One pedal drive (vs) Brake regen

Ming

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This is the answer! Drive mode doesn't reduce efficiency, the way you drive does!
That's correct. Braking gently with 2PD mode would reclaim the kinetic energy back to battery, just like 1PD does.

Although that's not OP's proposed usage. OP wants to coast without braking until the end then hard brake to stop, thus convert most energy to heat.
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Space Ghost GT

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I got used to 1-p driving fairly fast; the Break Coach feeback says I'm getting 95% or better.
The trick is to accellerate slowly and back off the accellerator slowly; near stop, the amount of 'breaking' increases--very good. I rarely use the brakes. This also means brake pad life is extended.

The other question I had was: If you use regenerative breaking, do the brake lights go on?
The answer is yes: you can see the red glow in the rear-facing camera when back off the accellerator when backing up.
I get 100% with 2 pd driving so another victory for 2pd
 
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kkgg

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That's correct. Braking gently with 2PD mode would reclaim the kinetic energy back to battery, just like 1PD does.

Although that's not OP's proposed usage. OP wants to coast without braking until the end then hard brake to stop, thus convert most energy to heat.
No, my case is to coast with out breaking then smooth regen braking
 

ctenidae

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You are comparing apples to oranges here. If you drag the brakes with regen you will not travel as far as if you didn’t. For your scenario to be true regen would have to be 100% efficient and it’s more like 60-70%. So your using more energy to go a shorter distance dragging the brake constantly
Your scenario is ridiculous. Of course you would go further if you're not applying any stopping force. But when you coast you lose 100% of the energy you input to get up to speed. You bleed kinetic energy, and gain no potential energy. When you regen, you convert kinetic energy into potential energy. Reclaiming some energy is more efficient than losing all your energy. You can not coast, in any vehicle, in any way that changes that formula. Distance traveled is not the only factor- potential energy is a huge part of it.

Put another way, consider the dynamics of delta-v (changes in velocity, dV). Two cars use the same amount of energy (same dV) to go from 0 to 100 mph. One coasts to a stop - no dV applied (all energy input is lost to friction). The other maintains its speed longer, adding some dV to overcome losses from friction. It then uses regenerative braking to come to a stop in the same place as the coasting car. It has used slightly more dV than the coasting car to get to its braking point, but then it regains much of the original dV input as it regens. If the two vehicles are the same from a friction perspective, the coasting car has 0 dV when it stops, while the regen car has positive dV. That means you could still go some distance further in the braking car, while the coasting car has no dV left.

Granted, over a very long distance you could use more dV to maintain speed than you gain during braking. However, you can't coast that far and you will have to add dV to get back up to speed, 100% of which will be lost when you finally stop. Assuming the two vehicles are identical in the amount of dV it takes to maintain or regain that speed, you will still end up with 0dV in the coasting car, and a positive dV in the braking car, meaning you could still go further in the braking car than you can in the coasting car.
 


Space Ghost GT

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That's because you're using regenerative braking.
That’s what the 1pd fanatics can’t understand is that yes you do regen with 2pd in a more efficient manner than constantly dragging the brakes and burning up that kinetic energy at a 60% recovery rate vs 100% retention minus the bearing drag by coasting in whisper in 2pd.
 

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That’s what the 1pd fanatics can’t understand is that yes you do regen with 2pd in a more efficient manner than constantly dragging the brakes and burning up that kinetic energy at a 60% recovery rate vs 100% retention minus the bearing drag by coasting in whisper in 2pd.
Who is constantly dragging the brake, though? I'm not. Can you not maintain a speed on the highway?
 

Space Ghost GT

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Who is constantly dragging the brake, though? I'm not. Can you not maintain a speed on the highway?
There is one pixel of difference between throttle and regen with 1pd. So as polstar says it’s like driving with a boat anchor on the highway with 1pd. You are spending energy and losing energy through 1pd by constantly dragging the brake with 1pd by futility trying to maintain a cruising speed.
 

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Who is constantly dragging the brake, though? I'm not. Can you not maintain a speed on the highway?
Also it’s a reason why Teslas have such poor highway range as you are locked into an inefficient marketing hype drive mode. Any why Tesla’s are always trundling along because 1pd.
 

ctenidae

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There is one pixel of difference between throttle and regen with 1pd. So as polstar says it’s like driving with a boat anchor on the highway with 1pd. You are spending energy and losing energy through 1pd by constantly dragging the brake with 1pd by futility trying to maintain a cruising speed.
But you are constantly losing energy with no regen by coasting. At worst, 6 of one and half dozen of the other.

