How long to get that predicted 270 mile range?

[Frankie]

How is REGENERATIVE braking not good for efficiency?

Where did I say that?

What I said was treating the "gas"/regen like an on/off switch isn't good for efficiency, and that is literally a fact, because coasting is more efficient than regen. If you want to drive that way great for you, it's good that you've got regen so you're not wasting all that energy to heat, but don't pretend that it's the most efficient way to drive.

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[Frankie]

Got it. This is one of those "on a closed course that's been laser leveled under ideal conditions" things.

No. Coasting is more efficient than regen, period. You don't need to be on a closed course that's been laser leveled under ideal conditions to coast.

 

[Trede]

No. Coasting is more efficient than regen, period. You don't need to be on a closed course that's been laser leveled under ideal conditions to coast.

Coasting (using 0 energy to go from 20-0 over howevermanyfeetittakes) being more efficient than regen (gaining any amount of energy to go from 20-0 over ittakeslessfeettodothis) doesn't make logical sense to me, but I'm not going to argue. I'll just be happy with my mi/kwh staying north of 5 since the weather is getting nice here.

 

[Frankie]

Coasting (using 0 energy to go from 20-0 over howevermanyfeetittakes) being more efficient than regen (gaining any amount of energy to go from 20-0 over ittakeslessfeettodothis) doesn't make logical sense to me, but I'm not going to argue. I'll just be happy with my mi/kwh staying north of 5 since the weather is getting nice here.

There's not really anything to argue about, it's not logic, it's physics.

Here's a fairly good explanation if you're having trouble understanding it.

It all comes down to conversion losses. Every time you convert energy to another type of energy, some gets wasted in the process. When you take the chemical energy in your battery and convert it into electrical energy, some of that energy gets lost as heat. Hopefully your EV has liquid cooling to get rid of that heat. After that, the motor converts electricity into mechanical energy, and a little more energy gets lost to heat. Then, your car uses the drivetrain, wheels, and tires to convert that mechanical energy into kinetic energy (your car moving). Once again, some of that energy gets lost to heat. It all adds up.

Regenerative braking does all this in reverse. The car’s kinetic energy becomes mechanical energy, turning the motor/generator. The motor/generator turns the mechanical energy into electricity. The electricity then goes back into your battery pack. At each of those steps, some energy gets lost to heat.

In the end, only about 60% of the energy that left the battery pack actually survives the round trip.

Coasting works because your car is always fighting resistance to keep moving. Your car has to push itself through the air. There’s rolling resistance between the tires and the road. The wheel bearings are also constantly trying to slow the car down a bit. All that adds up, and will slowly bring your car to a stop if you quit adding energy from the motor. It turns out that this is the most efficient way to bring the car to a stop (when possible) because you let off on the accelerator pedal sooner. Instead of wasting energy to keep going and then using brakes, you keep the energy in your battery pack more.

By skipping the conversion losses, you maximize your range.

https://cleantechnica.com/2020/12/15/regenerative-braking-vs-coasting-volkswagen-id-4-gets-it-right/

 

[Trede]

Aha, thank you for reiterating that explanation (I vaguely remember reading that/similar, and for some reason didn't click until now). My last EV was a Chevy Bolt, which did have a real-time display of kw usage/regen, so of course I played the 1PD "get the best mi/kwh" game (Averaged around 4.1 over the course of 4 or 5 months...before it got cold). It did involve a lot of keeping it at or as close to 0 as possible, timing the 1pd for stopping distance...at this point I'm probably just subconsciously coasting-or-close-to-it (holding the pedal at just the right pressure) if I'm not accelerating or going down a steep hill or...I don't use cruise control much, but I enjoy the 1PD "game" of keeping it at exactly 25/47/65mph, instant accelerations, and the super gradual "no-lurch" stops.

 

[Brussam]

It keeps getting better. Today I pulled out of the garage with 354 miles on the range meter.. Regulated garage temperature helps a lot.

