Porsche says One-Pedal is not the most effecient

[B25Nut]

This is what I have felt all along:
The Porsche Taycan makes greater use of coasting, only using regenerative braking when the brake pedal is actually pressed. In a recent press release, the automaker explains the thinking behind that. "This is a more efficient way of driving," Martin Reichenecker, senior manager for chassis testing at Porsche Engineering, said in the release, "because it keeps the kinetic energy in the vehicle".

https://www.greencarreports.com/news/1138776_one-pedal-driving-in-evs-isn-t-efficient-says-porsche

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[Neil4Real]

It seems to be negligible one way or the other. I personally like how one pedal works and never needing to touch the brake. Once you get used to it, it’s amazing (in my opinion).

 

[kltye]

This is what I have felt all along:
The Porsche Taycan makes greater use of coasting, only using regenerative braking when the brake pedal is actually pressed. In a recent press release, the automaker explains the thinking behind that. "This is a more efficient way of driving," Martin Reichenecker, senior manager for chassis testing at Porsche Engineering, said in the release, "because it keeps the kinetic energy in the vehicle".

https://www.greencarreports.com/news/1138776_one-pedal-driving-in-evs-isn-t-efficient-says-porsche

You can't argue with physics - it's much more efficient to avoid any energy going in or out of the system, rather than constantly converting chemical energy into DC, then converting to AC, and then reverse that when regen'ing. Most people simply prefer the convenience of 1PD; it has nothing to do with efficiency.

Maybe it's because I'm a weak millennial snowflake, but I can't be bothered to feather the throttle to maintain any sort of speed. Driving with 1PD reminds me of a new driver who constantly switches between brakes and gas. But that's just me

 

[Kamuelaflyer]

much more efficient to avoid any energy going in or out of the system

Last time I drove to Kona I hit the top of the hill at 74% soc. I used 1pd to the bottom of the hill. I was at 82%. So turning 1pd would be even more efficient?

But that's just me

Yes, it’s your preference.

 

[kltye]

Last time I drove to Kona I hit the top of the hill at 74% soc. I used 1pd to the bottom of the hill. I was at 82%. So turning 1pd would be even more efficient?

Pretty sure it'd be the same efficiency if you pushed the brakes or used L.

 

[MG101]

Coasting is just coming to a stop very slowly. If that energy isn't going back to the battery it's being wasted.

 

[SpaceEVDriver]

It's true, but there's a massive caveat that needs to be included and was not mentioned in the article. Coasting is more efficient, but it's only really usable if you have the time and distance to coast. Driving in any kind of traffic usually negates that option. Even though it's more efficient to accelerate and decelerate slowly, we just don't have that luxury in most driving situations.

One of the things I miss about having a manual shift transmission is that I could choose when to coast and when to engine-brake. With the Mustang, I can either coast or motor-brake, but the drive selector is too poorly-designed to allow swapping whenever it makes sense to do so. I prefer the feeling of 1 PD simply because it feels more like engine-braking rather than coasting and I feel more in control.

 

[macchiaz-o]

The article in the OP seems to be rehashing information from this Porsche press release, though without attribution:

https://newsroom.porsche.com/en/202...ke-force-distribution-recuperation-30953.html

The source article, like the Green Car Reports one, seems to have errors that GCR then exacerbated.

Mainly, Porsche says in one sentence implies that hydraulic brakes are rarely needed and therefore can be made smaller. But then in another sentence they explain that hydraulic brakes are still crucial for emergency stops.

Anyway, the Taycan and the Mach-E both have blended braking it's just that the Taycan engineers weren't able to offer 1PD for some reason, so their newsroom gets to spin on what they do have.

I'm not trying to denigrate Porsche. Ford marketing does the same sort of spin, and I'd love to drive a Taycan instead of a Ford if somehow my $ costs were similar.

 

[Scooby24]

It's true, but there's a massive caveat that needs to be included and was not mentioned in the article. Coasting is more efficient, but it's only really usable if you have the time and distance to coast. Driving in any kind of traffic usually negates that option. Even though it's more efficient to accelerate and decelerate slowly, we just don't have that luxury in most driving situations.

One of the things I miss about having a manual shift transmission is that I could choose when to coast and when to engine-brake. With the Mustang, I can either coast or motor-brake, but the drive selector is too poorly-designed to allow swapping whenever it makes sense to do so. I prefer the feeling of 1 PD simply because it feels more like engine-braking rather than coasting and I feel more in control.

Agreed. 1PD is most efficient, in my experience, in city traffic or highway congestion. When driving back roads or highway driving where you can get up to speed and maintain it, you want to coast for most efficiency.

 

[HGxxx]

I think terrain plays a factor here and on a flat highway I don't think Regen or Regen makes a difference

 

[randomvoice]

After using 1 pedal driving, I can't go back to traditional driving even if it is 'more efficient'. I also have an ICE car and honestly, it is jarring going back. Yeah it might not be as 'engaging' but not having to worry about pressing the brakes is just amazing for daily driving. Overall, my next car that replaces my ICE vehicle will have 1 pedal driving as well!

 

[kltye]

Coasting is just coming to a stop very slowly. If that energy isn't going back to the battery it's being wasted.

It's only being wasted if you're using friction brakes without any regen. A car comes to a stop when it coasts because of drivetrain friction, aerodynamics, and friction between tires and the road - all of which still exist no matter how you brake. Regen simply harvests the energy from what would have been friction braking.

My argument (and Porsche's) is that you can overshoot your braking with 1PD (because it's difficult to feather the throttle), and therefore will have to hit the gas again to get going. In other words, it's the possibility of too much braking that's causing the loss in efficiency in 1PD. Now, how much less efficient is another question...

 

[macchiaz-o]

My argument (and Porsche's) is that you can overshoot your braking with 1PD (because it's difficult to feather the throttle), and therefore will have to hit the gas again to get going. In other words, it's the possibility of too much braking that's causing the loss in efficiency in 1PD. Now, how much less efficient is another question...

I can overshoot braking with a brake pedal or an accelerator pedal.

But if I use 1PD, I don't have to move my foot to a different pedal as often. With 1PD, when I over-brake or over-accelerate it is easier to correct and less likely to reoccur thanks to fewer foot initialization events.

 

[kltye]

I can overshoot braking with a brake pedal or an accelerator pedal.

But if I use 1PD, I don't have to move my foot to a different pedal as often. With 1PD, when I over-brake or over-accelerate it is easier to correct and less likely to reoccur thanks to fewer foot initialization events.

The lack of power display on the IPC (at least for those of us who can't Forscan their way into it) makes it difficult to see the "dead zone" of where the throttle is between "gas" and "brake". I don't think that zone is very large, so you're almost always either taking energy out of the batteries, or putting it back in - no in between.

 

[macchiaz-o]

The lack of power display on the IPC (at least for those of us who can't Forscan their way into it) makes it difficult to see the "dead zone" of where the throttle is between "gas" and "brake". I don't think that zone is very large, so you're almost always either taking energy out of the batteries, or putting it back in - no in between.

You may be right. Though I hope the vehicle notices that I'm trying to maintain a certain speed and it chooses to operate reasonably efficiently. It's not like I'm constantly moving my foot up and down... I'm being as gradual as is reasonable for the situation.

Speaking of which, I just realized Porsche's press article conveniently excludes mention of cruise control, in which 1PD vs 2PD is rendered moot.

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