier in D mode. I find it much easier to coast or slow without regen or braking in e-Pedal B mode. As if the "coast window"is larger in B over D. I also find regen is less strong in B mode, which I prefer, since I can more easily coast to a light and when near and slowly apply regen. My efficiency is definitely better since switching to B instead of D. But some of the time I simply forget to double shift.

 

[Jerther]

It also applies regen earlier in D mode.

Interesting. I'll have to check that!

I also find regen is less strong in B mode

Now that's weird. Isn't B mode precisely and only for stronger regen?

I found these:

https://mynissanleaf.com/threads/62kwh-leaf-plus-efficiency-posting.29971/page-8#post-581422

https://mynissanleaf.com/threads/wh...mental-to-efficiency.33286/page-2#post-645594

 

[woeful]

AFAIK there's no way of knowing when the physical brakes are applied when in ePedal mode...

There's no way of knowing when the friction brakes are applied when pressing the brake pedal, either. LEAF brakes use regen for gentle braking, and add in the friction brakes, seamlessly if it all works, when more slowing is needed than regen can provide.

Without ePedal, either B or D mode provide some pure regen; ePedal adds friction braking just when needed for the amount of slowing-down deceleration desired.

 

[Drew21]

I also find regen is less strong in B mode, which I prefer, since I can more easily coast to a light and when near and slowly apply regen.

I'm also confused by this statement, although perhaps this is a difference between a newer Leaf with e-Pedal vs our 2014.

In the 2014, regeneration in D mode will light up only one or two of the four regeneration bubbles on the dashboard. Regeneration in B mode will light up all four regeneration bubbles. You can also see the difference on the energy-use screen in the center dash, with regeneration in D mode pushing roughly half as much kW back into the battery as regeneration in B mode. Also, you can definitely feel the difference between D and B regeneration.

 

[LeafNissan1]

I'm also confused by this statement, although perhaps this is a difference between a newer Leaf with e-Pedal vs our 2014.

It also applies regen earlier in D mode. I find it much easier to coast or slow without regen or braking in e-Pedal B mode. As if the "coast window"is larger in B over D. I also find regen is less strong in B mode, which I prefer, since I can more easily coast to a light and when near and slowly apply regen. My efficiency is definitely better since switching to B instead of D. But some of the time I simply forget to double shift.

The e-Pedal is definitely less efficient from my experience in both my 2022 Leafs, which I assume could only be explained due to more mechanical braking. Regen is much more aggressive in B mode when coming off the accelerator than in D and the so-called "coast window" is much narrower in B than in D. I use many hyper-mileing techniques and always driving in B mode give me the best m/kWh.

 

[Bombastinator2]

And why would you want to coast? You have no control that way, other than with your brake pedal. How are you determining that e-pedal is affecting your range in a negative manner? I can find nothing that would give me that impression, either on the Leaf itself or on LeafSpy. Where did you get your 15% figure? Using e-pedal, I feel that the extra control it provides is very beneficial, and I love the ability to do one-pedal driving, with virtually no use of the brake pedal at all.

It’s how I drive. When you coast you move but don’t use power. It’s kind of a big deal in really urban driving when there are lights everywhere and you are forever slowing down. If you take your foot off the “gas” when the light turns red and coast to the light, you get the distance to the light as free movement. Furthermore pushing a car from full stop uses more power. If you get a bit lucky, the light turns green when you are still coasting in and you never completely stop at all even though you aren’t going very fast.

I got it from comparing my “efficiency” of miles per kilowatt with and without it. It was a good bit higher without it. Remember, regen isn’t super efficient, but coasting is 100% efficient by definition.

I initially assumed it was more energy efficient but was shocked to discover it not only wasn’t it was a lot worse. If this isn’t the case for others perhaps I am doing it wrong.

 

[Jerther]

I did some more tests yesterday. I couldn't find anything different between D and B modes while in ePedal mode. Regen is the same, acceleration is the same, braking is the same, the throttle pedal position at which regen starts is the same.

This is on my 2024 SL+. I recall this being the same on my previous 2018 SL.

Interesting thing, the motor rotates and consumes energy when coasting in N. The motor and the wheels are permanently coupled, so the motor has to rotate at the same speed to simulate a pseudo neutral situation. If the motor tries to rotate slower, regeneration will occur. That is because the LEAF motor uses permanent magnets, which has its pros and cons. IIRC the power used to rotate the motor at 100 km/h in neutral mode is not negligible, and of course the faster, the greater the power.

It'd be nice to have some kind of HUD with a global % efficiency. Just a crazy idea.

 

[Zero Emissions]

It also applies regen earlier in D mode. I find it much easier to coast or slow without regen or braking in e-Pedal B mode. As if the "coast window"is larger in B over D. I also find regen is less strong in B mode, which I prefer, since I can more easily coast to a light and when near and slowly apply regen. My efficiency is definitely better since switching to B instead of D. But some of the time I simply forget to double shift.

Hi there you say "I also find regen is less strong in B mode" Correct me if i'm wrong but isn't "B" mode all re-gen Why would it be less strong in B mode If its less strong why even have it on the vehicle? So would one be better off just keeping it in the "D" mode to get more re-gen? Enquiring minds want to know.

 

[BillAinCT]

I find B mode applies regen to a lesser degree in e-Pedal mode. I never drive with e-Pedal off, except when I had the car at the dealer to look at something and then ran a stop sign leaving the parking lot (not kidding). One way I gauge this is after 2 1/2 years in D mode I knew very well when to let off the pedal to stop at a light or stop sign. In B mode using that muscle memory, I have to apply the brakes to stop in time and I'm relearning the distance it takes to stop without my assisting.

 

[Zero Emissions]

Mine is a 2017 so I don't believe I have E-pedal and I find that the "B" modes in a very short distance like under 800 ft. can increase battery by 1% then another 800ft. increase another 1% That's been my experience anyway.

 

[JohnBike]

I have a 2020 S Plus I drive with the epedal in D when I come to a stop I take my foot off the brake and my car never moves, creeping or otherwise even if downhill. I just sits there until I press the accelerator. Does that mean there is something wrong with my car?

Nothing wrong. That’s the way ePedal is supposed to work.
BTW, if you’re using the brake, you’re not taking full advantage of ePedal. I often drive 20-30 miles without ever touching the brake pedal* except to start at first. Great way to reduce the habit of jackrabbit acceleration and hard braking.
*Except when some jerk cuts me off and triggers an emergency slam on the brakes.