 

[BMT1071]

Aha, thank you for reiterating that explanation (I vaguely remember reading that/similar, and for some reason didn't click until now). My last EV was a Chevy Bolt, which did have a real-time display of kw usage/regen, so of course I played the 1PD "get the best mi/kwh" game (Averaged around 4.1 over the course of 4 or 5 months...before it got cold). It did involve a lot of keeping it at or as close to 0 as possible, timing the 1pd for stopping distance...at this point I'm probably just subconsciously coasting-or-close-to-it (holding the pedal at just the right pressure) if I'm not accelerating or going down a steep hill or...I don't use cruise control much, but I enjoy the 1PD "game" of keeping it at exactly 25/47/65mph, instant accelerations, and the super gradual "no-lurch" stops.

I think your MME is the only one I've seen out in the wild. Mid-April at Jimmy John's in Kent, around lunch time. ?

 

[Trede]

I think your MME is the only one I've seen out in the wild. Mid-April at Jimmy John's in Kent, around lunch time. ?

Yeah, that tracks. I live JUST outside the delivery radii of two Jimmy John'ses. Just another excuse to drive the mustang, so I'm not complaining.

 

[Petter]

use the braking coach to learn how to extract the most regen

I have only had my MME FE since 5/20 and have quite a few things to learn;-) One of the things is how the break coach actually works. I've tried the manual but am still at a loss. May I ask you to explain?

 

[dbsb3233]

Revisiting the title question... I'm now 3000 miles in to my FE (270 EPA), and the GOM is still consistently predicting 220-230 miles of range. Even though the vehicle lifetime (using Trip2 for that) is showing 3.0 MPK. That calculates to nearly EPA, but my GOM consistently shows 15% below my actual range.

But some others are reporting great GOM numbers. It's so inconsistent, almost like there's totally different software being used on some vs others. (I've only noticed one OTA, but hard to know what the car was delivered with in Feb.)

 

[dbsb3233]

I have only had my MME FE since 5/20 and have quite a few things to learn;-) One of the things is how the break coach actually works. I've tried the manual but am still at a loss. May I ask you to explain?

Brake Coach only comes on in one or two drive modes. In fact it may only be the middle one (Engaged in the US). With 1PD off.

It pops up on the left side of the driver screen for 2-3 seconds after using the brake pedal and slowing to a near stop.

 

[JoeDimwit]

I have only had my MME FE since 5/20 and have quite a few things to learn;-) One of the things is how the break coach actually works. I've tried the manual but am still at a loss. May I ask you to explain?

You have to enable it in the settings, then it only works in Engage mode.. when you come to a stop, it should put a circle graph on the left side of the gauge cluster that tells you how much available energy you recovered. Higher percentages mean the friction brakes are being used less, and that’s what you want.

 

[dbsb3233]

You have to enable it in the settings, then it only works in Engage mode.. when you come to a stop, it should put a circle graph on the left side of the gauge cluster that tells you how much available energy you recovered. Higher percentages mean the friction brakes are being used less, and that’s what you want.

It's so bizarre that it doesn't work in Whisper mode. Makes no sense. Unless Whisper mode doesn't use regen via the brake pedal at all, but I don't think that's the case.

 

[smp]

It's so bizarre that it doesn't work in Whisper mode. Makes no sense. Unless Whisper mode doesn't use regen via the brake pedal at all, but I don't think that's the case.

I have read somewhere that Whisper mode does only coasting and does not do regen.
Unfortunately, I cannot find that writing to offer a link, so I cannot verify, but it sounds plausible to me.
The consensus here is that there is regen in all 3 modes, and OPD can be layered on top of each of them.

smp

 

[dbsb3233]

I have read somewhere that Whisper mode does only coasting and does not do regen.
Unfortunately, I cannot find that writing to offer a link, so I cannot verify, but it sounds plausible to me.
The consensus here is that there is regen in all 3 modes, and OPD can be layered on top of each of them.

smp

Coasting when not pressing either pedal, yes. But I assume using the brake pedal still uses regen for the vast majority of the slowing (except for the last few MPH, and more severe slowing).

If the brake pedal doesn't use any regen in Whisper, that would seem to be a pretty significant hit to range.

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