If you think you are more efficient physically using the brake pedal in 2PD to regenerate, then that's fine. You do you, as you say. But stop with the "coasting is more efficient" dogma, because, well, physics. Instead, say "I am better than the computer at managing my regen," because that's really what you're doing.

Also, when I Google Polestar boat anchor I just get pictures of anchors. Can you link to where you saw that? I'm interested in seeing how they qualify the statement.
 

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That’s what the 1pd fanatics can’t understand is that yes you do regen with 2pd in a more efficient manner than constantly dragging the brakes and burning up that kinetic energy at a 60% recovery rate vs 100% retention minus the bearing drag by coasting in whisper in 2pd.
Next time you go down a long hill put your car in N and gently brake. There is no regen in N and it cleans off your rotors. Check your regen - 100% : The meter does not actual measure regen - just a simulation based on how smoothly you apply the brakes (or so it appears to me)
 

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But you are constantly losing energy with no regen by coasting. At worst, 6 of one and half dozen of the other.

If you think you are more efficient physically using the brake pedal in 2PD to regenerate, then that's fine. You do you, as you say. But stop with the "coasting is more efficient" dogma, because, well, physics. Instead, say "I am better than the computer at managing my regen," because that's really what you're doing.

Also, when I Google Polestar boat anchor I just get pictures of anchors. Can you link to where you saw that? I'm interested in seeing how they qualify the statement.
From road and track - https://www.roadandtrack.com/car-cu...rily-the-most-efficient-way-of-driving-an-ev/

A rep from Polestar, told me that like-for-like, there is theoretically no difference in its cars, which offer a one-pedal mode but also use a blended brake pedal. He also added that one-pedal driving is actually less efficient on the highway, likening it to dragging a boat anchor around, making it extremely difficult to maintain a constant speed. Obviously, this isn’t an issue if you just turn on cruise control and just forget about it as the car does all the work, but not everyone uses cruise control, especially on busy highways.
 

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Is that true? I have used 2P and coasted (while in drive) and it certainly feels like there is very little regen slowing the car down. I have been amazed (coming out of 1P) how far it will coast. Never tried it in neutral,
It’s true in the sense that all three drive modes have a degree of regen built in from minimal in whisper to the most robust in unbridled, as was pointed out much earlier in this thread.

Im personally not going to weigh in on this. I drive 1pd exclusively because I like it, I expect that other mme owners will drive their cars the way they like as well.

I will say that this discussion is far better than most on this forum and better than the other distant past discussion in this topic,
 

ctenidae

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The bulk of the article says 1PD and 2PD are effectively the same and it's up to you how you like to drive.

Porsche does lift-off regen (even though not true 1PD) that simulates engine braking. Meaning, it doesn't coast, either, because that's wasteful. Polestar says there's very little difference in reality between 1PD and 2PD (boat anchor comment notwithstanding). BMW actively manages the amount of liftoff regen for conditions, never, apparently, "coasting."

The article is interesting in its one conclusory statement, though: "If there's any conclusion to be drawn here, it's perhaps that you don't need to worry so much about one-pedal driving... if you don't like it, chances are you're not leaving a lot, if any, extra range on the table." If you don't use it, you're leaving some range on the table. That is their conclusion. Ergo, that article says 1PD is more efficient. Maybe not a lot, maybe none. It pointedly does not say that if you use 1PD you're leaving some range on the table, though.

Interestingly, the article opens with what I think is the #1 issue people have with 1PD - they don't know how to drive with it. From the article : "You lift off the accelerator pedal, and wham! You nearly come to a complete stop." That's known in the common parlance as "doing it wrong."
 

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regenerative braking is 'pretty darn efficient', just losing a few percent due to motor/inverter efficiency.
Was reading this thread and noticed this on the first page. This is not true. CONSUMING power is very efficient but regen is not. It is between 60-80% efficient. Typically not over 70% efficient. The other is lost as heat in the conversion process from AC to DC to charge the battery pack.
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